summaryrefslogtreecommitdiffstats
path: root/services/java/com/android/server/am/ActivityStackSupervisor.java
blob: 7650a65324b7d5238820da4ef64bda55646f717c (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
1824
1825
1826
1827
1828
1829
1830
1831
1832
1833
1834
1835
1836
1837
1838
1839
1840
1841
1842
1843
1844
1845
1846
1847
1848
1849
1850
1851
1852
1853
1854
1855
1856
1857
1858
1859
1860
1861
1862
1863
1864
1865
1866
1867
1868
1869
1870
1871
1872
1873
1874
1875
1876
1877
1878
1879
1880
1881
1882
1883
1884
1885
1886
1887
1888
1889
1890
1891
1892
1893
1894
1895
1896
1897
1898
1899
1900
1901
1902
1903
1904
1905
1906
1907
1908
1909
1910
1911
1912
1913
1914
1915
1916
1917
1918
1919
1920
1921
1922
1923
1924
1925
1926
1927
1928
1929
1930
1931
1932
1933
1934
1935
1936
1937
1938
1939
1940
1941
1942
1943
1944
1945
1946
1947
1948
1949
1950
1951
1952
1953
1954
1955
1956
1957
1958
1959
1960
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
2028
2029
2030
2031
2032
2033
2034
2035
2036
2037
2038
2039
2040
2041
2042
2043
2044
2045
2046
2047
2048
2049
2050
2051
2052
2053
2054
2055
2056
2057
2058
2059
2060
2061
2062
2063
2064
2065
2066
2067
2068
2069
2070
2071
2072
2073
2074
2075
2076
2077
2078
2079
2080
2081
2082
2083
2084
2085
2086
2087
2088
2089
2090
2091
2092
2093
2094
2095
2096
2097
2098
2099
2100
2101
2102
2103
2104
2105
2106
2107
2108
2109
2110
2111
2112
2113
2114
2115
2116
2117
2118
2119
2120
2121
2122
2123
2124
2125
2126
2127
2128
2129
2130
2131
2132
2133
2134
2135
2136
2137
2138
2139
2140
2141
2142
2143
2144
2145
2146
2147
2148
2149
2150
2151
2152
2153
2154
2155
2156
2157
2158
2159
2160
2161
2162
2163
2164
2165
2166
2167
2168
2169
2170
2171
2172
2173
2174
2175
2176
2177
2178
2179
2180
2181
2182
2183
2184
2185
2186
2187
2188
2189
2190
2191
2192
2193
2194
2195
2196
2197
2198
2199
2200
2201
2202
2203
2204
2205
2206
2207
2208
2209
2210
2211
2212
2213
2214
2215
2216
2217
2218
2219
2220
2221
2222
2223
2224
2225
2226
2227
2228
2229
2230
2231
2232
2233
2234
2235
2236
2237
2238
2239
2240
2241
2242
2243
2244
2245
2246
2247
2248
2249
2250
2251
2252
2253
2254
2255
2256
2257
2258
2259
2260
2261
2262
2263
2264
2265
2266
2267
2268
2269
2270
2271
2272
2273
2274
2275
2276
2277
2278
2279
2280
2281
2282
2283
2284
2285
2286
2287
2288
2289
2290
2291
2292
2293
2294
2295
2296
2297
2298
2299
2300
2301
2302
2303
2304
2305
2306
2307
2308
2309
2310
2311
2312
2313
2314
2315
2316
2317
2318
2319
2320
2321
2322
2323
2324
2325
2326
2327
2328
2329
2330
2331
2332
2333
2334
2335
2336
2337
2338
2339
2340
2341
2342
2343
2344
2345
2346
2347
2348
2349
2350
2351
2352
2353
2354
2355
2356
2357
2358
2359
2360
2361
2362
2363
2364
2365
2366
2367
2368
2369
2370
2371
2372
2373
2374
2375
2376
2377
2378
2379
2380
2381
2382
2383
2384
2385
2386
2387
2388
2389
2390
2391
2392
2393
2394
2395
2396
2397
2398
2399
2400
2401
2402
2403
2404
2405
2406
2407
2408
2409
2410
2411
2412
2413
2414
2415
2416
2417
2418
2419
2420
2421
2422
2423
2424
2425
2426
2427
2428
2429
2430
2431
2432
2433
2434
2435
2436
2437
2438
2439
2440
2441
2442
2443
2444
2445
2446
2447
2448
2449
2450
2451
2452
2453
2454
2455
2456
2457
2458
2459
2460
2461
2462
2463
2464
2465
2466
2467
2468
2469
2470
2471
2472
2473
2474
2475
2476
2477
2478
2479
2480
2481
2482
2483
2484
2485
2486
2487
2488
2489
2490
2491
2492
2493
2494
2495
2496
2497
2498
2499
2500
2501
2502
2503
2504
2505
2506
2507
2508
2509
2510
2511
2512
2513
2514
2515
2516
2517
2518
2519
2520
2521
2522
2523
2524
2525
2526
2527
2528
2529
2530
2531
2532
2533
2534
2535
2536
2537
2538
2539
2540
2541
2542
2543
2544
2545
2546
2547
2548
2549
2550
2551
2552
2553
2554
2555
2556
2557
2558
2559
2560
2561
2562
2563
2564
2565
2566
2567
2568
2569
2570
2571
2572
2573
2574
2575
2576
2577
2578
2579
2580
2581
2582
2583
2584
2585
2586
2587
2588
2589
2590
2591
2592
2593
2594
2595
2596
2597
2598
2599
2600
2601
2602
2603
2604
2605
2606
2607
2608
2609
2610
2611
2612
2613
2614
2615
2616
2617
2618
2619
2620
2621
2622
2623
2624
2625
2626
2627
2628
2629
2630
2631
2632
2633
2634
2635
2636
2637
2638
2639
2640
2641
2642
/*
 * Copyright (C) 2013 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.android.server.am;

import static android.Manifest.permission.START_ANY_ACTIVITY;
import static android.content.Intent.FLAG_ACTIVITY_NEW_TASK;
import static android.content.Intent.FLAG_ACTIVITY_TASK_ON_HOME;
import static android.content.pm.PackageManager.PERMISSION_GRANTED;
import static com.android.server.am.ActivityManagerService.localLOGV;
import static com.android.server.am.ActivityManagerService.DEBUG_CONFIGURATION;
import static com.android.server.am.ActivityManagerService.DEBUG_FOCUS;
import static com.android.server.am.ActivityManagerService.DEBUG_PAUSE;
import static com.android.server.am.ActivityManagerService.DEBUG_RESULTS;
import static com.android.server.am.ActivityManagerService.DEBUG_STACK;
import static com.android.server.am.ActivityManagerService.DEBUG_SWITCH;
import static com.android.server.am.ActivityManagerService.DEBUG_TASKS;
import static com.android.server.am.ActivityManagerService.DEBUG_USER_LEAVING;
import static com.android.server.am.ActivityManagerService.FIRST_SUPERVISOR_STACK_MSG;
import static com.android.server.am.ActivityManagerService.TAG;

import android.app.Activity;
import android.app.ActivityManager;
import android.app.ActivityOptions;
import android.app.AppGlobals;
import android.app.IActivityManager;
import android.app.IApplicationThread;
import android.app.IThumbnailReceiver;
import android.app.PendingIntent;
import android.app.ActivityManager.RunningTaskInfo;
import android.app.IActivityManager.WaitResult;
import android.app.ResultInfo;
import android.content.ComponentName;
import android.content.Context;
import android.content.IIntentSender;
import android.content.Intent;
import android.content.IntentSender;
import android.content.pm.ActivityInfo;
import android.content.pm.ApplicationInfo;
import android.content.pm.PackageManager;
import android.content.pm.ResolveInfo;
import android.content.res.Configuration;
import android.os.Binder;
import android.os.Bundle;
import android.os.Debug;
import android.os.Handler;
import android.os.IBinder;
import android.os.Looper;
import android.os.Message;
import android.os.ParcelFileDescriptor;
import android.os.PowerManager;
import android.os.Process;
import android.os.RemoteException;
import android.os.SystemClock;
import android.os.UserHandle;
import android.util.EventLog;
import android.util.Slog;
import android.util.SparseIntArray;

import com.android.internal.app.HeavyWeightSwitcherActivity;
import com.android.internal.os.TransferPipe;
import com.android.server.am.ActivityManagerService.PendingActivityLaunch;
import com.android.server.am.ActivityStack.ActivityState;
import com.android.server.wm.StackBox;
import com.android.server.wm.WindowManagerService;

import java.io.FileDescriptor;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.ArrayList;
import java.util.List;

public final class ActivityStackSupervisor {
    static final boolean DEBUG = ActivityManagerService.DEBUG || false;
    static final boolean DEBUG_ADD_REMOVE = DEBUG || false;
    static final boolean DEBUG_APP = DEBUG || false;
    static final boolean DEBUG_SAVED_STATE = DEBUG || false;
    static final boolean DEBUG_STATES = DEBUG || false;
    static final boolean DEBUG_IDLE = DEBUG || false;

    public static final int HOME_STACK_ID = 0;

    /** How long we wait until giving up on the last activity telling us it is idle. */
    static final int IDLE_TIMEOUT = 10*1000;

    /** How long we can hold the sleep wake lock before giving up. */
    static final int SLEEP_TIMEOUT = 5*1000;

    // How long we can hold the launch wake lock before giving up.
    static final int LAUNCH_TIMEOUT = 10*1000;

    static final int IDLE_TIMEOUT_MSG = FIRST_SUPERVISOR_STACK_MSG;
    static final int IDLE_NOW_MSG = FIRST_SUPERVISOR_STACK_MSG + 1;
    static final int RESUME_TOP_ACTIVITY_MSG = FIRST_SUPERVISOR_STACK_MSG + 2;
    static final int SLEEP_TIMEOUT_MSG = FIRST_SUPERVISOR_STACK_MSG + 3;
    static final int LAUNCH_TIMEOUT_MSG = FIRST_SUPERVISOR_STACK_MSG + 4;

    // For debugging to make sure the caller when acquiring/releasing our
    // wake lock is the system process.
    static final boolean VALIDATE_WAKE_LOCK_CALLER = false;

    final ActivityManagerService mService;
    final Context mContext;
    final Looper mLooper;

    final ActivityStackSupervisorHandler mHandler;

    /** Short cut */
    WindowManagerService mWindowManager;

    /** Dismiss the keyguard after the next activity is displayed? */
    boolean mDismissKeyguardOnNextActivity = false;

    /** Identifier counter for all ActivityStacks */
    private int mLastStackId = HOME_STACK_ID;

    /** Task identifier that activities are currently being started in.  Incremented each time a
     * new task is created. */
    private int mCurTaskId = 0;

    /** The current user */
    private int mCurrentUser;

    /** The stack containing the launcher app */
    private ActivityStack mHomeStack;

    /** The non-home stack currently receiving input or launching the next activity. If home is
     * in front then mHomeStack overrides mFocusedStack.
     * DO NOT ACCESS DIRECTLY - It may be null, use getFocusedStack() */
    private ActivityStack mFocusedStack;

    /** All the non-launcher stacks */
    private ArrayList<ActivityStack> mStacks = new ArrayList<ActivityStack>();

    private static final int STACK_STATE_HOME_IN_FRONT = 0;
    private static final int STACK_STATE_HOME_TO_BACK = 1;
    private static final int STACK_STATE_HOME_IN_BACK = 2;
    private static final int STACK_STATE_HOME_TO_FRONT = 3;
    private int mStackState = STACK_STATE_HOME_IN_FRONT;

    /** List of activities that are waiting for a new activity to become visible before completing
     * whatever operation they are supposed to do. */
    final ArrayList<ActivityRecord> mWaitingVisibleActivities = new ArrayList<ActivityRecord>();

    /** List of processes waiting to find out about the next visible activity. */
    final ArrayList<IActivityManager.WaitResult> mWaitingActivityVisible =
            new ArrayList<IActivityManager.WaitResult>();

    /** List of processes waiting to find out about the next launched activity. */
    final ArrayList<IActivityManager.WaitResult> mWaitingActivityLaunched =
            new ArrayList<IActivityManager.WaitResult>();

    /** List of activities that are ready to be stopped, but waiting for the next activity to
     * settle down before doing so. */
    final ArrayList<ActivityRecord> mStoppingActivities = new ArrayList<ActivityRecord>();

    /** List of activities that are ready to be finished, but waiting for the previous activity to
     * settle down before doing so.  It contains ActivityRecord objects. */
    final ArrayList<ActivityRecord> mFinishingActivities = new ArrayList<ActivityRecord>();

    /** List of activities that are in the process of going to sleep. */
    final ArrayList<ActivityRecord> mGoingToSleepActivities = new ArrayList<ActivityRecord>();

    /** List of ActivityRecord objects that have been finished and must still report back to a
     * pending thumbnail receiver. */
    final ArrayList<ActivityRecord> mCancelledThumbnails = new ArrayList<ActivityRecord>();

    /** Used on user changes */
    final ArrayList<UserStartedState> mStartingUsers = new ArrayList<UserStartedState>();

    /** Set to indicate whether to issue an onUserLeaving callback when a newly launched activity
     * is being brought in front of us. */
    boolean mUserLeaving = false;

    /** Set when we have taken too long waiting to go to sleep. */
    boolean mSleepTimeout = false;

    /**
     * We don't want to allow the device to go to sleep while in the process
     * of launching an activity.  This is primarily to allow alarm intent
     * receivers to launch an activity and get that to run before the device
     * goes back to sleep.
     */
    final PowerManager.WakeLock mLaunchingActivity;

    /**
     * Set when the system is going to sleep, until we have
     * successfully paused the current activity and released our wake lock.
     * At that point the system is allowed to actually sleep.
     */
    final PowerManager.WakeLock mGoingToSleep;

    /** Stack id of the front stack when user switched, indexed by userId. */
    SparseIntArray mUserStackInFront = new SparseIntArray(2);

    public ActivityStackSupervisor(ActivityManagerService service, Context context,
            Looper looper) {
        mService = service;
        mContext = context;
        mLooper = looper;
        PowerManager pm = (PowerManager)context.getSystemService(Context.POWER_SERVICE);
        mGoingToSleep = pm.newWakeLock(PowerManager.PARTIAL_WAKE_LOCK, "ActivityManager-Sleep");
        mHandler = new ActivityStackSupervisorHandler(looper);
        if (VALIDATE_WAKE_LOCK_CALLER && Binder.getCallingUid() != Process.myUid()) {
            throw new IllegalStateException("Calling must be system uid");
        }
        mLaunchingActivity =
                pm.newWakeLock(PowerManager.PARTIAL_WAKE_LOCK, "ActivityManager-Launch");
        mLaunchingActivity.setReferenceCounted(false);
    }

    void setWindowManager(WindowManagerService wm) {
        mWindowManager = wm;
        mHomeStack = new ActivityStack(mService, mContext, mLooper, HOME_STACK_ID);
        mStacks.add(mHomeStack);
    }

    void dismissKeyguard() {
        if (ActivityManagerService.DEBUG_LOCKSCREEN) mService.logLockScreen("");
        if (mDismissKeyguardOnNextActivity) {
            mDismissKeyguardOnNextActivity = false;
            mWindowManager.dismissKeyguard();
        }
    }

    ActivityStack getFocusedStack() {
        if (mFocusedStack == null) {
            return mHomeStack;
        }
        switch (mStackState) {
            case STACK_STATE_HOME_IN_FRONT:
            case STACK_STATE_HOME_TO_FRONT:
                return mHomeStack;
            case STACK_STATE_HOME_IN_BACK:
            case STACK_STATE_HOME_TO_BACK:
            default:
                return mFocusedStack;
        }
    }

    ActivityStack getLastStack() {
        switch (mStackState) {
            case STACK_STATE_HOME_IN_FRONT:
            case STACK_STATE_HOME_TO_BACK:
                return mHomeStack;
            case STACK_STATE_HOME_TO_FRONT:
            case STACK_STATE_HOME_IN_BACK:
            default:
                return mFocusedStack;
        }
    }

    boolean isFrontStack(ActivityStack stack) {
        return !(stack.isHomeStack() ^ getFocusedStack().isHomeStack());
    }

    void moveHomeStack(boolean toFront) {
        final boolean homeInFront = isFrontStack(mHomeStack);
        if (homeInFront ^ toFront) {
            if (DEBUG_STACK) Slog.d(TAG, "moveHomeTask: mStackState old=" +
                    stackStateToString(mStackState) + " new=" + stackStateToString(homeInFront ?
                    STACK_STATE_HOME_TO_BACK : STACK_STATE_HOME_TO_FRONT));
            mStackState = homeInFront ? STACK_STATE_HOME_TO_BACK : STACK_STATE_HOME_TO_FRONT;
        }
    }

    void moveHomeToTop() {
        moveHomeStack(true);
        mHomeStack.moveHomeTaskToTop();
    }

    boolean resumeHomeActivity(ActivityRecord prev) {
        moveHomeToTop();
        if (prev != null) {
            prev.task.mOnTopOfHome = false;
        }
        ActivityRecord r = mHomeStack.topRunningActivityLocked(null);
        if (r != null && r.isHomeActivity()) {
            mService.setFocusedActivityLocked(r);
            return resumeTopActivitiesLocked(mHomeStack, prev, null);
        }
        return mService.startHomeActivityLocked(mCurrentUser);
    }

    void setDismissKeyguard(boolean dismiss) {
        if (ActivityManagerService.DEBUG_LOCKSCREEN) mService.logLockScreen(" dismiss=" + dismiss);
        mDismissKeyguardOnNextActivity = dismiss;
    }

    TaskRecord anyTaskForIdLocked(int id) {
        for (int stackNdx = mStacks.size() - 1; stackNdx >= 0; --stackNdx) {
            ActivityStack stack = mStacks.get(stackNdx);
            TaskRecord task = stack.taskForIdLocked(id);
            if (task != null) {
                return task;
            }
        }
        return null;
    }

    ActivityRecord isInAnyStackLocked(IBinder token) {
        for (int stackNdx = mStacks.size() - 1; stackNdx >= 0; --stackNdx) {
            final ActivityRecord r = mStacks.get(stackNdx).isInStackLocked(token);
            if (r != null) {
                return r;
            }
        }
        return null;
    }

    int getNextTaskId() {
        do {
            mCurTaskId++;
            if (mCurTaskId <= 0) {
                mCurTaskId = 1;
            }
        } while (anyTaskForIdLocked(mCurTaskId) != null);
        return mCurTaskId;
    }

    void removeTask(TaskRecord task) {
        mWindowManager.removeTask(task.taskId);
        final ActivityStack stack = task.stack;
        final ActivityRecord r = stack.mResumedActivity;
        if (r != null && r.task == task) {
            stack.mResumedActivity = null;
        }
        if (stack.removeTask(task) && !stack.isHomeStack()) {
            if (DEBUG_STACK) Slog.i(TAG, "removeTask: removing stack " + stack);
            mStacks.remove(stack);
            final int stackId = stack.mStackId;
            final int nextStackId = mWindowManager.removeStack(stackId);
            // TODO: Perhaps we need to let the ActivityManager determine the next focus...
            if (mFocusedStack == null || mFocusedStack.mStackId == stackId) {
                // If this is the last app stack, set mFocusedStack to null.
                mFocusedStack = nextStackId == HOME_STACK_ID ? null : getStack(nextStackId);
            }
        }
    }

    ActivityRecord resumedAppLocked() {
        ActivityStack stack = getFocusedStack();
        if (stack == null) {
            return null;
        }
        ActivityRecord resumedActivity = stack.mResumedActivity;
        if (resumedActivity == null || resumedActivity.app == null) {
            resumedActivity = stack.mPausingActivity;
            if (resumedActivity == null || resumedActivity.app == null) {
                resumedActivity = stack.topRunningActivityLocked(null);
            }
        }
        return resumedActivity;
    }

    boolean attachApplicationLocked(ProcessRecord app, boolean headless) throws Exception {
        boolean didSomething = false;
        final String processName = app.processName;
        for (int stackNdx = mStacks.size() - 1; stackNdx >= 0; --stackNdx) {
            final ActivityStack stack = mStacks.get(stackNdx);
            if (!isFrontStack(stack)) {
                continue;
            }
            ActivityRecord hr = stack.topRunningActivityLocked(null);
            if (hr != null) {
                if (hr.app == null && app.uid == hr.info.applicationInfo.uid
                        && processName.equals(hr.processName)) {
                    try {
                        if (headless) {
                            Slog.e(TAG, "Starting activities not supported on headless device: "
                                    + hr);
                        } else if (realStartActivityLocked(hr, app, true, true)) {
                            didSomething = true;
                        }
                    } catch (Exception e) {
                        Slog.w(TAG, "Exception in new application when starting activity "
                              + hr.intent.getComponent().flattenToShortString(), e);
                        throw e;
                    }
                }
            }
        }
        if (!didSomething) {
            ensureActivitiesVisibleLocked(null, 0);
        }
        return didSomething;
    }

    boolean allResumedActivitiesIdle() {
        for (int stackNdx = mStacks.size() - 1; stackNdx >= 0; --stackNdx) {
            final ActivityStack stack = mStacks.get(stackNdx);
            if (!isFrontStack(stack)) {
                continue;
            }
            final ActivityRecord resumedActivity = stack.mResumedActivity;
            if (resumedActivity == null || !resumedActivity.idle) {
                return false;
            }
        }
        return true;
    }

    boolean allResumedActivitiesComplete() {
        for (int stackNdx = mStacks.size() - 1; stackNdx >= 0; --stackNdx) {
            final ActivityStack stack = mStacks.get(stackNdx);
            if (isFrontStack(stack)) {
                final ActivityRecord r = stack.mResumedActivity;
                if (r != null && r.state != ActivityState.RESUMED) {
                    return false;
                }
            }
        }
        // TODO: Not sure if this should check if all Paused are complete too.
        switch (mStackState) {
            case STACK_STATE_HOME_TO_BACK:
                if (DEBUG_STACK) Slog.d(TAG, "allResumedActivitiesComplete: mStackState old=" +
                        stackStateToString(STACK_STATE_HOME_TO_BACK) + " new=" +
                        stackStateToString(STACK_STATE_HOME_IN_BACK));
                mStackState = STACK_STATE_HOME_IN_BACK;
                break;
            case STACK_STATE_HOME_TO_FRONT:
                if (DEBUG_STACK) Slog.d(TAG, "allResumedActivitiesComplete: mStackState old=" +
                        stackStateToString(STACK_STATE_HOME_TO_FRONT) + " new=" +
                        stackStateToString(STACK_STATE_HOME_IN_FRONT));
                mStackState = STACK_STATE_HOME_IN_FRONT;
                break;
        }
        return true;
    }

    boolean allResumedActivitiesVisible() {
        for (int stackNdx = mStacks.size() - 1; stackNdx >= 0; --stackNdx) {
            final ActivityStack stack = mStacks.get(stackNdx);
            final ActivityRecord r = stack.mResumedActivity;
            if (r != null && (!r.nowVisible || r.waitingVisible)) {
                return false;
            }
        }
        return true;
    }

    /**
     * Pause all activities in either all of the stacks or just the back stacks.
     * @param userLeaving Passed to pauseActivity() to indicate whether to call onUserLeaving().
     * @return true if any activity was paused as a result of this call.
     */
    boolean pauseBackStacks(boolean userLeaving) {
        boolean someActivityPaused = false;
        for (int stackNdx = mStacks.size() - 1; stackNdx >= 0; --stackNdx) {
            final ActivityStack stack = mStacks.get(stackNdx);
            if (!isFrontStack(stack) && stack.mResumedActivity != null) {
                if (DEBUG_STATES) Slog.d(TAG, "pauseBackStacks: stack=" + stack +
                        " mResumedActivity=" + stack.mResumedActivity);
                stack.startPausingLocked(userLeaving, false);
                someActivityPaused = true;
            }
        }
        return someActivityPaused;
    }

    boolean allPausedActivitiesComplete() {
        boolean pausing = true;
        for (int stackNdx = mStacks.size() - 1; stackNdx >= 0; --stackNdx) {
            final ActivityStack stack = mStacks.get(stackNdx);
            final ActivityRecord r = stack.mPausingActivity;
            if (r != null && r.state != ActivityState.PAUSED
                    && r.state != ActivityState.STOPPED
                    && r.state != ActivityState.STOPPING) {
                if (DEBUG_STATES) {
                    Slog.d(TAG, "allPausedActivitiesComplete: r=" + r + " state=" + r.state);
                    pausing = false;
                } else {
                    return false;
                }
            }
        }
        return pausing;
    }

    void reportActivityVisibleLocked(ActivityRecord r) {
        for (int i = mWaitingActivityVisible.size()-1; i >= 0; i--) {
            WaitResult w = mWaitingActivityVisible.get(i);
            w.timeout = false;
            if (r != null) {
                w.who = new ComponentName(r.info.packageName, r.info.name);
            }
            w.totalTime = SystemClock.uptimeMillis() - w.thisTime;
            w.thisTime = w.totalTime;
        }
        mService.notifyAll();
        dismissKeyguard();
    }

    void reportActivityLaunchedLocked(boolean timeout, ActivityRecord r,
            long thisTime, long totalTime) {
        for (int i = mWaitingActivityLaunched.size() - 1; i >= 0; i--) {
            WaitResult w = mWaitingActivityLaunched.remove(i);
            w.timeout = timeout;
            if (r != null) {
                w.who = new ComponentName(r.info.packageName, r.info.name);
            }
            w.thisTime = thisTime;
            w.totalTime = totalTime;
        }
        mService.notifyAll();
    }

    ActivityRecord topRunningActivityLocked() {
        final ActivityStack focusedStack = getFocusedStack();
        ActivityRecord r = focusedStack.topRunningActivityLocked(null);
        if (r != null) {
            return r;
        }

        for (int stackNdx = mStacks.size() - 1; stackNdx >= 0; --stackNdx) {
            final ActivityStack stack = mStacks.get(stackNdx);
            if (stack != focusedStack && isFrontStack(stack)) {
                r = stack.topRunningActivityLocked(null);
                if (r != null) {
                    return r;
                }
            }
        }
        return null;
    }

    ActivityRecord getTasksLocked(int maxNum, IThumbnailReceiver receiver,
            PendingThumbnailsRecord pending, List<RunningTaskInfo> list) {
        ActivityRecord r = null;

        // Gather all of the running tasks for each stack into runningTaskLists.
        final int numStacks = mStacks.size();
        ArrayList<RunningTaskInfo>[] runningTaskLists = new ArrayList[numStacks];
        for (int stackNdx = numStacks - 1; stackNdx >= 0; --stackNdx) {
            final ActivityStack stack = mStacks.get(stackNdx);
            ArrayList<RunningTaskInfo> stackTaskList = new ArrayList<RunningTaskInfo>();
            runningTaskLists[stackNdx] = stackTaskList;
            final ActivityRecord ar = stack.getTasksLocked(receiver, pending, stackTaskList);
            if (isFrontStack(stack)) {
                r = ar;
            }
        }

        // The lists are already sorted from most recent to oldest. Just pull the most recent off
        // each list and add it to list. Stop when all lists are empty or maxNum reached.
        while (maxNum > 0) {
            long mostRecentActiveTime = Long.MIN_VALUE;
            ArrayList<RunningTaskInfo> selectedStackList = null;
            for (int stackNdx = 0; stackNdx < numStacks; ++stackNdx) {
                ArrayList<RunningTaskInfo> stackTaskList = runningTaskLists[stackNdx];
                if (!stackTaskList.isEmpty()) {
                    final long lastActiveTime = stackTaskList.get(0).lastActiveTime;
                    if (lastActiveTime > mostRecentActiveTime) {
                        mostRecentActiveTime = lastActiveTime;
                        selectedStackList = stackTaskList;
                    }
                }
            }
            if (selectedStackList != null) {
                list.add(selectedStackList.remove(0));
                --maxNum;
            } else {
                break;
            }
        }

        return r;
    }

    ActivityInfo resolveActivity(Intent intent, String resolvedType, int startFlags,
            String profileFile, ParcelFileDescriptor profileFd, int userId) {
        // Collect information about the target of the Intent.
        ActivityInfo aInfo;
        try {
            ResolveInfo rInfo =
                AppGlobals.getPackageManager().resolveIntent(
                        intent, resolvedType,
                        PackageManager.MATCH_DEFAULT_ONLY
                                    | ActivityManagerService.STOCK_PM_FLAGS, userId);
            aInfo = rInfo != null ? rInfo.activityInfo : null;
        } catch (RemoteException e) {
            aInfo = null;
        }

        if (aInfo != null) {
            // Store the found target back into the intent, because now that
            // we have it we never want to do this again.  For example, if the
            // user navigates back to this point in the history, we should
            // always restart the exact same activity.
            intent.setComponent(new ComponentName(
                    aInfo.applicationInfo.packageName, aInfo.name));

            // Don't debug things in the system process
            if ((startFlags&ActivityManager.START_FLAG_DEBUG) != 0) {
                if (!aInfo.processName.equals("system")) {
                    mService.setDebugApp(aInfo.processName, true, false);
                }
            }

            if ((startFlags&ActivityManager.START_FLAG_OPENGL_TRACES) != 0) {
                if (!aInfo.processName.equals("system")) {
                    mService.setOpenGlTraceApp(aInfo.applicationInfo, aInfo.processName);
                }
            }

            if (profileFile != null) {
                if (!aInfo.processName.equals("system")) {
                    mService.setProfileApp(aInfo.applicationInfo, aInfo.processName,
                            profileFile, profileFd,
                            (startFlags&ActivityManager.START_FLAG_AUTO_STOP_PROFILER) != 0);
                }
            }
        }
        return aInfo;
    }

    void startHomeActivity(Intent intent, ActivityInfo aInfo) {
        moveHomeToTop();
        startActivityLocked(null, intent, null, aInfo, null, null, 0, 0, 0, null, 0,
                null, false, null);
    }

    final int startActivityMayWait(IApplicationThread caller, int callingUid,
            String callingPackage, Intent intent, String resolvedType, IBinder resultTo,
            String resultWho, int requestCode, int startFlags, String profileFile,
            ParcelFileDescriptor profileFd, WaitResult outResult, Configuration config,
            Bundle options, int userId) {
        // Refuse possible leaked file descriptors
        if (intent != null && intent.hasFileDescriptors()) {
            throw new IllegalArgumentException("File descriptors passed in Intent");
        }
        boolean componentSpecified = intent.getComponent() != null;

        // Don't modify the client's object!
        intent = new Intent(intent);

        // Collect information about the target of the Intent.
        ActivityInfo aInfo = resolveActivity(intent, resolvedType, startFlags,
                profileFile, profileFd, userId);

        synchronized (mService) {
            int callingPid;
            if (callingUid >= 0) {
                callingPid = -1;
            } else if (caller == null) {
                callingPid = Binder.getCallingPid();
                callingUid = Binder.getCallingUid();
            } else {
                callingPid = callingUid = -1;
            }

            final ActivityStack stack = getFocusedStack();
            stack.mConfigWillChange = config != null
                    && mService.mConfiguration.diff(config) != 0;
            if (DEBUG_CONFIGURATION) Slog.v(TAG,
                    "Starting activity when config will change = " + stack.mConfigWillChange);

            final long origId = Binder.clearCallingIdentity();

            if (aInfo != null &&
                    (aInfo.applicationInfo.flags&ApplicationInfo.FLAG_CANT_SAVE_STATE) != 0) {
                // This may be a heavy-weight process!  Check to see if we already
                // have another, different heavy-weight process running.
                if (aInfo.processName.equals(aInfo.applicationInfo.packageName)) {
                    if (mService.mHeavyWeightProcess != null &&
                            (mService.mHeavyWeightProcess.info.uid != aInfo.applicationInfo.uid ||
                            !mService.mHeavyWeightProcess.processName.equals(aInfo.processName))) {
                        int realCallingUid = callingUid;
                        if (caller != null) {
                            ProcessRecord callerApp = mService.getRecordForAppLocked(caller);
                            if (callerApp != null) {
                                realCallingUid = callerApp.info.uid;
                            } else {
                                Slog.w(TAG, "Unable to find app for caller " + caller
                                      + " (pid=" + callingPid + ") when starting: "
                                      + intent.toString());
                                ActivityOptions.abort(options);
                                return ActivityManager.START_PERMISSION_DENIED;
                            }
                        }

                        IIntentSender target = mService.getIntentSenderLocked(
                                ActivityManager.INTENT_SENDER_ACTIVITY, "android",
                                realCallingUid, userId, null, null, 0, new Intent[] { intent },
                                new String[] { resolvedType }, PendingIntent.FLAG_CANCEL_CURRENT
                                | PendingIntent.FLAG_ONE_SHOT, null);

                        Intent newIntent = new Intent();
                        if (requestCode >= 0) {
                            // Caller is requesting a result.
                            newIntent.putExtra(HeavyWeightSwitcherActivity.KEY_HAS_RESULT, true);
                        }
                        newIntent.putExtra(HeavyWeightSwitcherActivity.KEY_INTENT,
                                new IntentSender(target));
                        if (mService.mHeavyWeightProcess.activities.size() > 0) {
                            ActivityRecord hist = mService.mHeavyWeightProcess.activities.get(0);
                            newIntent.putExtra(HeavyWeightSwitcherActivity.KEY_CUR_APP,
                                    hist.packageName);
                            newIntent.putExtra(HeavyWeightSwitcherActivity.KEY_CUR_TASK,
                                    hist.task.taskId);
                        }
                        newIntent.putExtra(HeavyWeightSwitcherActivity.KEY_NEW_APP,
                                aInfo.packageName);
                        newIntent.setFlags(intent.getFlags());
                        newIntent.setClassName("android",
                                HeavyWeightSwitcherActivity.class.getName());
                        intent = newIntent;
                        resolvedType = null;
                        caller = null;
                        callingUid = Binder.getCallingUid();
                        callingPid = Binder.getCallingPid();
                        componentSpecified = true;
                        try {
                            ResolveInfo rInfo =
                                AppGlobals.getPackageManager().resolveIntent(
                                        intent, null,
                                        PackageManager.MATCH_DEFAULT_ONLY
                                        | ActivityManagerService.STOCK_PM_FLAGS, userId);
                            aInfo = rInfo != null ? rInfo.activityInfo : null;
                            aInfo = mService.getActivityInfoForUser(aInfo, userId);
                        } catch (RemoteException e) {
                            aInfo = null;
                        }
                    }
                }
            }

            int res = startActivityLocked(caller, intent, resolvedType,
                    aInfo, resultTo, resultWho, requestCode, callingPid, callingUid,
                    callingPackage, startFlags, options, componentSpecified, null);

            if (stack.mConfigWillChange) {
                // If the caller also wants to switch to a new configuration,
                // do so now.  This allows a clean switch, as we are waiting
                // for the current activity to pause (so we will not destroy
                // it), and have not yet started the next activity.
                mService.enforceCallingPermission(android.Manifest.permission.CHANGE_CONFIGURATION,
                        "updateConfiguration()");
                stack.mConfigWillChange = false;
                if (DEBUG_CONFIGURATION) Slog.v(TAG,
                        "Updating to new configuration after starting activity.");
                mService.updateConfigurationLocked(config, null, false, false);
            }

            Binder.restoreCallingIdentity(origId);

            if (outResult != null) {
                outResult.result = res;
                if (res == ActivityManager.START_SUCCESS) {
                    mWaitingActivityLaunched.add(outResult);
                    do {
                        try {
                            mService.wait();
                        } catch (InterruptedException e) {
                        }
                    } while (!outResult.timeout && outResult.who == null);
                } else if (res == ActivityManager.START_TASK_TO_FRONT) {
                    ActivityRecord r = stack.topRunningActivityLocked(null);
                    if (r.nowVisible) {
                        outResult.timeout = false;
                        outResult.who = new ComponentName(r.info.packageName, r.info.name);
                        outResult.totalTime = 0;
                        outResult.thisTime = 0;
                    } else {
                        outResult.thisTime = SystemClock.uptimeMillis();
                        mWaitingActivityVisible.add(outResult);
                        do {
                            try {
                                mService.wait();
                            } catch (InterruptedException e) {
                            }
                        } while (!outResult.timeout && outResult.who == null);
                    }
                }
            }

            return res;
        }
    }

    final int startActivities(IApplicationThread caller, int callingUid, String callingPackage,
            Intent[] intents, String[] resolvedTypes, IBinder resultTo,
            Bundle options, int userId) {
        if (intents == null) {
            throw new NullPointerException("intents is null");
        }
        if (resolvedTypes == null) {
            throw new NullPointerException("resolvedTypes is null");
        }
        if (intents.length != resolvedTypes.length) {
            throw new IllegalArgumentException("intents are length different than resolvedTypes");
        }


        int callingPid;
        if (callingUid >= 0) {
            callingPid = -1;
        } else if (caller == null) {
            callingPid = Binder.getCallingPid();
            callingUid = Binder.getCallingUid();
        } else {
            callingPid = callingUid = -1;
        }
        final long origId = Binder.clearCallingIdentity();
        try {
            synchronized (mService) {
                ActivityRecord[] outActivity = new ActivityRecord[1];
                for (int i=0; i<intents.length; i++) {
                    Intent intent = intents[i];
                    if (intent == null) {
                        continue;
                    }

                    // Refuse possible leaked file descriptors
                    if (intent != null && intent.hasFileDescriptors()) {
                        throw new IllegalArgumentException("File descriptors passed in Intent");
                    }

                    boolean componentSpecified = intent.getComponent() != null;

                    // Don't modify the client's object!
                    intent = new Intent(intent);

                    // Collect information about the target of the Intent.
                    ActivityInfo aInfo = resolveActivity(intent, resolvedTypes[i],
                            0, null, null, userId);
                    // TODO: New, check if this is correct
                    aInfo = mService.getActivityInfoForUser(aInfo, userId);

                    if (aInfo != null &&
                            (aInfo.applicationInfo.flags & ApplicationInfo.FLAG_CANT_SAVE_STATE)
                                    != 0) {
                        throw new IllegalArgumentException(
                                "FLAG_CANT_SAVE_STATE not supported here");
                    }

                    Bundle theseOptions;
                    if (options != null && i == intents.length-1) {
                        theseOptions = options;
                    } else {
                        theseOptions = null;
                    }
                    int res = startActivityLocked(caller, intent, resolvedTypes[i],
                            aInfo, resultTo, null, -1, callingPid, callingUid, callingPackage,
                            0, theseOptions, componentSpecified, outActivity);
                    if (res < 0) {
                        return res;
                    }

                    resultTo = outActivity[0] != null ? outActivity[0].appToken : null;
                }
            }
        } finally {
            Binder.restoreCallingIdentity(origId);
        }

        return ActivityManager.START_SUCCESS;
    }

    final boolean realStartActivityLocked(ActivityRecord r,
            ProcessRecord app, boolean andResume, boolean checkConfig)
            throws RemoteException {

        r.startFreezingScreenLocked(app, 0);
        if (false) Slog.d(TAG, "realStartActivity: setting app visibility true");
        mWindowManager.setAppVisibility(r.appToken, true);

        // schedule launch ticks to collect information about slow apps.
        r.startLaunchTickingLocked();

        // Have the window manager re-evaluate the orientation of
        // the screen based on the new activity order.  Note that
        // as a result of this, it can call back into the activity
        // manager with a new orientation.  We don't care about that,
        // because the activity is not currently running so we are
        // just restarting it anyway.
        if (checkConfig) {
            Configuration config = mWindowManager.updateOrientationFromAppTokens(
                    mService.mConfiguration,
                    r.mayFreezeScreenLocked(app) ? r.appToken : null);
            mService.updateConfigurationLocked(config, r, false, false);
        }

        r.app = app;
        app.waitingToKill = null;
        r.launchCount++;
        r.lastLaunchTime = SystemClock.uptimeMillis();

        if (localLOGV) Slog.v(TAG, "Launching: " + r);

        int idx = app.activities.indexOf(r);
        if (idx < 0) {
            app.activities.add(r);
        }
        mService.updateLruProcessLocked(app, true, true);

        final ActivityStack stack = r.task.stack;
        try {
            if (app.thread == null) {
                throw new RemoteException();
            }
            List<ResultInfo> results = null;
            List<Intent> newIntents = null;
            if (andResume) {
                results = r.results;
                newIntents = r.newIntents;
            }
            if (DEBUG_SWITCH) Slog.v(TAG, "Launching: " + r
                    + " icicle=" + r.icicle
                    + " with results=" + results + " newIntents=" + newIntents
                    + " andResume=" + andResume);
            if (andResume) {
                EventLog.writeEvent(EventLogTags.AM_RESTART_ACTIVITY,
                        r.userId, System.identityHashCode(r),
                        r.task.taskId, r.shortComponentName);
            }
            if (r.isHomeActivity() && r.isNotResolverActivity()) {
                // Home process is the root process of the task.
                mService.mHomeProcess = r.task.mActivities.get(0).app;
            }
            mService.ensurePackageDexOpt(r.intent.getComponent().getPackageName());
            r.sleeping = false;
            r.forceNewConfig = false;
            mService.showAskCompatModeDialogLocked(r);
            r.compat = mService.compatibilityInfoForPackageLocked(r.info.applicationInfo);
            String profileFile = null;
            ParcelFileDescriptor profileFd = null;
            boolean profileAutoStop = false;
            if (mService.mProfileApp != null && mService.mProfileApp.equals(app.processName)) {
                if (mService.mProfileProc == null || mService.mProfileProc == app) {
                    mService.mProfileProc = app;
                    profileFile = mService.mProfileFile;
                    profileFd = mService.mProfileFd;
                    profileAutoStop = mService.mAutoStopProfiler;
                }
            }
            app.hasShownUi = true;
            app.pendingUiClean = true;
            if (profileFd != null) {
                try {
                    profileFd = profileFd.dup();
                } catch (IOException e) {
                    if (profileFd != null) {
                        try {
                            profileFd.close();
                        } catch (IOException o) {
                        }
                        profileFd = null;
                    }
                }
            }
            app.forceProcessStateUpTo(ActivityManager.PROCESS_STATE_TOP);
            app.thread.scheduleLaunchActivity(new Intent(r.intent), r.appToken,
                    System.identityHashCode(r), r.info,
                    new Configuration(mService.mConfiguration), r.compat,
                    app.repProcState, r.icicle, results, newIntents, !andResume,
                    mService.isNextTransitionForward(), profileFile, profileFd,
                    profileAutoStop);

            if ((app.info.flags&ApplicationInfo.FLAG_CANT_SAVE_STATE) != 0) {
                // This may be a heavy-weight process!  Note that the package
                // manager will ensure that only activity can run in the main
                // process of the .apk, which is the only thing that will be
                // considered heavy-weight.
                if (app.processName.equals(app.info.packageName)) {
                    if (mService.mHeavyWeightProcess != null
                            && mService.mHeavyWeightProcess != app) {
                        Slog.w(TAG, "Starting new heavy weight process " + app
                                + " when already running "
                                + mService.mHeavyWeightProcess);
                    }
                    mService.mHeavyWeightProcess = app;
                    Message msg = mService.mHandler.obtainMessage(
                            ActivityManagerService.POST_HEAVY_NOTIFICATION_MSG);
                    msg.obj = r;
                    mService.mHandler.sendMessage(msg);
                }
            }

        } catch (RemoteException e) {
            if (r.launchFailed) {
                // This is the second time we failed -- finish activity
                // and give up.
                Slog.e(TAG, "Second failure launching "
                      + r.intent.getComponent().flattenToShortString()
                      + ", giving up", e);
                mService.appDiedLocked(app, app.pid, app.thread);
                stack.requestFinishActivityLocked(r.appToken, Activity.RESULT_CANCELED, null,
                        "2nd-crash", false);
                return false;
            }

            // This is the first time we failed -- restart process and
            // retry.
            app.activities.remove(r);
            throw e;
        }

        r.launchFailed = false;
        if (stack.updateLRUListLocked(r)) {
            Slog.w(TAG, "Activity " + r
                  + " being launched, but already in LRU list");
        }

        if (andResume) {
            // As part of the process of launching, ActivityThread also performs
            // a resume.
            stack.minimalResumeActivityLocked(r);
        } else {
            // This activity is not starting in the resumed state... which
            // should look like we asked it to pause+stop (but remain visible),
            // and it has done so and reported back the current icicle and
            // other state.
            if (DEBUG_STATES) Slog.v(TAG, "Moving to STOPPED: " + r
                    + " (starting in stopped state)");
            r.state = ActivityState.STOPPED;
            r.stopped = true;
        }

        // Launch the new version setup screen if needed.  We do this -after-
        // launching the initial activity (that is, home), so that it can have
        // a chance to initialize itself while in the background, making the
        // switch back to it faster and look better.
        if (isFrontStack(stack)) {
            mService.startSetupActivityLocked();
        }

        return true;
    }

    void startSpecificActivityLocked(ActivityRecord r,
            boolean andResume, boolean checkConfig) {
        // Is this activity's application already running?
        ProcessRecord app = mService.getProcessRecordLocked(r.processName,
                r.info.applicationInfo.uid, true);

        r.task.stack.setLaunchTime(r);

        if (app != null && app.thread != null) {
            try {
                if ((r.info.flags&ActivityInfo.FLAG_MULTIPROCESS) == 0
                        || !"android".equals(r.info.packageName)) {
                    // Don't add this if it is a platform component that is marked
                    // to run in multiple processes, because this is actually
                    // part of the framework so doesn't make sense to track as a
                    // separate apk in the process.
                    app.addPackage(r.info.packageName, mService.mProcessStats);
                }
                realStartActivityLocked(r, app, andResume, checkConfig);
                return;
            } catch (RemoteException e) {
                Slog.w(TAG, "Exception when starting activity "
                        + r.intent.getComponent().flattenToShortString(), e);
            }

            // If a dead object exception was thrown -- fall through to
            // restart the application.
        }

        mService.startProcessLocked(r.processName, r.info.applicationInfo, true, 0,
                "activity", r.intent.getComponent(), false, false, true);
    }

    final int startActivityLocked(IApplicationThread caller,
            Intent intent, String resolvedType, ActivityInfo aInfo, IBinder resultTo,
            String resultWho, int requestCode,
            int callingPid, int callingUid, String callingPackage, int startFlags, Bundle options,
            boolean componentSpecified, ActivityRecord[] outActivity) {
        int err = ActivityManager.START_SUCCESS;

        ProcessRecord callerApp = null;
        if (caller != null) {
            callerApp = mService.getRecordForAppLocked(caller);
            if (callerApp != null) {
                callingPid = callerApp.pid;
                callingUid = callerApp.info.uid;
            } else {
                Slog.w(TAG, "Unable to find app for caller " + caller
                      + " (pid=" + callingPid + ") when starting: "
                      + intent.toString());
                err = ActivityManager.START_PERMISSION_DENIED;
            }
        }

        if (err == ActivityManager.START_SUCCESS) {
            final int userId = aInfo != null ? UserHandle.getUserId(aInfo.applicationInfo.uid) : 0;
            Slog.i(TAG, "START u" + userId + " {" + intent.toShortString(true, true, true, false)
                    + "} from pid " + (callerApp != null ? callerApp.pid : callingPid));
        }

        ActivityRecord sourceRecord = null;
        ActivityRecord resultRecord = null;
        if (resultTo != null) {
            sourceRecord = isInAnyStackLocked(resultTo);
            if (DEBUG_RESULTS) Slog.v(
                TAG, "Will send result to " + resultTo + " " + sourceRecord);
            if (sourceRecord != null) {
                if (requestCode >= 0 && !sourceRecord.finishing) {
                    resultRecord = sourceRecord;
                }
            }
        }
        ActivityStack resultStack = resultRecord == null ? null : resultRecord.task.stack;

        int launchFlags = intent.getFlags();

        if ((launchFlags&Intent.FLAG_ACTIVITY_FORWARD_RESULT) != 0
                && sourceRecord != null) {
            // Transfer the result target from the source activity to the new
            // one being started, including any failures.
            if (requestCode >= 0) {
                ActivityOptions.abort(options);
                return ActivityManager.START_FORWARD_AND_REQUEST_CONFLICT;
            }
            resultRecord = sourceRecord.resultTo;
            resultWho = sourceRecord.resultWho;
            requestCode = sourceRecord.requestCode;
            sourceRecord.resultTo = null;
            if (resultRecord != null) {
                resultRecord.removeResultsLocked(
                    sourceRecord, resultWho, requestCode);
            }
        }

        if (err == ActivityManager.START_SUCCESS && intent.getComponent() == null) {
            // We couldn't find a class that can handle the given Intent.
            // That's the end of that!
            err = ActivityManager.START_INTENT_NOT_RESOLVED;
        }

        if (err == ActivityManager.START_SUCCESS && aInfo == null) {
            // We couldn't find the specific class specified in the Intent.
            // Also the end of the line.
            err = ActivityManager.START_CLASS_NOT_FOUND;
        }

        if (err != ActivityManager.START_SUCCESS) {
            if (resultRecord != null) {
                resultStack.sendActivityResultLocked(-1,
                    resultRecord, resultWho, requestCode,
                    Activity.RESULT_CANCELED, null);
            }
            setDismissKeyguard(false);
            ActivityOptions.abort(options);
            return err;
        }

        final int startAnyPerm = mService.checkPermission(
                START_ANY_ACTIVITY, callingPid, callingUid);
        final int componentPerm = mService.checkComponentPermission(aInfo.permission, callingPid,
                callingUid, aInfo.applicationInfo.uid, aInfo.exported);
        if (startAnyPerm != PERMISSION_GRANTED && componentPerm != PERMISSION_GRANTED) {
            if (resultRecord != null) {
                resultStack.sendActivityResultLocked(-1,
                    resultRecord, resultWho, requestCode,
                    Activity.RESULT_CANCELED, null);
            }
            setDismissKeyguard(false);
            String msg;
            if (!aInfo.exported) {
                msg = "Permission Denial: starting " + intent.toString()
                        + " from " + callerApp + " (pid=" + callingPid
                        + ", uid=" + callingUid + ")"
                        + " not exported from uid " + aInfo.applicationInfo.uid;
            } else {
                msg = "Permission Denial: starting " + intent.toString()
                        + " from " + callerApp + " (pid=" + callingPid
                        + ", uid=" + callingUid + ")"
                        + " requires " + aInfo.permission;
            }
            Slog.w(TAG, msg);
            throw new SecurityException(msg);
        }

        boolean abort = !mService.mIntentFirewall.checkStartActivity(intent, callingUid,
                callingPid, resolvedType, aInfo.applicationInfo);

        if (mService.mController != null) {
            try {
                // The Intent we give to the watcher has the extra data
                // stripped off, since it can contain private information.
                Intent watchIntent = intent.cloneFilter();
                abort |= !mService.mController.activityStarting(watchIntent,
                        aInfo.applicationInfo.packageName);
            } catch (RemoteException e) {
                mService.mController = null;
            }
        }

        if (abort) {
            if (resultRecord != null) {
                resultStack.sendActivityResultLocked(-1, resultRecord, resultWho, requestCode,
                        Activity.RESULT_CANCELED, null);
            }
            // We pretend to the caller that it was really started, but
            // they will just get a cancel result.
            setDismissKeyguard(false);
            ActivityOptions.abort(options);
            return ActivityManager.START_SUCCESS;
        }

        ActivityRecord r = new ActivityRecord(mService, callerApp, callingUid, callingPackage,
                intent, resolvedType, aInfo, mService.mConfiguration,
                resultRecord, resultWho, requestCode, componentSpecified, this);
        if (outActivity != null) {
            outActivity[0] = r;
        }

        final ActivityStack stack = getFocusedStack();
        if (stack.mResumedActivity == null
                || stack.mResumedActivity.info.applicationInfo.uid != callingUid) {
            if (!mService.checkAppSwitchAllowedLocked(callingPid, callingUid, "Activity start")) {
                PendingActivityLaunch pal =
                        new PendingActivityLaunch(r, sourceRecord, startFlags, stack);
                mService.mPendingActivityLaunches.add(pal);
                setDismissKeyguard(false);
                ActivityOptions.abort(options);
                return ActivityManager.START_SWITCHES_CANCELED;
            }
        }

        if (mService.mDidAppSwitch) {
            // This is the second allowed switch since we stopped switches,
            // so now just generally allow switches.  Use case: user presses
            // home (switches disabled, switch to home, mDidAppSwitch now true);
            // user taps a home icon (coming from home so allowed, we hit here
            // and now allow anyone to switch again).
            mService.mAppSwitchesAllowedTime = 0;
        } else {
            mService.mDidAppSwitch = true;
        }

        mService.doPendingActivityLaunchesLocked(false);

        err = startActivityUncheckedLocked(r, sourceRecord, startFlags, true, options);

        if (allPausedActivitiesComplete()) {
            // If someone asked to have the keyguard dismissed on the next
            // activity start, but we are not actually doing an activity
            // switch...  just dismiss the keyguard now, because we
            // probably want to see whatever is behind it.
            dismissKeyguard();
        }
        return err;
    }

    ActivityStack adjustStackFocus(ActivityRecord r) {
        final TaskRecord task = r.task;
        if (r.isApplicationActivity() || (task != null && task.isApplicationTask())) {
            if (task != null) {
                final ActivityStack taskStack = task.stack;
                if (mFocusedStack != taskStack) {
                    if (DEBUG_FOCUS || DEBUG_STACK) Slog.d(TAG,
                            "adjustStackFocus: Setting focused stack to r=" + r + " task=" + task);
                    mFocusedStack = taskStack.isHomeStack() ? null : taskStack;
                } else {
                    if (DEBUG_FOCUS || DEBUG_STACK) Slog.d(TAG,
                        "adjustStackFocus: Focused stack already=" + mFocusedStack);
                }
                return taskStack;
            }

            if (mFocusedStack != null) {
                if (DEBUG_FOCUS || DEBUG_STACK) Slog.d(TAG,
                        "adjustStackFocus: Have a focused stack=" + mFocusedStack);
                return mFocusedStack;
            }

            for (int stackNdx = mStacks.size() - 1; stackNdx > 0; --stackNdx) {
                ActivityStack stack = mStacks.get(stackNdx);
                if (!stack.isHomeStack()) {
                    if (DEBUG_FOCUS || DEBUG_STACK) Slog.d(TAG,
                            "adjustStackFocus: Setting focused stack=" + stack);
                    mFocusedStack = stack;
                    return mFocusedStack;
                }
            }

            // Time to create the first app stack for this user.
            int stackId =
                    mService.createStack(-1, HOME_STACK_ID, StackBox.TASK_STACK_GOES_OVER, 1.0f);
            if (DEBUG_FOCUS || DEBUG_STACK) Slog.d(TAG, "adjustStackFocus: New stack r=" + r +
                    " stackId=" + stackId);
            mFocusedStack = getStack(stackId);
            return mFocusedStack;
        }
        return mHomeStack;
    }

    void setFocusedStack(ActivityRecord r) {
        if (r == null) {
            return;
        }
        if (!r.isApplicationActivity() || (r.task != null && !r.task.isApplicationTask())) {
            if (mStackState != STACK_STATE_HOME_IN_FRONT) {
                if (DEBUG_STACK || DEBUG_FOCUS) Slog.d(TAG, "setFocusedStack: mStackState old=" +
                        stackStateToString(mStackState) + " new=" +
                        stackStateToString(STACK_STATE_HOME_TO_FRONT) +
                        " Callers=" + Debug.getCallers(3));
                mStackState = STACK_STATE_HOME_TO_FRONT;
            }
        } else {
            if (DEBUG_FOCUS || DEBUG_STACK) Slog.d(TAG,
                    "setFocusedStack: Setting focused stack to r=" + r + " task=" + r.task +
                    " Callers=" + Debug.getCallers(3));
            final ActivityStack taskStack = r.task.stack;
            mFocusedStack = taskStack.isHomeStack() ? null : taskStack;
            if (mStackState != STACK_STATE_HOME_IN_BACK) {
                if (DEBUG_STACK) Slog.d(TAG, "setFocusedStack: mStackState old=" +
                        stackStateToString(mStackState) + " new=" +
                        stackStateToString(STACK_STATE_HOME_TO_BACK) +
                        " Callers=" + Debug.getCallers(3));
                mStackState = STACK_STATE_HOME_TO_BACK;
            }
        }
    }

    final int startActivityUncheckedLocked(ActivityRecord r,
            ActivityRecord sourceRecord, int startFlags, boolean doResume,
            Bundle options) {
        final Intent intent = r.intent;
        final int callingUid = r.launchedFromUid;

        int launchFlags = intent.getFlags();

        // We'll invoke onUserLeaving before onPause only if the launching
        // activity did not explicitly state that this is an automated launch.
        mUserLeaving = (launchFlags&Intent.FLAG_ACTIVITY_NO_USER_ACTION) == 0;
        if (DEBUG_USER_LEAVING) Slog.v(TAG, "startActivity() => mUserLeaving=" + mUserLeaving);

        // If the caller has asked not to resume at this point, we make note
        // of this in the record so that we can skip it when trying to find
        // the top running activity.
        if (!doResume) {
            r.delayedResume = true;
        }

        ActivityRecord notTop = (launchFlags&Intent.FLAG_ACTIVITY_PREVIOUS_IS_TOP) != 0 ? r : null;

        // If the onlyIfNeeded flag is set, then we can do this if the activity
        // being launched is the same as the one making the call...  or, as
        // a special case, if we do not know the caller then we count the
        // current top activity as the caller.
        if ((startFlags&ActivityManager.START_FLAG_ONLY_IF_NEEDED) != 0) {
            ActivityRecord checkedCaller = sourceRecord;
            if (checkedCaller == null) {
                checkedCaller = getFocusedStack().topRunningNonDelayedActivityLocked(notTop);
            }
            if (!checkedCaller.realActivity.equals(r.realActivity)) {
                // Caller is not the same as launcher, so always needed.
                startFlags &= ~ActivityManager.START_FLAG_ONLY_IF_NEEDED;
            }
        }

        if (sourceRecord == null) {
            // This activity is not being started from another...  in this
            // case we -always- start a new task.
            if ((launchFlags&Intent.FLAG_ACTIVITY_NEW_TASK) == 0) {
                Slog.w(TAG, "startActivity called from non-Activity context; forcing " +
                        "Intent.FLAG_ACTIVITY_NEW_TASK for: " + intent);
                launchFlags |= Intent.FLAG_ACTIVITY_NEW_TASK;
            }
        } else if (sourceRecord.launchMode == ActivityInfo.LAUNCH_SINGLE_INSTANCE) {
            // The original activity who is starting us is running as a single
            // instance...  this new activity it is starting must go on its
            // own task.
            launchFlags |= Intent.FLAG_ACTIVITY_NEW_TASK;
        } else if (r.launchMode == ActivityInfo.LAUNCH_SINGLE_INSTANCE
                || r.launchMode == ActivityInfo.LAUNCH_SINGLE_TASK) {
            // The activity being started is a single instance...  it always
            // gets launched into its own task.
            launchFlags |= Intent.FLAG_ACTIVITY_NEW_TASK;
        }

        final ActivityStack sourceStack;
        if (sourceRecord != null) {
            if (sourceRecord.finishing) {
                // If the source is finishing, we can't further count it as our source.  This
                // is because the task it is associated with may now be empty and on its way out,
                // so we don't want to blindly throw it in to that task.  Instead we will take
                // the NEW_TASK flow and try to find a task for it.
                if ((launchFlags&Intent.FLAG_ACTIVITY_NEW_TASK) == 0) {
                    Slog.w(TAG, "startActivity called from finishing " + sourceRecord
                            + "; forcing " + "Intent.FLAG_ACTIVITY_NEW_TASK for: " + intent);
                    launchFlags |= Intent.FLAG_ACTIVITY_NEW_TASK;
                }
                sourceRecord = null;
                sourceStack = null;
            } else {
                sourceStack = sourceRecord.task.stack;
            }
        } else {
            sourceStack = null;
        }

        if (r.resultTo != null && (launchFlags&Intent.FLAG_ACTIVITY_NEW_TASK) != 0) {
            // For whatever reason this activity is being launched into a new
            // task...  yet the caller has requested a result back.  Well, that
            // is pretty messed up, so instead immediately send back a cancel
            // and let the new task continue launched as normal without a
            // dependency on its originator.
            Slog.w(TAG, "Activity is launching as a new task, so cancelling activity result.");
            r.resultTo.task.stack.sendActivityResultLocked(-1,
                    r.resultTo, r.resultWho, r.requestCode,
                Activity.RESULT_CANCELED, null);
            r.resultTo = null;
        }

        boolean addingToTask = false;
        boolean movedHome = false;
        TaskRecord reuseTask = null;
        ActivityStack targetStack;
        if (((launchFlags&Intent.FLAG_ACTIVITY_NEW_TASK) != 0 &&
                (launchFlags&Intent.FLAG_ACTIVITY_MULTIPLE_TASK) == 0)
                || r.launchMode == ActivityInfo.LAUNCH_SINGLE_TASK
                || r.launchMode == ActivityInfo.LAUNCH_SINGLE_INSTANCE) {
            // If bring to front is requested, and no result is requested, and
            // we can find a task that was started with this same
            // component, then instead of launching bring that one to the front.
            if (r.resultTo == null) {
                // See if there is a task to bring to the front.  If this is
                // a SINGLE_INSTANCE activity, there can be one and only one
                // instance of it in the history, and it is always in its own
                // unique task, so we do a special search.
                ActivityRecord intentActivity = r.launchMode != ActivityInfo.LAUNCH_SINGLE_INSTANCE
                        ? findTaskLocked(r)
                        : findActivityLocked(intent, r.info);
                if (intentActivity != null) {
                    if (r.task == null) {
                        r.task = intentActivity.task;
                    }
                    targetStack = intentActivity.task.stack;
                    targetStack.mLastPausedActivity = null;
                    if (DEBUG_TASKS) Slog.d(TAG, "Bring to front target: " + targetStack
                            + " from " + intentActivity);
                    moveHomeStack(targetStack.isHomeStack());
                    if (intentActivity.task.intent == null) {
                        // This task was started because of movement of
                        // the activity based on affinity...  now that we
                        // are actually launching it, we can assign the
                        // base intent.
                        intentActivity.task.setIntent(intent, r.info);
                    }
                    // If the target task is not in the front, then we need
                    // to bring it to the front...  except...  well, with
                    // SINGLE_TASK_LAUNCH it's not entirely clear.  We'd like
                    // to have the same behavior as if a new instance was
                    // being started, which means not bringing it to the front
                    // if the caller is not itself in the front.
                    final ActivityStack lastStack = getLastStack();
                    ActivityRecord curTop = lastStack == null?
                            null : lastStack.topRunningNonDelayedActivityLocked(notTop);
                    if (curTop != null && (curTop.task != intentActivity.task ||
                            curTop.task != lastStack.topTask())) {
                        r.intent.addFlags(Intent.FLAG_ACTIVITY_BROUGHT_TO_FRONT);
                        if (sourceRecord == null || (sourceStack.topActivity() != null &&
                                sourceStack.topActivity().task == sourceRecord.task)) {
                            // We really do want to push this one into the
                            // user's face, right now.
                            movedHome = true;
                            targetStack.moveTaskToFrontLocked(intentActivity.task, r, options);
                            if ((launchFlags &
                                    (FLAG_ACTIVITY_NEW_TASK | FLAG_ACTIVITY_TASK_ON_HOME))
                                    == (FLAG_ACTIVITY_NEW_TASK | FLAG_ACTIVITY_TASK_ON_HOME)) {
                                // Caller wants to appear on home activity.
                                intentActivity.task.mOnTopOfHome = true;
                            }
                            options = null;
                        }
                    }
                    // If the caller has requested that the target task be
                    // reset, then do so.
                    if ((launchFlags&Intent.FLAG_ACTIVITY_RESET_TASK_IF_NEEDED) != 0) {
                        intentActivity = targetStack.resetTaskIfNeededLocked(intentActivity, r);
                    }
                    if ((startFlags&ActivityManager.START_FLAG_ONLY_IF_NEEDED) != 0) {
                        // We don't need to start a new activity, and
                        // the client said not to do anything if that
                        // is the case, so this is it!  And for paranoia, make
                        // sure we have correctly resumed the top activity.
                        if (doResume) {
                            resumeTopActivitiesLocked(targetStack, null, options);
                        } else {
                            ActivityOptions.abort(options);
                        }
                        if (r.task == null)  Slog.v(TAG,
                                "startActivityUncheckedLocked: task left null",
                                new RuntimeException("here").fillInStackTrace());
                        return ActivityManager.START_RETURN_INTENT_TO_CALLER;
                    }
                    if ((launchFlags &
                            (Intent.FLAG_ACTIVITY_NEW_TASK|Intent.FLAG_ACTIVITY_CLEAR_TASK))
                            == (Intent.FLAG_ACTIVITY_NEW_TASK|Intent.FLAG_ACTIVITY_CLEAR_TASK)) {
                        // The caller has requested to completely replace any
                        // existing task with its new activity.  Well that should
                        // not be too hard...
                        reuseTask = intentActivity.task;
                        reuseTask.performClearTaskLocked();
                        reuseTask.setIntent(r.intent, r.info);
                    } else if ((launchFlags&Intent.FLAG_ACTIVITY_CLEAR_TOP) != 0
                            || r.launchMode == ActivityInfo.LAUNCH_SINGLE_TASK
                            || r.launchMode == ActivityInfo.LAUNCH_SINGLE_INSTANCE) {
                        // In this situation we want to remove all activities
                        // from the task up to the one being started.  In most
                        // cases this means we are resetting the task to its
                        // initial state.
                        ActivityRecord top =
                                intentActivity.task.performClearTaskLocked(r, launchFlags);
                        if (top != null) {
                            if (top.frontOfTask) {
                                // Activity aliases may mean we use different
                                // intents for the top activity, so make sure
                                // the task now has the identity of the new
                                // intent.
                                top.task.setIntent(r.intent, r.info);
                            }
                            ActivityStack.logStartActivity(EventLogTags.AM_NEW_INTENT,
                                    r, top.task);
                            top.deliverNewIntentLocked(callingUid, r.intent);
                        } else {
                            // A special case: we need to
                            // start the activity because it is not currently
                            // running, and the caller has asked to clear the
                            // current task to have this activity at the top.
                            addingToTask = true;
                            // Now pretend like this activity is being started
                            // by the top of its task, so it is put in the
                            // right place.
                            sourceRecord = intentActivity;
                        }
                    } else if (r.realActivity.equals(intentActivity.task.realActivity)) {
                        // In this case the top activity on the task is the
                        // same as the one being launched, so we take that
                        // as a request to bring the task to the foreground.
                        // If the top activity in the task is the root
                        // activity, deliver this new intent to it if it
                        // desires.
                        if (((launchFlags&Intent.FLAG_ACTIVITY_SINGLE_TOP) != 0
                                || r.launchMode == ActivityInfo.LAUNCH_SINGLE_TOP)
                                && intentActivity.realActivity.equals(r.realActivity)) {
                            ActivityStack.logStartActivity(EventLogTags.AM_NEW_INTENT, r,
                                    intentActivity.task);
                            if (intentActivity.frontOfTask) {
                                intentActivity.task.setIntent(r.intent, r.info);
                            }
                            intentActivity.deliverNewIntentLocked(callingUid, r.intent);
                        } else if (!r.intent.filterEquals(intentActivity.task.intent)) {
                            // In this case we are launching the root activity
                            // of the task, but with a different intent.  We
                            // should start a new instance on top.
                            addingToTask = true;
                            sourceRecord = intentActivity;
                        }
                    } else if ((launchFlags&Intent.FLAG_ACTIVITY_RESET_TASK_IF_NEEDED) == 0) {
                        // In this case an activity is being launched in to an
                        // existing task, without resetting that task.  This
                        // is typically the situation of launching an activity
                        // from a notification or shortcut.  We want to place
                        // the new activity on top of the current task.
                        addingToTask = true;
                        sourceRecord = intentActivity;
                    } else if (!intentActivity.task.rootWasReset) {
                        // In this case we are launching in to an existing task
                        // that has not yet been started from its front door.
                        // The current task has been brought to the front.
                        // Ideally, we'd probably like to place this new task
                        // at the bottom of its stack, but that's a little hard
                        // to do with the current organization of the code so
                        // for now we'll just drop it.
                        intentActivity.task.setIntent(r.intent, r.info);
                    }
                    if (!addingToTask && reuseTask == null) {
                        // We didn't do anything...  but it was needed (a.k.a., client
                        // don't use that intent!)  And for paranoia, make
                        // sure we have correctly resumed the top activity.
                        if (doResume) {
                            targetStack.resumeTopActivityLocked(null, options);
                        } else {
                            ActivityOptions.abort(options);
                        }
                        if (r.task == null)  Slog.v(TAG,
                            "startActivityUncheckedLocked: task left null",
                            new RuntimeException("here").fillInStackTrace());
                        return ActivityManager.START_TASK_TO_FRONT;
                    }
                }
            }
        }

        //String uri = r.intent.toURI();
        //Intent intent2 = new Intent(uri);
        //Slog.i(TAG, "Given intent: " + r.intent);
        //Slog.i(TAG, "URI is: " + uri);
        //Slog.i(TAG, "To intent: " + intent2);

        if (r.packageName != null) {
            // If the activity being launched is the same as the one currently
            // at the top, then we need to check if it should only be launched
            // once.
            ActivityStack topStack = getFocusedStack();
            ActivityRecord top = topStack.topRunningNonDelayedActivityLocked(notTop);
            if (top != null && r.resultTo == null) {
                if (top.realActivity.equals(r.realActivity) && top.userId == r.userId) {
                    if (top.app != null && top.app.thread != null) {
                        if ((launchFlags&Intent.FLAG_ACTIVITY_SINGLE_TOP) != 0
                            || r.launchMode == ActivityInfo.LAUNCH_SINGLE_TOP
                            || r.launchMode == ActivityInfo.LAUNCH_SINGLE_TASK) {
                            ActivityStack.logStartActivity(EventLogTags.AM_NEW_INTENT, top,
                                    top.task);
                            // For paranoia, make sure we have correctly
                            // resumed the top activity.
                            topStack.mLastPausedActivity = null;
                            if (doResume) {
                                resumeTopActivitiesLocked();
                            }
                            ActivityOptions.abort(options);
                            if ((startFlags&ActivityManager.START_FLAG_ONLY_IF_NEEDED) != 0) {
                                // We don't need to start a new activity, and
                                // the client said not to do anything if that
                                // is the case, so this is it!
                                if (r.task == null)  Slog.v(TAG,
                                    "startActivityUncheckedLocked: task left null",
                                    new RuntimeException("here").fillInStackTrace());
                                return ActivityManager.START_RETURN_INTENT_TO_CALLER;
                            }
                            top.deliverNewIntentLocked(callingUid, r.intent);
                            if (r.task == null)  Slog.v(TAG,
                                "startActivityUncheckedLocked: task left null",
                                new RuntimeException("here").fillInStackTrace());
                            return ActivityManager.START_DELIVERED_TO_TOP;
                        }
                    }
                }
            }

        } else {
            if (r.resultTo != null) {
                r.resultTo.task.stack.sendActivityResultLocked(-1, r.resultTo, r.resultWho,
                        r.requestCode, Activity.RESULT_CANCELED, null);
            }
            ActivityOptions.abort(options);
            if (r.task == null)  Slog.v(TAG,
                "startActivityUncheckedLocked: task left null",
                new RuntimeException("here").fillInStackTrace());
            return ActivityManager.START_CLASS_NOT_FOUND;
        }

        boolean newTask = false;
        boolean keepCurTransition = false;

        // Should this be considered a new task?
        if (r.resultTo == null && !addingToTask
                && (launchFlags&Intent.FLAG_ACTIVITY_NEW_TASK) != 0) {
            targetStack = adjustStackFocus(r);
            moveHomeStack(targetStack.isHomeStack());
            if (reuseTask == null) {
                r.setTask(targetStack.createTaskRecord(getNextTaskId(), r.info, intent, true),
                        null, true);
                if (DEBUG_TASKS) Slog.v(TAG, "Starting new activity " + r + " in new task " +
                        r.task);
            } else {
                r.setTask(reuseTask, reuseTask, true);
            }
            newTask = true;
            if (!movedHome) {
                if ((launchFlags &
                        (Intent.FLAG_ACTIVITY_NEW_TASK|Intent.FLAG_ACTIVITY_TASK_ON_HOME))
                        == (Intent.FLAG_ACTIVITY_NEW_TASK|Intent.FLAG_ACTIVITY_TASK_ON_HOME)) {
                    // Caller wants to appear on home activity, so before starting
                    // their own activity we will bring home to the front.
                    r.task.mOnTopOfHome = true;
                }
            }
        } else if (sourceRecord != null) {
            TaskRecord sourceTask = sourceRecord.task;
            targetStack = sourceTask.stack;
            moveHomeStack(targetStack.isHomeStack());
            if (!addingToTask &&
                    (launchFlags&Intent.FLAG_ACTIVITY_CLEAR_TOP) != 0) {
                // In this case, we are adding the activity to an existing
                // task, but the caller has asked to clear that task if the
                // activity is already running.
                ActivityRecord top = sourceTask.performClearTaskLocked(r, launchFlags);
                keepCurTransition = true;
                if (top != null) {
                    ActivityStack.logStartActivity(EventLogTags.AM_NEW_INTENT, r, top.task);
                    top.deliverNewIntentLocked(callingUid, r.intent);
                    // For paranoia, make sure we have correctly
                    // resumed the top activity.
                    targetStack.mLastPausedActivity = null;
                    if (doResume) {
                        targetStack.resumeTopActivityLocked(null);
                    }
                    ActivityOptions.abort(options);
                    if (r.task == null)  Slog.w(TAG,
                        "startActivityUncheckedLocked: task left null",
                        new RuntimeException("here").fillInStackTrace());
                    return ActivityManager.START_DELIVERED_TO_TOP;
                }
            } else if (!addingToTask &&
                    (launchFlags&Intent.FLAG_ACTIVITY_REORDER_TO_FRONT) != 0) {
                // In this case, we are launching an activity in our own task
                // that may already be running somewhere in the history, and
                // we want to shuffle it to the front of the stack if so.
                final ActivityRecord top = sourceTask.findActivityInHistoryLocked(r);
                if (top != null) {
                    final TaskRecord task = top.task;
                    task.moveActivityToFrontLocked(top);
                    ActivityStack.logStartActivity(EventLogTags.AM_NEW_INTENT, r, task);
                    top.updateOptionsLocked(options);
                    top.deliverNewIntentLocked(callingUid, r.intent);
                    targetStack.mLastPausedActivity = null;
                    if (doResume) {
                        targetStack.resumeTopActivityLocked(null);
                    }
                    return ActivityManager.START_DELIVERED_TO_TOP;
                }
            }
            // An existing activity is starting this new activity, so we want
            // to keep the new one in the same task as the one that is starting
            // it.
            r.setTask(sourceTask, sourceRecord.thumbHolder, false);
            if (DEBUG_TASKS) Slog.v(TAG, "Starting new activity " + r
                    + " in existing task " + r.task + " from source " + sourceRecord);

        } else {
            // This not being started from an existing activity, and not part
            // of a new task...  just put it in the top task, though these days
            // this case should never happen.
            targetStack = adjustStackFocus(r);
            moveHomeStack(targetStack.isHomeStack());
            ActivityRecord prev = targetStack.topActivity();
            r.setTask(prev != null ? prev.task
                    : targetStack.createTaskRecord(getNextTaskId(), r.info, intent, true),
                    null, true);
            if (DEBUG_TASKS) Slog.v(TAG, "Starting new activity " + r
                    + " in new guessed " + r.task);
        }

        mService.grantUriPermissionFromIntentLocked(callingUid, r.packageName,
                intent, r.getUriPermissionsLocked());

        if (newTask) {
            EventLog.writeEvent(EventLogTags.AM_CREATE_TASK, r.userId, r.task.taskId);
        }
        ActivityStack.logStartActivity(EventLogTags.AM_CREATE_ACTIVITY, r, r.task);
        targetStack.mLastPausedActivity = null;
        targetStack.startActivityLocked(r, newTask, doResume, keepCurTransition, options);
        mService.setFocusedActivityLocked(r);
        return ActivityManager.START_SUCCESS;
    }

    void acquireLaunchWakelock() {
        if (VALIDATE_WAKE_LOCK_CALLER && Binder.getCallingUid() != Process.myUid()) {
            throw new IllegalStateException("Calling must be system uid");
        }
        mLaunchingActivity.acquire();
        if (!mHandler.hasMessages(LAUNCH_TIMEOUT_MSG)) {
            // To be safe, don't allow the wake lock to be held for too long.
            mHandler.sendEmptyMessageDelayed(LAUNCH_TIMEOUT_MSG, LAUNCH_TIMEOUT);
        }
    }

    // Checked.
    final ActivityRecord activityIdleInternalLocked(final IBinder token, boolean fromTimeout,
            Configuration config) {
        if (localLOGV) Slog.v(TAG, "Activity idle: " + token);

        ArrayList<ActivityRecord> stops = null;
        ArrayList<ActivityRecord> finishes = null;
        ArrayList<UserStartedState> startingUsers = null;
        int NS = 0;
        int NF = 0;
        IApplicationThread sendThumbnail = null;
        boolean booting = false;
        boolean enableScreen = false;
        boolean activityRemoved = false;

        ActivityRecord r = ActivityRecord.forToken(token);
        if (r != null) {
            if (DEBUG_IDLE) Slog.d(TAG, "activityIdleInternalLocked: Callers=" +
                    Debug.getCallers(4));
            mHandler.removeMessages(IDLE_TIMEOUT_MSG, r);
            r.finishLaunchTickingLocked();
            if (fromTimeout) {
                reportActivityLaunchedLocked(fromTimeout, r, -1, -1);
            }

            // This is a hack to semi-deal with a race condition
            // in the client where it can be constructed with a
            // newer configuration from when we asked it to launch.
            // We'll update with whatever configuration it now says
            // it used to launch.
            if (config != null) {
                r.configuration = config;
            }

            // We are now idle.  If someone is waiting for a thumbnail from
            // us, we can now deliver.
            r.idle = true;

            if (r.thumbnailNeeded && r.app != null && r.app.thread != null) {
                sendThumbnail = r.app.thread;
                r.thumbnailNeeded = false;
            }

            //Slog.i(TAG, "IDLE: mBooted=" + mBooted + ", fromTimeout=" + fromTimeout);
            if (!mService.mBooted && isFrontStack(r.task.stack)) {
                mService.mBooted = true;
                enableScreen = true;
            }
        }

        if (allResumedActivitiesIdle()) {
            if (r != null) {
                mService.scheduleAppGcsLocked();
            }

            if (mLaunchingActivity.isHeld()) {
                mHandler.removeMessages(LAUNCH_TIMEOUT_MSG);
                if (VALIDATE_WAKE_LOCK_CALLER &&
                        Binder.getCallingUid() != Process.myUid()) {
                    throw new IllegalStateException("Calling must be system uid");
                }
                mLaunchingActivity.release();
            }
            ensureActivitiesVisibleLocked(null, 0);
        }

        // Atomically retrieve all of the other things to do.
        stops = processStoppingActivitiesLocked(true);
        NS = stops != null ? stops.size() : 0;
        if ((NF=mFinishingActivities.size()) > 0) {
            finishes = new ArrayList<ActivityRecord>(mFinishingActivities);
            mFinishingActivities.clear();
        }

        final ArrayList<ActivityRecord> thumbnails;
        final int NT = mCancelledThumbnails.size();
        if (NT > 0) {
            thumbnails = new ArrayList<ActivityRecord>(mCancelledThumbnails);
            mCancelledThumbnails.clear();
        } else {
            thumbnails = null;
        }

        if (isFrontStack(mHomeStack)) {
            booting = mService.mBooting;
            mService.mBooting = false;
        }

        if (mStartingUsers.size() > 0) {
            startingUsers = new ArrayList<UserStartedState>(mStartingUsers);
            mStartingUsers.clear();
        }

        // Perform the following actions from unsynchronized state.
        final IApplicationThread thumbnailThread = sendThumbnail;
        mHandler.post(new Runnable() {
            @Override
            public void run() {
                if (thumbnailThread != null) {
                    try {
                        thumbnailThread.requestThumbnail(token);
                    } catch (Exception e) {
                        Slog.w(TAG, "Exception thrown when requesting thumbnail", e);
                        mService.sendPendingThumbnail(null, token, null, null, true);
                    }
                }

                // Report back to any thumbnail receivers.
                for (int i = 0; i < NT; i++) {
                    ActivityRecord r = thumbnails.get(i);
                    mService.sendPendingThumbnail(r, null, null, null, true);
                }
            }
        });

        // Stop any activities that are scheduled to do so but have been
        // waiting for the next one to start.
        for (int i = 0; i < NS; i++) {
            r = stops.get(i);
            final ActivityStack stack = r.task.stack;
            if (r.finishing) {
                stack.finishCurrentActivityLocked(r, ActivityStack.FINISH_IMMEDIATELY, false);
            } else {
                stack.stopActivityLocked(r);
            }
        }

        // Finish any activities that are scheduled to do so but have been
        // waiting for the next one to start.
        for (int i = 0; i < NF; i++) {
            r = finishes.get(i);
            activityRemoved |= r.task.stack.destroyActivityLocked(r, true, false, "finish-idle");
        }

        if (booting) {
            mService.finishBooting();
        } else if (startingUsers != null) {
            for (int i = 0; i < startingUsers.size(); i++) {
                mService.finishUserSwitch(startingUsers.get(i));
            }
        }

        mService.trimApplications();
        //dump();
        //mWindowManager.dump();

        if (enableScreen) {
            mService.enableScreenAfterBoot();
        }

        if (activityRemoved) {
            resumeTopActivitiesLocked();
        }

        return r;
    }

    boolean handleAppDiedLocked(ProcessRecord app) {
        boolean hasVisibleActivities = false;
        for (int stackNdx = mStacks.size() - 1; stackNdx >= 0; --stackNdx) {
            hasVisibleActivities |= mStacks.get(stackNdx).handleAppDiedLocked(app);
        }
        return hasVisibleActivities;
    }

    void closeSystemDialogsLocked() {
        final int numStacks = mStacks.size();
        for (int stackNdx = 0; stackNdx < numStacks; ++stackNdx) {
            final ActivityStack stack = mStacks.get(stackNdx);
            stack.closeSystemDialogsLocked();
        }
    }

    void removeUserLocked(int userId) {
        mUserStackInFront.delete(userId);
    }

    /**
     * @return true if some activity was finished (or would have finished if doit were true).
     */
    boolean forceStopPackageLocked(String name, boolean doit, boolean evenPersistent, int userId) {
        boolean didSomething = false;
        final int numStacks = mStacks.size();
        for (int stackNdx = 0; stackNdx < numStacks; ++stackNdx) {
            final ActivityStack stack = mStacks.get(stackNdx);
            if (stack.forceStopPackageLocked(name, doit, evenPersistent, userId)) {
                didSomething = true;
            }
        }
        return didSomething;
    }

    void updatePreviousProcessLocked(ActivityRecord r) {
        // Now that this process has stopped, we may want to consider
        // it to be the previous app to try to keep around in case
        // the user wants to return to it.

        // First, found out what is currently the foreground app, so that
        // we don't blow away the previous app if this activity is being
        // hosted by the process that is actually still the foreground.
        ProcessRecord fgApp = null;
        for (int stackNdx = mStacks.size() - 1; stackNdx >= 0; --stackNdx) {
            final ActivityStack stack = mStacks.get(stackNdx);
            if (isFrontStack(stack)) {
                if (stack.mResumedActivity != null) {
                    fgApp = stack.mResumedActivity.app;
                } else if (stack.mPausingActivity != null) {
                    fgApp = stack.mPausingActivity.app;
                }
                break;
            }
        }

        // Now set this one as the previous process, only if that really
        // makes sense to.
        if (r.app != null && fgApp != null && r.app != fgApp
                && r.lastVisibleTime > mService.mPreviousProcessVisibleTime
                && r.app != mService.mHomeProcess) {
            mService.mPreviousProcess = r.app;
            mService.mPreviousProcessVisibleTime = r.lastVisibleTime;
        }
    }

    boolean resumeTopActivitiesLocked() {
        return resumeTopActivitiesLocked(null, null, null);
    }

    boolean resumeTopActivitiesLocked(ActivityStack targetStack, ActivityRecord target,
            Bundle targetOptions) {
        if (targetStack == null) {
            targetStack = getFocusedStack();
        }
        boolean result = false;
        for (int stackNdx = mStacks.size() - 1; stackNdx >= 0; --stackNdx) {
            final ActivityStack stack = mStacks.get(stackNdx);
            if (isFrontStack(stack)) {
                if (stack == targetStack) {
                    result = stack.resumeTopActivityLocked(target, targetOptions);
                } else {
                    stack.resumeTopActivityLocked(null);
                }
            }
        }
        return result;
    }

    void finishTopRunningActivityLocked(ProcessRecord app) {
        final int numStacks = mStacks.size();
        for (int stackNdx = 0; stackNdx < numStacks; ++stackNdx) {
            final ActivityStack stack = mStacks.get(stackNdx);
            stack.finishTopRunningActivityLocked(app);
        }
    }

    void findTaskToMoveToFrontLocked(int taskId, int flags, Bundle options) {
        for (int stackNdx = mStacks.size() - 1; stackNdx >= 0; --stackNdx) {
            if (mStacks.get(stackNdx).findTaskToMoveToFrontLocked(taskId, flags, options)) {
                if (DEBUG_STACK) Slog.d(TAG, "findTaskToMoveToFront: moved to front of stack=" +
                        mStacks.get(stackNdx));
                return;
            }
        }
    }

    ActivityStack getStack(int stackId) {
        for (int stackNdx = mStacks.size() - 1; stackNdx >= 0; --stackNdx) {
            final ActivityStack stack = mStacks.get(stackNdx);
            if (stack.getStackId() == stackId) {
                return stack;
            }
        }
        return null;
    }

    ArrayList<ActivityStack> getStacks() {
        return new ArrayList<ActivityStack>(mStacks);
    }

    int createStack() {
        while (true) {
            if (++mLastStackId <= HOME_STACK_ID) {
                mLastStackId = HOME_STACK_ID + 1;
            }
            if (getStack(mLastStackId) == null) {
                break;
            }
        }
        mStacks.add(new ActivityStack(mService, mContext, mLooper, mLastStackId));
        return mLastStackId;
    }

    void moveTaskToStack(int taskId, int stackId, boolean toTop) {
        final TaskRecord task = anyTaskForIdLocked(taskId);
        if (task == null) {
            return;
        }
        final ActivityStack stack = getStack(stackId);
        if (stack == null) {
            Slog.w(TAG, "moveTaskToStack: no stack for id=" + stackId);
            return;
        }
        removeTask(task);
        stack.addTask(task, toTop);
        mWindowManager.addTask(taskId, stackId, toTop);
        resumeTopActivitiesLocked();
    }

    ActivityRecord findTaskLocked(ActivityRecord r) {
        if (DEBUG_TASKS) Slog.d(TAG, "Looking for task of " + r);
        for (int stackNdx = mStacks.size() - 1; stackNdx >= 0; --stackNdx) {
            final ActivityStack stack = mStacks.get(stackNdx);
            if (!r.isApplicationActivity() && !stack.isHomeStack()) {
                if (DEBUG_TASKS) Slog.d(TAG, "Skipping stack: " + stack);
                continue;
            }
            final ActivityRecord ar = stack.findTaskLocked(r);
            if (ar != null) {
                return ar;
            }
        }
        if (DEBUG_TASKS) Slog.d(TAG, "No task found");
        return null;
    }

    ActivityRecord findActivityLocked(Intent intent, ActivityInfo info) {
        for (int stackNdx = mStacks.size() - 1; stackNdx >= 0; --stackNdx) {
            final ActivityRecord ar = mStacks.get(stackNdx).findActivityLocked(intent, info);
            if (ar != null) {
                return ar;
            }
        }
        return null;
    }

    void goingToSleepLocked() {
        scheduleSleepTimeout();
        if (!mGoingToSleep.isHeld()) {
            mGoingToSleep.acquire();
            if (mLaunchingActivity.isHeld()) {
                if (VALIDATE_WAKE_LOCK_CALLER && Binder.getCallingUid() != Process.myUid()) {
                    throw new IllegalStateException("Calling must be system uid");
                }
                mLaunchingActivity.release();
                mService.mHandler.removeMessages(LAUNCH_TIMEOUT_MSG);
            }
        }
        checkReadyForSleepLocked();
    }

    boolean shutdownLocked(int timeout) {
        boolean timedout = false;
        goingToSleepLocked();

        final long endTime = System.currentTimeMillis() + timeout;
        while (true) {
            boolean cantShutdown = false;
            for (int stackNdx = mStacks.size() - 1; stackNdx >= 0; --stackNdx) {
                cantShutdown |= mStacks.get(stackNdx).checkReadyForSleepLocked();
            }
            if (cantShutdown) {
                long timeRemaining = endTime - System.currentTimeMillis();
                if (timeRemaining > 0) {
                    try {
                        mService.wait(timeRemaining);
                    } catch (InterruptedException e) {
                    }
                } else {
                    Slog.w(TAG, "Activity manager shutdown timed out");
                    timedout = true;
                    break;
                }
            } else {
                break;
            }
        }

        // Force checkReadyForSleep to complete.
        mSleepTimeout = true;
        checkReadyForSleepLocked();

        return timedout;
    }

    void comeOutOfSleepIfNeededLocked() {
        removeSleepTimeouts();
        if (mGoingToSleep.isHeld()) {
            mGoingToSleep.release();
        }
        for (int stackNdx = mStacks.size() - 1; stackNdx >= 0; --stackNdx) {
            final ActivityStack stack = mStacks.get(stackNdx);
            stack.awakeFromSleepingLocked();
            if (isFrontStack(stack)) {
                resumeTopActivitiesLocked();
            }
        }
        mGoingToSleepActivities.clear();
    }

    void activitySleptLocked(ActivityRecord r) {
        mGoingToSleepActivities.remove(r);
        checkReadyForSleepLocked();
    }

    void checkReadyForSleepLocked() {
        if (!mService.isSleepingOrShuttingDown()) {
            // Do not care.
            return;
        }

        if (!mSleepTimeout) {
            boolean dontSleep = false;
            for (int stackNdx = mStacks.size() - 1; stackNdx >= 0; --stackNdx) {
                dontSleep |= mStacks.get(stackNdx).checkReadyForSleepLocked();
            }

            if (mStoppingActivities.size() > 0) {
                // Still need to tell some activities to stop; can't sleep yet.
                if (DEBUG_PAUSE) Slog.v(TAG, "Sleep still need to stop "
                        + mStoppingActivities.size() + " activities");
                scheduleIdleLocked();
                dontSleep = true;
            }

            if (mGoingToSleepActivities.size() > 0) {
                // Still need to tell some activities to sleep; can't sleep yet.
                if (DEBUG_PAUSE) Slog.v(TAG, "Sleep still need to sleep "
                        + mGoingToSleepActivities.size() + " activities");
                dontSleep = true;
            }

            if (dontSleep) {
                return;
            }
        }

        for (int stackNdx = mStacks.size() - 1; stackNdx >= 0; --stackNdx) {
            mStacks.get(stackNdx).goToSleep();
        }

        removeSleepTimeouts();

        if (mGoingToSleep.isHeld()) {
            mGoingToSleep.release();
        }
        if (mService.mShuttingDown) {
            mService.notifyAll();
        }
    }

    boolean reportResumedActivityLocked(ActivityRecord r) {
        final ActivityStack stack = r.task.stack;
        if (isFrontStack(stack)) {
            mService.updateUsageStats(r, true);
        }
        if (allResumedActivitiesComplete()) {
            ensureActivitiesVisibleLocked(null, 0);
            mWindowManager.executeAppTransition();
            return true;
        }
        return false;
    }

    void handleAppCrashLocked(ProcessRecord app) {
        final int numStacks = mStacks.size();
        for (int stackNdx = 0; stackNdx < numStacks; ++stackNdx) {
            final ActivityStack stack = mStacks.get(stackNdx);
            stack.handleAppCrashLocked(app);
        }
    }

    void ensureActivitiesVisibleLocked(ActivityRecord starting, int configChanges) {
        // First the front stacks. In case any are not fullscreen and are in front of home.
        boolean showHomeBehindStack = false;
        for (int stackNdx = mStacks.size() - 1; stackNdx >= 0; --stackNdx) {
            final ActivityStack stack = mStacks.get(stackNdx);
            if (isFrontStack(stack)) {
                showHomeBehindStack =
                        stack.ensureActivitiesVisibleLocked(starting, configChanges);
            }
        }
        // Now do back stacks.
        for (int stackNdx = mStacks.size() - 1; stackNdx >= 0; --stackNdx) {
            final ActivityStack stack = mStacks.get(stackNdx);
            if (!isFrontStack(stack)) {
                stack.ensureActivitiesVisibleLocked(starting, configChanges, showHomeBehindStack);
            }
        }
    }

    void scheduleDestroyAllActivities(ProcessRecord app, String reason) {
        final int numStacks = mStacks.size();
        for (int stackNdx = 0; stackNdx < numStacks; ++stackNdx) {
            final ActivityStack stack = mStacks.get(stackNdx);
            stack.scheduleDestroyActivities(app, false, reason);
        }
    }

    boolean switchUserLocked(int userId, UserStartedState uss) {
        mUserStackInFront.put(mCurrentUser, getFocusedStack().getStackId());
        final int restoreStackId = mUserStackInFront.get(userId, HOME_STACK_ID);
        mCurrentUser = userId;

        mStartingUsers.add(uss);
        for (int stackNdx = mStacks.size() - 1; stackNdx >= 0; --stackNdx) {
            mStacks.get(stackNdx).switchUserLocked(userId);
        }

        ActivityStack stack = getStack(restoreStackId);
        if (stack == null) {
            stack = mHomeStack;
        }
        final boolean homeInFront = stack.isHomeStack();
        moveHomeStack(homeInFront);
        mWindowManager.moveTaskToTop(stack.topTask().taskId);
        return homeInFront;
    }

    final ArrayList<ActivityRecord> processStoppingActivitiesLocked(boolean remove) {
        int N = mStoppingActivities.size();
        if (N <= 0) return null;

        ArrayList<ActivityRecord> stops = null;

        final boolean nowVisible = allResumedActivitiesVisible();
        for (int i=0; i<N; i++) {
            ActivityRecord s = mStoppingActivities.get(i);
            if (localLOGV) Slog.v(TAG, "Stopping " + s + ": nowVisible="
                    + nowVisible + " waitingVisible=" + s.waitingVisible
                    + " finishing=" + s.finishing);
            if (s.waitingVisible && nowVisible) {
                mWaitingVisibleActivities.remove(s);
                s.waitingVisible = false;
                if (s.finishing) {
                    // If this activity is finishing, it is sitting on top of
                    // everyone else but we now know it is no longer needed...
                    // so get rid of it.  Otherwise, we need to go through the
                    // normal flow and hide it once we determine that it is
                    // hidden by the activities in front of it.
                    if (localLOGV) Slog.v(TAG, "Before stopping, can hide: " + s);
                    mWindowManager.setAppVisibility(s.appToken, false);
                }
            }
            if ((!s.waitingVisible || mService.isSleepingOrShuttingDown()) && remove) {
                if (localLOGV) Slog.v(TAG, "Ready to stop: " + s);
                if (stops == null) {
                    stops = new ArrayList<ActivityRecord>();
                }
                stops.add(s);
                mStoppingActivities.remove(i);
                N--;
                i--;
            }
        }

        return stops;
    }

    void validateTopActivitiesLocked() {
        for (int stackNdx = mStacks.size() - 1; stackNdx >= 0; --stackNdx) {
            final ActivityStack stack = mStacks.get(stackNdx);
            final ActivityRecord r = stack.topRunningActivityLocked(null);
            final ActivityState state = r == null ? ActivityState.DESTROYED : r.state;
            if (isFrontStack(stack)) {
                if (r == null) {
                    Slog.e(TAG, "validateTop...: null top activity, stack=" + stack);
                } else {
                    final ActivityRecord pausing = stack.mPausingActivity;
                    if (pausing != null && pausing == r) {
                        Slog.e(TAG, "validateTop...: top stack has pausing activity r=" + r +
                            " state=" + state);
                    }
                    if (state != ActivityState.INITIALIZING && state != ActivityState.RESUMED) {
                        Slog.e(TAG, "validateTop...: activity in front not resumed r=" + r +
                                " state=" + state);
                    }
                }
            } else {
                final ActivityRecord resumed = stack.mResumedActivity;
                if (resumed != null && resumed == r) {
                    Slog.e(TAG, "validateTop...: back stack has resumed activity r=" + r +
                        " state=" + state);
                }
                if (r != null && (state == ActivityState.INITIALIZING
                        || state == ActivityState.RESUMED)) {
                    Slog.e(TAG, "validateTop...: activity in back resumed r=" + r +
                            " state=" + state);
                }
            }
        }
    }

    private static String stackStateToString(int stackState) {
        switch (stackState) {
            case STACK_STATE_HOME_IN_FRONT: return "STACK_STATE_HOME_IN_FRONT";
            case STACK_STATE_HOME_TO_BACK: return "STACK_STATE_HOME_TO_BACK";
            case STACK_STATE_HOME_IN_BACK: return "STACK_STATE_HOME_IN_BACK";
            case STACK_STATE_HOME_TO_FRONT: return "STACK_STATE_HOME_TO_FRONT";
            default: return "Unknown stackState=" + stackState;
        }
    }

    public void dump(PrintWriter pw, String prefix) {
        pw.print(prefix); pw.print("mDismissKeyguardOnNextActivity=");
                pw.println(mDismissKeyguardOnNextActivity);
        pw.print(prefix); pw.print("mFocusedStack=" + mFocusedStack);
                pw.print(" mStackState="); pw.println(stackStateToString(mStackState));
        pw.print(prefix); pw.println("mSleepTimeout=" + mSleepTimeout);
        pw.print(prefix); pw.println("mCurTaskId=" + mCurTaskId);
        pw.print(prefix); pw.println("mUserStackInFront=" + mUserStackInFront);
    }

    ArrayList<ActivityRecord> getDumpActivitiesLocked(String name) {
        return getFocusedStack().getDumpActivitiesLocked(name);
    }

    static boolean printThisActivity(PrintWriter pw, ActivityRecord activity, String dumpPackage,
            boolean needSep, String prefix) {
        if (activity != null) {
            if (dumpPackage == null || dumpPackage.equals(activity.packageName)) {
                if (needSep) {
                    pw.println();
                }
                pw.print(prefix);
                pw.println(activity);
                return true;
            }
        }
        return false;
    }

    boolean dumpActivitiesLocked(FileDescriptor fd, PrintWriter pw, boolean dumpAll,
            boolean dumpClient, String dumpPackage) {
        boolean printed = false;
        boolean needSep = false;
        final int numStacks = mStacks.size();
        for (int stackNdx = 0; stackNdx < numStacks; ++stackNdx) {
            final ActivityStack stack = mStacks.get(stackNdx);
            StringBuilder stackHeader = new StringBuilder(128);
            stackHeader.append("  Stack #");
            stackHeader.append(mStacks.indexOf(stack));
            stackHeader.append(":");
            printed |= stack.dumpActivitiesLocked(fd, pw, dumpAll, dumpClient, dumpPackage, needSep,
                    stackHeader.toString());
            printed |= dumpHistoryList(fd, pw, stack.mLRUActivities, "    ", "Run", false, !dumpAll,
                    false, dumpPackage, true, "    Running activities (most recent first):", null);

            needSep = printed;
            boolean pr = printThisActivity(pw, stack.mPausingActivity, dumpPackage, needSep,
                    "    mPausingActivity: ");
            if (pr) {
                printed = true;
                needSep = false;
            }
            pr = printThisActivity(pw, stack.mResumedActivity, dumpPackage, needSep,
                    "    mResumedActivity: ");
            if (pr) {
                printed = true;
                needSep = false;
            }
            if (dumpAll) {
                pr = printThisActivity(pw, stack.mLastPausedActivity, dumpPackage, needSep,
                        "    mLastPausedActivity: ");
                if (pr) {
                    printed = true;
                    needSep = true;
                }
                printed |= printThisActivity(pw, stack.mLastNoHistoryActivity, dumpPackage,
                        needSep, "    mLastNoHistoryActivity: ");
            }
            needSep = printed;
        }

        printed |= dumpHistoryList(fd, pw, mFinishingActivities, "  ", "Fin", false, !dumpAll,
                false, dumpPackage, true, "  Activities waiting to finish:", null);
        printed |= dumpHistoryList(fd, pw, mStoppingActivities, "  ", "Stop", false, !dumpAll,
                false, dumpPackage, true, "  Activities waiting to stop:", null);
        printed |= dumpHistoryList(fd, pw, mWaitingVisibleActivities, "  ", "Wait", false, !dumpAll,
                false, dumpPackage, true, "  Activities waiting for another to become visible:",
                null);
        printed |= dumpHistoryList(fd, pw, mGoingToSleepActivities, "  ", "Sleep", false, !dumpAll,
                false, dumpPackage, true, "  Activities waiting to sleep:", null);
        printed |= dumpHistoryList(fd, pw, mGoingToSleepActivities, "  ", "Sleep", false, !dumpAll,
                false, dumpPackage, true, "  Activities waiting to sleep:", null);

        return printed;
    }

    static boolean dumpHistoryList(FileDescriptor fd, PrintWriter pw, List<ActivityRecord> list,
            String prefix, String label, boolean complete, boolean brief, boolean client,
            String dumpPackage, boolean needNL, String header1, String header2) {
        TaskRecord lastTask = null;
        String innerPrefix = null;
        String[] args = null;
        boolean printed = false;
        for (int i=list.size()-1; i>=0; i--) {
            final ActivityRecord r = list.get(i);
            if (dumpPackage != null && !dumpPackage.equals(r.packageName)) {
                continue;
            }
            if (innerPrefix == null) {
                innerPrefix = prefix + "      ";
                args = new String[0];
            }
            printed = true;
            final boolean full = !brief && (complete || !r.isInHistory());
            if (needNL) {
                pw.println("");
                needNL = false;
            }
            if (header1 != null) {
                pw.println(header1);
                header1 = null;
            }
            if (header2 != null) {
                pw.println(header2);
                header2 = null;
            }
            if (lastTask != r.task) {
                lastTask = r.task;
                pw.print(prefix);
                pw.print(full ? "* " : "  ");
                pw.println(lastTask);
                if (full) {
                    lastTask.dump(pw, prefix + "  ");
                } else if (complete) {
                    // Complete + brief == give a summary.  Isn't that obvious?!?
                    if (lastTask.intent != null) {
                        pw.print(prefix); pw.print("  ");
                                pw.println(lastTask.intent.toInsecureStringWithClip());
                    }
                }
            }
            pw.print(prefix); pw.print(full ? "  * " : "    "); pw.print(label);
            pw.print(" #"); pw.print(i); pw.print(": ");
            pw.println(r);
            if (full) {
                r.dump(pw, innerPrefix);
            } else if (complete) {
                // Complete + brief == give a summary.  Isn't that obvious?!?
                pw.print(innerPrefix); pw.println(r.intent.toInsecureString());
                if (r.app != null) {
                    pw.print(innerPrefix); pw.println(r.app);
                }
            }
            if (client && r.app != null && r.app.thread != null) {
                // flush anything that is already in the PrintWriter since the thread is going
                // to write to the file descriptor directly
                pw.flush();
                try {
                    TransferPipe tp = new TransferPipe();
                    try {
                        r.app.thread.dumpActivity(tp.getWriteFd().getFileDescriptor(),
                                r.appToken, innerPrefix, args);
                        // Short timeout, since blocking here can
                        // deadlock with the application.
                        tp.go(fd, 2000);
                    } finally {
                        tp.kill();
                    }
                } catch (IOException e) {
                    pw.println(innerPrefix + "Failure while dumping the activity: " + e);
                } catch (RemoteException e) {
                    pw.println(innerPrefix + "Got a RemoteException while dumping the activity");
                }
                needNL = true;
            }
        }
        return printed;
    }

    void scheduleIdleTimeoutLocked(ActivityRecord next) {
        if (DEBUG_IDLE) Slog.d(TAG, "scheduleIdleTimeoutLocked: Callers=" + Debug.getCallers(4));
        Message msg = mHandler.obtainMessage(IDLE_TIMEOUT_MSG, next);
        mHandler.sendMessageDelayed(msg, IDLE_TIMEOUT);
    }

    final void scheduleIdleLocked() {
        mHandler.sendEmptyMessage(IDLE_NOW_MSG);
    }

    void removeTimeoutsForActivityLocked(ActivityRecord r) {
        if (DEBUG_IDLE) Slog.d(TAG, "removeTimeoutsForActivity: Callers=" + Debug.getCallers(4));
        mHandler.removeMessages(IDLE_TIMEOUT_MSG, r);
    }

    final void scheduleResumeTopActivities() {
        mHandler.sendEmptyMessage(RESUME_TOP_ACTIVITY_MSG);
    }

    void removeSleepTimeouts() {
        mSleepTimeout = false;
        mHandler.removeMessages(SLEEP_TIMEOUT_MSG);
    }

    final void scheduleSleepTimeout() {
        removeSleepTimeouts();
        mHandler.sendEmptyMessageDelayed(SLEEP_TIMEOUT_MSG, SLEEP_TIMEOUT);
    }

    private final class ActivityStackSupervisorHandler extends Handler {

        public ActivityStackSupervisorHandler(Looper looper) {
            super(looper);
        }

        void activityIdleInternal(ActivityRecord r) {
            synchronized (mService) {
                activityIdleInternalLocked(r != null ? r.appToken : null, true, null);
            }
        }

        @Override
        public void handleMessage(Message msg) {
            switch (msg.what) {
                case IDLE_TIMEOUT_MSG: {
                    if (DEBUG_IDLE) Slog.d(TAG, "handleMessage: IDLE_TIMEOUT_MSG: r=" + msg.obj);
                    if (mService.mDidDexOpt) {
                        mService.mDidDexOpt = false;
                        Message nmsg = mHandler.obtainMessage(IDLE_TIMEOUT_MSG);
                        nmsg.obj = msg.obj;
                        mHandler.sendMessageDelayed(nmsg, IDLE_TIMEOUT);
                        return;
                    }
                    // We don't at this point know if the activity is fullscreen,
                    // so we need to be conservative and assume it isn't.
                    activityIdleInternal((ActivityRecord)msg.obj);
                } break;
                case IDLE_NOW_MSG: {
                    if (DEBUG_IDLE) Slog.d(TAG, "handleMessage: IDLE_NOW_MSG: r=" + msg.obj);
                    activityIdleInternal((ActivityRecord)msg.obj);
                } break;
                case RESUME_TOP_ACTIVITY_MSG: {
                    synchronized (mService) {
                        resumeTopActivitiesLocked();
                    }
                } break;
                case SLEEP_TIMEOUT_MSG: {
                    synchronized (mService) {
                        if (mService.isSleepingOrShuttingDown()) {
                            Slog.w(TAG, "Sleep timeout!  Sleeping now.");
                            mSleepTimeout = true;
                            checkReadyForSleepLocked();
                        }
                    }
                } break;
                case LAUNCH_TIMEOUT_MSG: {
                    if (mService.mDidDexOpt) {
                        mService.mDidDexOpt = false;
                        mHandler.sendEmptyMessageDelayed(LAUNCH_TIMEOUT_MSG, LAUNCH_TIMEOUT);
                        return;
                    }
                    synchronized (mService) {
                        if (mLaunchingActivity.isHeld()) {
                            Slog.w(TAG, "Launch timeout has expired, giving up wake lock!");
                            if (VALIDATE_WAKE_LOCK_CALLER
                                    && Binder.getCallingUid() != Process.myUid()) {
                                throw new IllegalStateException("Calling must be system uid");
                            }
                            mLaunchingActivity.release();
                        }
                    }
                } break;
            }
        }
    }
}