summaryrefslogtreecommitdiffstats
path: root/src/com/android/settings/wifi/WifiSettings.java
blob: a4ecf0e9323ec661f6564f271f349b478bfebd0b (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
/*
 * Copyright (C) 2010 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.settings.wifi;

import static android.net.wifi.WifiConfiguration.INVALID_NETWORK_ID;
import static android.os.UserManager.DISALLOW_CONFIG_WIFI;
import android.app.Activity;
import android.app.Dialog;
import android.content.Context;
import android.content.DialogInterface;
import android.content.Intent;
import android.content.res.Resources;
import android.content.res.TypedArray;
import android.location.LocationManager;
import android.net.ConnectivityManager;
import android.net.NetworkInfo;
import android.net.NetworkInfo.State;
import android.net.wifi.WifiConfiguration;
import android.net.wifi.WifiManager;
import android.net.wifi.WpsInfo;
import android.nfc.NfcAdapter;
import android.os.Bundle;
import android.preference.Preference;
import android.preference.PreferenceScreen;
import android.util.Log;
import android.view.ContextMenu;
import android.view.ContextMenu.ContextMenuInfo;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.MenuItem;
import android.view.View;
import android.widget.AdapterView.AdapterContextMenuInfo;
import android.widget.TextView;
import android.widget.Toast;

import com.android.settings.R;
import com.android.settings.RestrictedSettingsFragment;
import com.android.settings.SettingsActivity;
import com.android.settings.search.BaseSearchIndexProvider;
import com.android.settings.search.Indexable;
import com.android.settings.search.SearchIndexableRaw;
import com.android.settingslib.wifi.AccessPoint;
import com.android.settingslib.wifi.AccessPoint.AccessPointListener;
import com.android.settingslib.wifi.WifiTracker;

import java.util.ArrayList;
import java.util.Collection;
import java.util.List;

/**
 * Two types of UI are provided here.
 *
 * The first is for "usual Settings", appearing as any other Setup fragment.
 *
 * The second is for Setup Wizard, with a simplified interface that hides the action bar
 * and menus.
 */
public class WifiSettings extends RestrictedSettingsFragment
        implements DialogInterface.OnClickListener, Indexable, WifiTracker.WifiListener,
        AccessPointListener {

    private static final String TAG = "WifiSettings";

    /* package */ static final int MENU_ID_WPS_PBC = Menu.FIRST;
    private static final int MENU_ID_WPS_PIN = Menu.FIRST + 1;
    private static final int MENU_ID_SAVED_NETWORK = Menu.FIRST + 2;
    /* package */ static final int MENU_ID_ADD_NETWORK = Menu.FIRST + 3;
    private static final int MENU_ID_ADVANCED = Menu.FIRST + 4;
    private static final int MENU_ID_SCAN = Menu.FIRST + 5;
    private static final int MENU_ID_CONNECT = Menu.FIRST + 6;
    private static final int MENU_ID_FORGET = Menu.FIRST + 7;
    private static final int MENU_ID_MODIFY = Menu.FIRST + 8;
    private static final int MENU_ID_WRITE_NFC = Menu.FIRST + 9;
    private static final int MENU_ID_APPS = Menu.FIRST + 10;

    public static final int WIFI_DIALOG_ID = 1;
    /* package */ static final int WPS_PBC_DIALOG_ID = 2;
    private static final int WPS_PIN_DIALOG_ID = 3;
    private static final int WRITE_NFC_DIALOG_ID = 6;

    // Instance state keys
    private static final String SAVE_DIALOG_EDIT_MODE = "edit_mode";
    private static final String SAVE_DIALOG_ACCESS_POINT_STATE = "wifi_ap_state";

    private static boolean savedNetworksExist;

    protected WifiManager mWifiManager;
    private WifiManager.ActionListener mConnectListener;
    private WifiManager.ActionListener mSaveListener;
    private WifiManager.ActionListener mForgetListener;

    private WifiEnabler mWifiEnabler;
    // An access point being editted is stored here.
    private AccessPoint mSelectedAccessPoint;

    private WifiDialog mDialog;
    private WriteWifiConfigToNfcDialog mWifiToNfcDialog;

    private TextView mEmptyView;

    private boolean showAppIcons = false;
    private MenuItem showAppMenuItem = null;

    // this boolean extra specifies whether to disable the Next button when not connected. Used by
    // account creation outside of setup wizard.
    private static final String EXTRA_ENABLE_NEXT_ON_CONNECT = "wifi_enable_next_on_connect";
    // This string extra specifies a network to open the connect dialog on, so the user can enter
    // network credentials.  This is used by quick settings for secured networks.
    private static final String EXTRA_START_CONNECT_SSID = "wifi_start_connect_ssid";

    // should Next button only be enabled when we have a connection?
    private boolean mEnableNextOnConnection;

    // Save the dialog details
    private boolean mDlgEdit;
    private AccessPoint mDlgAccessPoint;
    private Bundle mAccessPointSavedState;

    private WifiTracker mWifiTracker;

    /* End of "used in Wifi Setup context" */

    public WifiSettings() {
        super(DISALLOW_CONFIG_WIFI);
    }

    @Override
    public void onActivityCreated(Bundle savedInstanceState) {
        super.onActivityCreated(savedInstanceState);

        mWifiTracker = new WifiTracker(getActivity(), this, true, true);
        mWifiManager = mWifiTracker.getManager();

        mConnectListener = new WifiManager.ActionListener() {
                                   @Override
                                   public void onSuccess() {
                                   }
                                   @Override
                                   public void onFailure(int reason) {
                                       Activity activity = getActivity();
                                       if (activity != null) {
                                           Toast.makeText(activity,
                                                R.string.wifi_failed_connect_message,
                                                Toast.LENGTH_SHORT).show();
                                       }
                                   }
                               };

        mSaveListener = new WifiManager.ActionListener() {
                                @Override
                                public void onSuccess() {
                                }
                                @Override
                                public void onFailure(int reason) {
                                    Activity activity = getActivity();
                                    if (activity != null) {
                                        Toast.makeText(activity,
                                            R.string.wifi_failed_save_message,
                                            Toast.LENGTH_SHORT).show();
                                    }
                                }
                            };

        mForgetListener = new WifiManager.ActionListener() {
                                   @Override
                                   public void onSuccess() {
                                   }
                                   @Override
                                   public void onFailure(int reason) {
                                       Activity activity = getActivity();
                                       if (activity != null) {
                                           Toast.makeText(activity,
                                               R.string.wifi_failed_forget_message,
                                               Toast.LENGTH_SHORT).show();
                                       }
                                   }
                               };

        if (savedInstanceState != null) {
            mDlgEdit = savedInstanceState.getBoolean(SAVE_DIALOG_EDIT_MODE);
            if (savedInstanceState.containsKey(SAVE_DIALOG_ACCESS_POINT_STATE)) {
                mAccessPointSavedState =
                    savedInstanceState.getBundle(SAVE_DIALOG_ACCESS_POINT_STATE);
            }
        }

        // if we're supposed to enable/disable the Next button based on our current connection
        // state, start it off in the right state
        Intent intent = getActivity().getIntent();
        mEnableNextOnConnection = intent.getBooleanExtra(EXTRA_ENABLE_NEXT_ON_CONNECT, false);

        if (mEnableNextOnConnection) {
            if (hasNextButton()) {
                final ConnectivityManager connectivity = (ConnectivityManager)
                        getActivity().getSystemService(Context.CONNECTIVITY_SERVICE);
                if (connectivity != null) {
                    NetworkInfo info = connectivity.getNetworkInfo(
                            ConnectivityManager.TYPE_WIFI);
                    changeNextButtonState(info.isConnected());
                }
            }
        }

        addPreferencesFromResource(R.xml.wifi_settings);

        mEmptyView = initEmptyView();
        registerForContextMenu(getListView());
        setHasOptionsMenu(true);

        if (intent.hasExtra(EXTRA_START_CONNECT_SSID)) {
            String ssid = intent.getStringExtra(EXTRA_START_CONNECT_SSID);
            onAccessPointsChanged();
            PreferenceScreen preferenceScreen = getPreferenceScreen();
            for (int i = 0; i < preferenceScreen.getPreferenceCount(); i++) {
                Preference preference = preferenceScreen.getPreference(i);
                if (preference instanceof AccessPointPreference) {
                    AccessPoint accessPoint = ((AccessPointPreference) preference).getAccessPoint();
                    if (ssid.equals(accessPoint.getSsid()) && !accessPoint.isSaved()
                            && accessPoint.getSecurity() != AccessPoint.SECURITY_NONE) {
                        onPreferenceTreeClick(preferenceScreen, preference);
                        break;
                    }
                }
            }
        }
    }

    @Override
    public void onDestroyView() {
        super.onDestroyView();

        if (mWifiEnabler != null) {
            mWifiEnabler.teardownSwitchBar();
        }
    }

    @Override
    public void onStart() {
        super.onStart();

        // On/off switch is hidden for Setup Wizard (returns null)
        mWifiEnabler = createWifiEnabler();
    }

    /**
     * @return new WifiEnabler or null (as overridden by WifiSettingsForSetupWizard)
     */
    /* package */ WifiEnabler createWifiEnabler() {
        final SettingsActivity activity = (SettingsActivity) getActivity();
        return new WifiEnabler(activity, activity.getSwitchBar());
    }

    @Override
    public void onResume() {
        final Activity activity = getActivity();
        super.onResume();
        if (mWifiEnabler != null) {
            mWifiEnabler.resume(activity);
        }

        mWifiTracker.startTracking();
    }

    @Override
    public void onPause() {
        super.onPause();
        if (mWifiEnabler != null) {
            mWifiEnabler.pause();
        }

        mWifiTracker.stopTracking();
    }

    @Override
    public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) {
        // If the user is not allowed to configure wifi, do not show the menu.
        if (isUiRestricted()) return;

        addOptionsMenuItems(menu);
        super.onCreateOptionsMenu(menu, inflater);
    }

    /**
     * @param menu
     */
    void addOptionsMenuItems(Menu menu) {
        final boolean wifiIsEnabled = mWifiTracker.isWifiEnabled();
        TypedArray ta = getActivity().getTheme().obtainStyledAttributes(
                new int[] {R.attr.ic_menu_add, R.attr.ic_wps});
        menu.add(Menu.NONE, MENU_ID_ADD_NETWORK, 0, R.string.wifi_add_network)
                .setIcon(ta.getDrawable(0))
                .setEnabled(wifiIsEnabled)
                .setShowAsAction(MenuItem.SHOW_AS_ACTION_NEVER);
        if (savedNetworksExist) {
            menu.add(Menu.NONE, MENU_ID_SAVED_NETWORK, 0, R.string.wifi_saved_access_points_label)
                    .setIcon(ta.getDrawable(0))
                    .setEnabled(wifiIsEnabled)
                    .setShowAsAction(MenuItem.SHOW_AS_ACTION_NEVER);
        }
        menu.add(Menu.NONE, MENU_ID_SCAN, 0, R.string.menu_stats_refresh)
               .setEnabled(wifiIsEnabled)
               .setShowAsAction(MenuItem.SHOW_AS_ACTION_NEVER);
        menu.add(Menu.NONE, MENU_ID_ADVANCED, 0, R.string.wifi_menu_advanced)
                .setShowAsAction(MenuItem.SHOW_AS_ACTION_NEVER);
        showAppMenuItem = menu.add(Menu.NONE, MENU_ID_APPS, 0, R.string.wifi_menu_apps);
        showAppMenuItem.setShowAsAction(MenuItem.SHOW_AS_ACTION_NEVER);
        ta.recycle();
    }

    @Override
    public void onSaveInstanceState(Bundle outState) {
        super.onSaveInstanceState(outState);

        // If the dialog is showing, save its state.
        if (mDialog != null && mDialog.isShowing()) {
            outState.putBoolean(SAVE_DIALOG_EDIT_MODE, mDlgEdit);
            if (mDlgAccessPoint != null) {
                mAccessPointSavedState = new Bundle();
                mDlgAccessPoint.saveWifiState(mAccessPointSavedState);
                outState.putBundle(SAVE_DIALOG_ACCESS_POINT_STATE, mAccessPointSavedState);
            }
        }
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // If the user is not allowed to configure wifi, do not handle menu selections.
        if (isUiRestricted()) return false;

        switch (item.getItemId()) {
            case MENU_ID_WPS_PBC:
                showDialog(WPS_PBC_DIALOG_ID);
                return true;
                /*
            case MENU_ID_P2P:
                if (getActivity() instanceof SettingsActivity) {
                    ((SettingsActivity) getActivity()).startPreferencePanel(
                            WifiP2pSettings.class.getCanonicalName(),
                            null,
                            R.string.wifi_p2p_settings_title, null,
                            this, 0);
                } else {
                    startFragment(this, WifiP2pSettings.class.getCanonicalName(),
                            R.string.wifi_p2p_settings_title, -1, null);
                }
                return true;
                */
            case MENU_ID_WPS_PIN:
                showDialog(WPS_PIN_DIALOG_ID);
                return true;
            case MENU_ID_SCAN:
                mWifiTracker.forceScan();
                return true;
            case MENU_ID_ADD_NETWORK:
                if (mWifiTracker.isWifiEnabled()) {
                    onAddNetworkPressed();
                }
                return true;
            case MENU_ID_SAVED_NETWORK:
                if (getActivity() instanceof SettingsActivity) {
                    ((SettingsActivity) getActivity()).startPreferencePanel(
                            SavedAccessPointsWifiSettings.class.getCanonicalName(), null,
                            R.string.wifi_saved_access_points_titlebar, null, this, 0);
                } else {
                    startFragment(this, SavedAccessPointsWifiSettings.class.getCanonicalName(),
                            R.string.wifi_saved_access_points_titlebar,
                            -1 /* Do not request a result */, null);
                }
                return true;
            case MENU_ID_ADVANCED:
                if (getActivity() instanceof SettingsActivity) {
                    ((SettingsActivity) getActivity()).startPreferencePanel(
                            AdvancedWifiSettings.class.getCanonicalName(), null,
                            R.string.wifi_advanced_titlebar, null, this, 0);
                } else {
                    startFragment(this, AdvancedWifiSettings.class.getCanonicalName(),
                            R.string.wifi_advanced_titlebar, -1 /* Do not request a results */,
                            null);
                }
                return true;
            case MENU_ID_APPS:
                showAppIcons = !showAppIcons;

                if (showAppIcons) {
                    showAppMenuItem.setTitle(R.string.wifi_menu_apps_strength);
                } else {
                    showAppMenuItem.setTitle(R.string.wifi_menu_apps);
                }
                onAccessPointsChanged();
                return true;
        }
        return super.onOptionsItemSelected(item);
    }

    @Override
    public void onCreateContextMenu(ContextMenu menu, View view, ContextMenuInfo info) {
        if (info instanceof AdapterContextMenuInfo) {
            Preference preference = (Preference) getListView().getItemAtPosition(
                    ((AdapterContextMenuInfo) info).position);

            if (preference instanceof AccessPointPreference) {
                mSelectedAccessPoint = ((AccessPointPreference) preference).getAccessPoint();
                menu.setHeaderTitle(mSelectedAccessPoint.getSsid());
                if (mSelectedAccessPoint.isConnectable()) {
                    menu.add(Menu.NONE, MENU_ID_CONNECT, 0, R.string.wifi_menu_connect);
                }

                if (mSelectedAccessPoint.isSaved() || mSelectedAccessPoint.isEphemeral()) {
                    // Allow forgetting a network if either the network is saved or ephemerally
                    // connected. (In the latter case, "forget" blacklists the network so it won't
                    // be used again, ephemerally).
                    menu.add(Menu.NONE, MENU_ID_FORGET, 0, R.string.wifi_menu_forget);
                }
                if (mSelectedAccessPoint.isSaved()) {
                    menu.add(Menu.NONE, MENU_ID_MODIFY, 0, R.string.wifi_menu_modify);
                    NfcAdapter nfcAdapter = NfcAdapter.getDefaultAdapter(getActivity());
                    if (nfcAdapter != null && nfcAdapter.isEnabled() &&
                            mSelectedAccessPoint.getSecurity() != AccessPoint.SECURITY_NONE) {
                        // Only allow writing of NFC tags for password-protected networks.
                        menu.add(Menu.NONE, MENU_ID_WRITE_NFC, 0, R.string.wifi_menu_write_to_nfc);
                    }
                }
            }
        }
    }

    @Override
    public boolean onContextItemSelected(MenuItem item) {
        if (mSelectedAccessPoint == null) {
            return super.onContextItemSelected(item);
        }
        switch (item.getItemId()) {
            case MENU_ID_CONNECT: {
                if (mSelectedAccessPoint.isSaved()) {
                    connect(mSelectedAccessPoint.getConfig());
                } else if (mSelectedAccessPoint.getSecurity() != AccessPoint.SECURITY_NONE) {
                    /** Bypass dialog for unsecured networks */
                    mSelectedAccessPoint.generateOpenNetworkConfig();
                    connect(mSelectedAccessPoint.getConfig());
                } else {
                    showDialog(mSelectedAccessPoint, true);
                }
                return true;
            }
            case MENU_ID_FORGET: {
                forget();
                return true;
            }
            case MENU_ID_MODIFY: {
                showDialog(mSelectedAccessPoint, true);
                return true;
            }
            case MENU_ID_WRITE_NFC:
                showDialog(WRITE_NFC_DIALOG_ID);
                return true;

        }
        return super.onContextItemSelected(item);
    }

    @Override
    public boolean onPreferenceTreeClick(PreferenceScreen screen, Preference preference) {
        if (preference instanceof AccessPointPreference) {
            mSelectedAccessPoint = ((AccessPointPreference) preference).getAccessPoint();
            /** Bypass dialog for unsecured, unsaved, and inactive networks */
            if (mSelectedAccessPoint.getSecurity() == AccessPoint.SECURITY_NONE &&
                    !mSelectedAccessPoint.isSaved() && !mSelectedAccessPoint.isActive()) {
                mSelectedAccessPoint.generateOpenNetworkConfig();
                if (!savedNetworksExist) {
                    savedNetworksExist = true;
                    getActivity().invalidateOptionsMenu();
                }
                connect(mSelectedAccessPoint.getConfig());
            } else {
                showDialog(mSelectedAccessPoint, false);
            }
        } else {
            return super.onPreferenceTreeClick(screen, preference);
        }
        return true;
    }

    private void showDialog(AccessPoint accessPoint, boolean edit) {
        if (mDialog != null) {
            removeDialog(WIFI_DIALOG_ID);
            mDialog = null;
        }

        // Save the access point and edit mode
        mDlgAccessPoint = accessPoint;
        mDlgEdit = edit;

        showDialog(WIFI_DIALOG_ID);
    }

    @Override
    public Dialog onCreateDialog(int dialogId) {
        switch (dialogId) {
            case WIFI_DIALOG_ID:
                AccessPoint ap = mDlgAccessPoint; // For manual launch
                if (ap == null) { // For re-launch from saved state
                    if (mAccessPointSavedState != null) {
                        ap = new AccessPoint(getActivity(), mAccessPointSavedState);
                        // For repeated orientation changes
                        mDlgAccessPoint = ap;
                        // Reset the saved access point data
                        mAccessPointSavedState = null;
                    }
                }
                // If it's null, fine, it's for Add Network
                mSelectedAccessPoint = ap;
                mDialog = new WifiDialog(getActivity(), this, ap, mDlgEdit);
                return mDialog;
            case WPS_PBC_DIALOG_ID:
                return new WpsDialog(getActivity(), WpsInfo.PBC);
            case WPS_PIN_DIALOG_ID:
                return new WpsDialog(getActivity(), WpsInfo.DISPLAY);
            case WRITE_NFC_DIALOG_ID:
                if (mSelectedAccessPoint != null) {
                    mWifiToNfcDialog = new WriteWifiConfigToNfcDialog(
                            getActivity(), mSelectedAccessPoint, mWifiManager);
                    return mWifiToNfcDialog;
                }

        }
        return super.onCreateDialog(dialogId);
    }

    /**
     * Shows the latest access points available with supplemental information like
     * the strength of network and the security for it.
     */
    @Override
    public void onAccessPointsChanged() {
        // Safeguard from some delayed event handling
        if (getActivity() == null) return;

        if (isUiRestricted()) {
            addMessagePreference(R.string.wifi_empty_list_user_restricted);
            return;
        }
        final int wifiState = mWifiManager.getWifiState();

        switch (wifiState) {
            case WifiManager.WIFI_STATE_ENABLED:
                // AccessPoints are automatically sorted with TreeSet.
                final Collection<AccessPoint> accessPoints =
                        mWifiTracker.getAccessPoints();
                getPreferenceScreen().removeAll();
                if (accessPoints.size() == 0) {
                    addMessagePreference(R.string.wifi_empty_list_wifi_on);
                }

                for (AccessPoint accessPoint : accessPoints) {
                    // Ignore access points that are out of range.
                    if (accessPoint.getLevel() != -1) {
                        AccessPointPreference preference = new AccessPointPreference(accessPoint,
                                getActivity());
                        if (showAppIcons) {
                            preference.showAppIcon();
                        }

                        getPreferenceScreen().addPreference(preference);
                        accessPoint.setListener(this);
                    }
                }
                break;

            case WifiManager.WIFI_STATE_ENABLING:
                getPreferenceScreen().removeAll();
                break;

            case WifiManager.WIFI_STATE_DISABLING:
                addMessagePreference(R.string.wifi_stopping);
                break;

            case WifiManager.WIFI_STATE_DISABLED:
                setOffMessage();
                break;
        }
        // Update "Saved Networks" menu option.
        if (savedNetworksExist != mWifiTracker.doSavedNetworksExist()) {
            savedNetworksExist = !savedNetworksExist;
            getActivity().invalidateOptionsMenu();
        }
    }

    protected TextView initEmptyView() {
        TextView emptyView = (TextView) getActivity().findViewById(android.R.id.empty);
        getListView().setEmptyView(emptyView);
        return emptyView;
    }

    private void setOffMessage() {
        if (mEmptyView != null) {
            mEmptyView.setText(R.string.wifi_empty_list_wifi_off);
            if (android.provider.Settings.Global.getInt(getActivity().getContentResolver(),
                    android.provider.Settings.Global.WIFI_SCAN_ALWAYS_AVAILABLE, 0) == 1) {
                mEmptyView.append("\n\n");
                int resId;
                if (android.provider.Settings.Secure.isLocationProviderEnabled(
                        getActivity().getContentResolver(), LocationManager.NETWORK_PROVIDER)) {
                    resId = R.string.wifi_scan_notify_text_location_on;
                } else {
                    resId = R.string.wifi_scan_notify_text_location_off;
                }
                CharSequence charSeq = getText(resId);
                mEmptyView.append(charSeq);
            }
        }
        getPreferenceScreen().removeAll();
    }

    private void addMessagePreference(int messageId) {
        if (mEmptyView != null) mEmptyView.setText(messageId);
        getPreferenceScreen().removeAll();
    }

    @Override
    public void onWifiStateChanged(int state) {
        Activity activity = getActivity();
        if (activity != null) {
            activity.invalidateOptionsMenu();
        }

        switch (state) {
            case WifiManager.WIFI_STATE_ENABLING:
                addMessagePreference(R.string.wifi_starting);
                break;

            case WifiManager.WIFI_STATE_DISABLED:
                setOffMessage();
                break;
        }
    }

    @Override
    public void onConnectedChanged() {
        changeNextButtonState(mWifiTracker.isConnected());
    }

    /**
     * Renames/replaces "Next" button when appropriate. "Next" button usually exists in
     * Wifi setup screens, not in usual wifi settings screen.
     *
     * @param enabled true when the device is connected to a wifi network.
     */
    private void changeNextButtonState(boolean enabled) {
        if (mEnableNextOnConnection && hasNextButton()) {
            getNextButton().setEnabled(enabled);
        }
    }

    @Override
    public void onClick(DialogInterface dialogInterface, int button) {
        if (button == WifiDialog.BUTTON_FORGET && mSelectedAccessPoint != null) {
            forget();
        } else if (button == WifiDialog.BUTTON_SUBMIT) {
            if (mDialog != null) {
                submit(mDialog.getController());
            }
        }
    }

    /* package */ void submit(WifiConfigController configController) {

        final WifiConfiguration config = configController.getConfig();

        if (config == null) {
            if (mSelectedAccessPoint != null
                    && mSelectedAccessPoint.isSaved()) {
                connect(mSelectedAccessPoint.getConfig());
            }
        } else if (config.networkId != INVALID_NETWORK_ID) {
            if (mSelectedAccessPoint != null) {
                mWifiManager.save(config, mSaveListener);
            }
        } else {
            if (configController.isEdit()) {
                mWifiManager.save(config, mSaveListener);
            } else {
                connect(config);
            }
        }

        mWifiTracker.resumeScanning();
    }

    /* package */ void forget() {
        if (!mSelectedAccessPoint.isSaved()) {
            if (mSelectedAccessPoint.getNetworkInfo().getState() != State.DISCONNECTED) {
                // Network is active but has no network ID - must be ephemeral.
                mWifiManager.disableEphemeralNetwork(
                        AccessPoint.convertToQuotedString(mSelectedAccessPoint.getSsid()));
            } else {
                // Should not happen, but a monkey seems to trigger it
                Log.e(TAG, "Failed to forget invalid network " + mSelectedAccessPoint.getConfig());
                return;
            }
        } else {
            mWifiManager.forget(mSelectedAccessPoint.getConfig().networkId, mForgetListener);
        }

        mWifiTracker.resumeScanning();

        // We need to rename/replace "Next" button in wifi setup context.
        changeNextButtonState(false);
    }

    protected void connect(final WifiConfiguration config) {
        mWifiManager.connect(config, mConnectListener);
    }

    protected void connect(final int networkId) {
        mWifiManager.connect(networkId, mConnectListener);
    }

    /**
     * Refreshes acccess points and ask Wifi module to scan networks again.
     */
    /* package */ void refreshAccessPoints() {
        mWifiTracker.resumeScanning();

        getPreferenceScreen().removeAll();
    }

    /**
     * Called when "add network" button is pressed.
     */
    /* package */ void onAddNetworkPressed() {
        // No exact access point is selected.
        mSelectedAccessPoint = null;
        showDialog(null, true);
    }

    /* package */ int getAccessPointsCount() {
        final boolean wifiIsEnabled = mWifiTracker.isWifiEnabled();
        if (wifiIsEnabled) {
            return getPreferenceScreen().getPreferenceCount();
        } else {
            return 0;
        }
    }

    /**
     * Requests wifi module to pause wifi scan. May be ignored when the module is disabled.
     */
    /* package */ void pauseWifiScan() {
        mWifiTracker.pauseScanning();
    }

    /**
     * Requests wifi module to resume wifi scan. May be ignored when the module is disabled.
     */
    /* package */ void resumeWifiScan() {
        mWifiTracker.resumeScanning();
    }

    @Override
    protected int getHelpResource() {
        return R.string.help_url_wifi;
    }

    @Override
    public void onAccessPointChanged(AccessPoint accessPoint) {
        ((AccessPointPreference) accessPoint.getTag()).refresh();
    }

    @Override
    public void onLevelChanged(AccessPoint accessPoint) {
        ((AccessPointPreference) accessPoint.getTag()).onLevelChanged();
    }

    public static final SearchIndexProvider SEARCH_INDEX_DATA_PROVIDER =
        new BaseSearchIndexProvider() {
            @Override
            public List<SearchIndexableRaw> getRawDataToIndex(Context context, boolean enabled) {
                final List<SearchIndexableRaw> result = new ArrayList<SearchIndexableRaw>();
                final Resources res = context.getResources();

                // Add fragment title
                SearchIndexableRaw data = new SearchIndexableRaw(context);
                data.title = res.getString(R.string.wifi_settings);
                data.screenTitle = res.getString(R.string.wifi_settings);
                data.keywords = res.getString(R.string.keywords_wifi);
                result.add(data);

                // Add saved Wi-Fi access points
                final Collection<AccessPoint> accessPoints =
                        WifiTracker.getCurrentAccessPoints(context, true, false);
                for (AccessPoint accessPoint : accessPoints) {
                    data = new SearchIndexableRaw(context);
                    data.title = accessPoint.getSsid();
                    data.screenTitle = res.getString(R.string.wifi_settings);
                    data.enabled = enabled;
                    result.add(data);
                }

                return result;
            }
        };
}