Support double-tap home to go to recents.

Add config resources to enable the following behavior for
certain devices:

* press home - go home
* long-press home - launch assist intent
* double-tap home - open recents

Bug: 8891502
Change-Id: I4564d9e4d127f782ed5bd8eb613ef8f2255176cc
(cherry picked from commit b7805698035622a633b2d76f7ca60169aaa9f0ca)

1 files changed, 143 insertions, 92 deletions

diff --git a/policy/src/com/android/internal/policy/impl/PhoneWindowManager.java b/policy/src/com/android/internal/policy/impl/PhoneWindowManager.java
index ba51671..a4275a3 100644
--- a/policy/src/com/android/internal/policy/impl/PhoneWindowManager.java
+++ b/policy/src/com/android/internal/policy/impl/PhoneWindowManager.java
@@ -141,6 +141,10 @@ public class PhoneWindowManager implements WindowManagerPolicy {
     // core/res/res/values/config.xml
     static final int LONG_PRESS_HOME_NOTHING = 0;
     static final int LONG_PRESS_HOME_RECENT_SYSTEM_UI = 1;
+    static final int LONG_PRESS_HOME_ASSIST = 2;
+
+    static final int DOUBLE_TAP_HOME_NOTHING = 0;
+    static final int DOUBLE_TAP_HOME_RECENT_SYSTEM_UI = 1;
 
     static final int APPLICATION_MEDIA_SUBLAYER = -2;
     static final int APPLICATION_MEDIA_OVERLAY_SUBLAYER = -1;
@@ -195,6 +199,7 @@ public class PhoneWindowManager implements WindowManagerPolicy {
     WindowManagerFuncs mWindowManagerFuncs;
     PowerManager mPowerManager;
     IStatusBarService mStatusBarService;
+    boolean mPreloadedRecentApps;
     final Object mServiceAquireLock = new Object();
     Vibrator mVibrator; // Vibrator for giving feedback of orientation changes
     SearchManager mSearchManager;
@@ -399,7 +404,8 @@ public class PhoneWindowManager implements WindowManagerPolicy {
     boolean mShowingDream;
     boolean mDreamingLockscreen;
     boolean mHomePressed;
-    boolean mHomeLongPressed;
+    boolean mHomeConsumed;
+    boolean mHomeDoubleTapPending;
     Intent mHomeIntent;
     Intent mCarDockIntent;
     Intent mDeskDockIntent;
@@ -432,7 +438,10 @@ public class PhoneWindowManager implements WindowManagerPolicy {
     int mOverscanBottom = 0;
 
     // What we do when the user long presses on home
-    private int mLongPressOnHomeBehavior = -1;
+    private int mLongPressOnHomeBehavior;
+
+    // What we do when the user double-taps on home
+    private int mDoubleTapOnHomeBehavior;
 
     // Screenshot trigger states
     // Time to volume and power must be pressed within this interval of each other.
@@ -743,36 +752,35 @@ public class PhoneWindowManager implements WindowManagerPolicy {
     }
 
     private void handleLongPressOnHome() {
-        // We can't initialize this in init() since the configuration hasn't been loaded yet.
-        if (mLongPressOnHomeBehavior < 0) {
-            mLongPressOnHomeBehavior
-                    = mContext.getResources().getInteger(R.integer.config_longPressOnHomeBehavior);
-            if (mLongPressOnHomeBehavior < LONG_PRESS_HOME_NOTHING ||
-                    mLongPressOnHomeBehavior > LONG_PRESS_HOME_RECENT_SYSTEM_UI) {
-                mLongPressOnHomeBehavior = LONG_PRESS_HOME_NOTHING;
-            }
-        }
-
         if (mLongPressOnHomeBehavior != LONG_PRESS_HOME_NOTHING) {
+            mHomeConsumed = true;
             performHapticFeedbackLw(null, HapticFeedbackConstants.LONG_PRESS, false);
-            sendCloseSystemWindows(SYSTEM_DIALOG_REASON_RECENT_APPS);
 
-            // Eat the longpress so it won't dismiss the recent apps dialog when
-            // the user lets go of the home key
-            mHomeLongPressed = true;
-            try {
-                IStatusBarService statusbar = getStatusBarService();
-                if (statusbar != null) {
-                    statusbar.toggleRecentApps();
-                }
-            } catch (RemoteException e) {
-                Slog.e(TAG, "RemoteException when showing recent apps", e);
-                // re-acquire status bar service next time it is needed.
-                mStatusBarService = null;
+            if (mLongPressOnHomeBehavior == LONG_PRESS_HOME_RECENT_SYSTEM_UI) {
+                toggleRecentApps();
+            } else if (mLongPressOnHomeBehavior == LONG_PRESS_HOME_ASSIST) {
+                launchAssistAction();
             }
         }
     }
 
+    private void handleDoubleTapOnHome() {
+        if (mDoubleTapOnHomeBehavior == DOUBLE_TAP_HOME_RECENT_SYSTEM_UI) {
+            mHomeConsumed = true;
+            toggleRecentApps();
+        }
+    }
+
+    private final Runnable mHomeDoubleTapTimeoutRunnable = new Runnable() {
+        @Override
+        public void run() {
+            if (mHomeDoubleTapPending) {
+                mHomeDoubleTapPending = false;
+                launchHomeFromHotKey();
+            }
+        }
+    };
+
     /**
      * Create (if necessary) and show or dismiss the recent apps dialog according
      * according to the requested behavior.
@@ -877,6 +885,21 @@ public class PhoneWindowManager implements WindowManagerPolicy {
                 com.android.internal.R.integer.config_lidNavigationAccessibility);
         mLidControlsSleep = mContext.getResources().getBoolean(
                 com.android.internal.R.bool.config_lidControlsSleep);
+
+        mLongPressOnHomeBehavior = mContext.getResources().getInteger(
+                com.android.internal.R.integer.config_longPressOnHomeBehavior);
+        if (mLongPressOnHomeBehavior < LONG_PRESS_HOME_NOTHING ||
+                mLongPressOnHomeBehavior > LONG_PRESS_HOME_ASSIST) {
+            mLongPressOnHomeBehavior = LONG_PRESS_HOME_NOTHING;
+        }
+
+        mDoubleTapOnHomeBehavior = mContext.getResources().getInteger(
+                com.android.internal.R.integer.config_doubleTapOnHomeBehavior);
+        if (mDoubleTapOnHomeBehavior < DOUBLE_TAP_HOME_NOTHING ||
+                mDoubleTapOnHomeBehavior > DOUBLE_TAP_HOME_RECENT_SYSTEM_UI) {
+            mDoubleTapOnHomeBehavior = LONG_PRESS_HOME_NOTHING;
+        }
+
         // register for dock events
         IntentFilter filter = new IntentFilter();
         filter.addAction(UiModeManager.ACTION_ENTER_CAR_MODE);
@@ -1902,48 +1925,44 @@ public class PhoneWindowManager implements WindowManagerPolicy {
             // If we have released the home key, and didn't do anything else
             // while it was pressed, then it is time to go home!
             if (!down) {
-                final boolean homeWasLongPressed = mHomeLongPressed;
+                cancelPreloadRecentApps();
+
                 mHomePressed = false;
-                mHomeLongPressed = false;
-                if (!homeWasLongPressed) {
-                    if (mLongPressOnHomeBehavior != LONG_PRESS_HOME_NOTHING) {
-                        try {
-                            IStatusBarService statusbar = getStatusBarService();
-                            if (statusbar != null) {
-                                statusbar.cancelPreloadRecentApps();
-                            }
-                        } catch (RemoteException e) {
-                            Slog.e(TAG, "RemoteException when showing recent apps", e);
-                            // re-acquire status bar service next time it is needed.
-                            mStatusBarService = null;
-                        }
-                    }
+                if (mHomeConsumed) {
+                    mHomeConsumed = false;
+                    return -1;
+                }
 
-                    mHomePressed = false;
-                    if (!canceled) {
-                        // If an incoming call is ringing, HOME is totally disabled.
-                        // (The user is already on the InCallScreen at this point,
-                        // and his ONLY options are to answer or reject the call.)
-                        boolean incomingRinging = false;
-                        try {
-                            ITelephony telephonyService = getTelephonyService();
-                            if (telephonyService != null) {
-                                incomingRinging = telephonyService.isRinging();
-                            }
-                        } catch (RemoteException ex) {
-                            Log.w(TAG, "RemoteException from getPhoneInterface()", ex);
-                        }
+                if (canceled) {
+                    Log.i(TAG, "Ignoring HOME; event canceled.");
+                    return -1;
+                }
 
-                        if (incomingRinging) {
-                            Log.i(TAG, "Ignoring HOME; there's a ringing incoming call.");
-                        } else {
-                            launchHomeFromHotKey();
-                        }
-                    } else {
-                        Log.i(TAG, "Ignoring HOME; event canceled.");
+                // If an incoming call is ringing, HOME is totally disabled.
+                // (The user is already on the InCallScreen at this point,
+                // and his ONLY options are to answer or reject the call.)
+                try {
+                    ITelephony telephonyService = getTelephonyService();
+                    if (telephonyService != null && telephonyService.isRinging()) {
+                        Log.i(TAG, "Ignoring HOME; there's a ringing incoming call.");
+                        return -1;
                     }
+                } catch (RemoteException ex) {
+                    Log.w(TAG, "RemoteException from getPhoneInterface()", ex);
+                }
+
+                // Delay handling home if a double-tap is possible.
+                if (mDoubleTapOnHomeBehavior != DOUBLE_TAP_HOME_NOTHING) {
+                    mHandler.removeCallbacks(mHomeDoubleTapTimeoutRunnable); // just in case
+                    mHomeDoubleTapPending = true;
+                    mHandler.postDelayed(mHomeDoubleTapTimeoutRunnable,
+                            ViewConfiguration.getDoubleTapTimeout());
                     return -1;
                 }
+
+                // Go home!
+                launchHomeFromHotKey();
+                return -1;
             }
 
             // If a system window has focus, then it doesn't make sense
@@ -1964,25 +1983,21 @@ public class PhoneWindowManager implements WindowManagerPolicy {
                     }
                 }
             }
-            if (down) {
-                if (!mHomePressed && mLongPressOnHomeBehavior == LONG_PRESS_HOME_RECENT_SYSTEM_UI) {
-                    try {
-                        IStatusBarService statusbar = getStatusBarService();
-                        if (statusbar != null) {
-                            statusbar.preloadRecentApps();
-                        }
-                    } catch (RemoteException e) {
-                        Slog.e(TAG, "RemoteException when preloading recent apps", e);
-                        // re-acquire status bar service next time it is needed.
-                        mStatusBarService = null;
-                    }
+
+            // Remember that home is pressed and handle special actions.
+            if (repeatCount == 0) {
+                mHomePressed = true;
+                if (mHomeDoubleTapPending) {
+                    mHomeDoubleTapPending = false;
+                    mHandler.removeCallbacks(mHomeDoubleTapTimeoutRunnable);
+                    handleDoubleTapOnHome();
+                } else if (mLongPressOnHomeBehavior == LONG_PRESS_HOME_RECENT_SYSTEM_UI
+                        || mDoubleTapOnHomeBehavior == DOUBLE_TAP_HOME_RECENT_SYSTEM_UI) {
+                    preloadRecentApps();
                 }
-                if (repeatCount == 0) {
-                    mHomePressed = true;
-                } else if ((event.getFlags() & KeyEvent.FLAG_LONG_PRESS) != 0) {
-                    if (!keyguardOn) {
-                        handleLongPressOnHome();
-                    }
+            } else if ((event.getFlags() & KeyEvent.FLAG_LONG_PRESS) != 0) {
+                if (!keyguardOn) {
+                    handleLongPressOnHome();
                 }
             }
             return -1;
@@ -2029,19 +2044,10 @@ public class PhoneWindowManager implements WindowManagerPolicy {
             return 0;
         } else if (keyCode == KeyEvent.KEYCODE_APP_SWITCH) {
             if (!keyguardOn) {
-                try {
-                    IStatusBarService statusbar = getStatusBarService();
-                    if (statusbar != null) {
-                        if (down && repeatCount == 0) {
-                            statusbar.preloadRecentApps();
-                        } else if (!down) {
-                            statusbar.toggleRecentApps();
-                        }
-                    }
-                } catch (RemoteException e) {
-                    Slog.e(TAG, "RemoteException when preloading recent apps", e);
-                    // re-acquire status bar service next time it is needed.
-                    mStatusBarService = null;
+                if (down && repeatCount == 0) {
+                    preloadRecentApps();
+                } else if (!down) {
+                    toggleRecentApps();
                 }
             }
             return -1;
@@ -2307,6 +2313,51 @@ public class PhoneWindowManager implements WindowManagerPolicy {
         return mSearchManager;
     }
 
+    private void preloadRecentApps() {
+        mPreloadedRecentApps = true;
+        try {
+            IStatusBarService statusbar = getStatusBarService();
+            if (statusbar != null) {
+                statusbar.preloadRecentApps();
+            }
+        } catch (RemoteException e) {
+            Slog.e(TAG, "RemoteException when preloading recent apps", e);
+            // re-acquire status bar service next time it is needed.
+            mStatusBarService = null;
+        }
+    }
+
+    private void cancelPreloadRecentApps() {
+        if (mPreloadedRecentApps) {
+            mPreloadedRecentApps = false;
+            try {
+                IStatusBarService statusbar = getStatusBarService();
+                if (statusbar != null) {
+                    statusbar.cancelPreloadRecentApps();
+                }
+            } catch (RemoteException e) {
+                Slog.e(TAG, "RemoteException when showing recent apps", e);
+                // re-acquire status bar service next time it is needed.
+                mStatusBarService = null;
+            }
+        }
+    }
+
+    private void toggleRecentApps() {
+        mPreloadedRecentApps = false; // preloading no longer needs to be canceled
+        sendCloseSystemWindows(SYSTEM_DIALOG_REASON_RECENT_APPS);
+        try {
+            IStatusBarService statusbar = getStatusBarService();
+            if (statusbar != null) {
+                statusbar.toggleRecentApps();
+            }
+        } catch (RemoteException e) {
+            Slog.e(TAG, "RemoteException when showing recent apps", e);
+            // re-acquire status bar service next time it is needed.
+            mStatusBarService = null;
+        }
+    }
+
     /**
      * A home key -> launch home action was detected.  Take the appropriate action
      * given the situation with the keyguard.