SystemUI: make long pressing recent switch to last app

With this patch, long pressing the recents key on the navigation bar
will attempt to switch to your last application in the activity stack
before the active one.

The user's current home launcher package is ignored as well as SystemUI (so that
RecentsActivity does not influence the behavior).

Change-Id: I38771e0fce16b55bb5186af47115b4e812cb60b0
Signed-off-by: Roman Birg <roman@cyngn.com>
Signed-off-by: Adnan Begovic <adnan@cyngn.com>

packages/SystemUI/res/anim/last_app_in.xml

@@ -0,0 +1,37 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Copyright (C) 2014 The CyanogenMod 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.
+-->
+
+<set xmlns:android="http://schemas.android.com/apk/res/android"
+    android:interpolator="@android:interpolator/linear">
+
+    <translate android:fromXDelta="0%" android:toXDelta="-35%"
+        android:zAdjustment="bottom"
+        android:duration="@android:integer/config_shortAnimTime"
+        />
+    <scale android:fromXScale="0.80" android:toXScale="1.0"
+        android:fromYScale="0.80" android:toYScale="1.0"
+        android:pivotX="50%" android:pivotY="50%"
+        android:duration="@android:integer/config_shortAnimTime"
+        />
+    <translate android:fromXDelta="-35%" android:toXDelta="35%"
+        android:zAdjustment="top"
+        android:startOffset="@android:integer/config_shortAnimTime"
+        android:duration="@android:integer/config_shortAnimTime"
+        />
+    <alpha android:fromAlpha="0.6" android:toAlpha="1.0"
+        android:duration="@android:integer/config_shortAnimTime"
+        />
+</set>

packages/SystemUI/res/anim/last_app_out.xml

@@ -0,0 +1,37 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Copyright (C) 2014 The CyanogenMod 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.
+-->
+
+<set xmlns:android="http://schemas.android.com/apk/res/android"
+    android:interpolator="@android:interpolator/linear">
+
+    <translate android:fromXDelta="-35%" android:toXDelta="35%"
+        android:zAdjustment="top"
+        android:duration="@android:integer/config_shortAnimTime"
+        />
+    <scale android:fromXScale="1.0" android:toXScale="0.80"
+        android:fromYScale="1.0" android:toYScale="0.80"
+        android:pivotX="50%" android:pivotY="50%"
+        android:duration="@android:integer/config_shortAnimTime"
+        />
+    <translate android:fromXDelta="35%" android:toXDelta="-35%"
+        android:zAdjustment="bottom"
+        android:startOffset="@android:integer/config_shortAnimTime"
+        android:duration="@android:integer/config_shortAnimTime"
+        />
+    <alpha android:fromAlpha="1.0" android:toAlpha="0.6"
+        android:duration="@android:integer/config_shortAnimTime"
+        />
+</set>

packages/SystemUI/src/com/android/systemui/statusbar/phone/PhoneStatusBar.java

@@ -38,6 +38,7 @@
 import android.annotation.NonNull;
 import android.app.ActivityManager;
 import android.app.ActivityManagerNative;
+import android.app.ActivityOptions;
 import android.app.IActivityManager;
 import android.app.Notification;
 import android.app.PendingIntent;
@@ -47,6 +48,8 @@
 import android.content.Context;
 import android.content.Intent;
 import android.content.IntentFilter;
+import android.content.pm.PackageManager;
+import android.content.pm.ResolveInfo;
 import android.content.res.Configuration;
 import android.content.res.Resources;
 import android.database.ContentObserver;
@@ -4305,6 +4308,7 @@ public void onScreenTurnedOn() {
     private void handleLongPressBackRecents(View v) {
         try {
             boolean sendBackLongPress = false;
+            boolean hijackRecentsLongPress = false;
             IActivityManager activityManager = ActivityManagerNative.getDefault();
             boolean isAccessiblityEnabled = mAccessibilityManager.isEnabled();
             if (activityManager.isInLockTaskMode() && !isAccessiblityEnabled) {
@@ -4318,12 +4322,16 @@ private void handleLongPressBackRecents(View v) {
                     // If we aren't pressing recents right now then they presses
                     // won't be together, so send the standard long-press action.
                     sendBackLongPress = true;
+                } else if ((v.getId() == R.id.recent_apps)) {
+                    hijackRecentsLongPress = true;
                 }
                 mLastLockToAppLongPress = time;
             } else {
                 // If this is back still need to handle sending the long-press event.
                 if (v.getId() == R.id.back) {
                     sendBackLongPress = true;
+                } else if (v.getId() == R.id.recent_apps) {
+                    hijackRecentsLongPress = true;
                 } else if (isAccessiblityEnabled && activityManager.isInLockTaskMode()) {
                     // When in accessibility mode a long press that is recents (not back)
                     // should stop lock task.
@@ -4335,11 +4343,48 @@ private void handleLongPressBackRecents(View v) {
                 keyButtonView.sendEvent(KeyEvent.ACTION_DOWN, KeyEvent.FLAG_LONG_PRESS);
                 keyButtonView.sendAccessibilityEvent(AccessibilityEvent.TYPE_VIEW_LONG_CLICKED);
             }
+
+            if (hijackRecentsLongPress) {
+                final ActivityManager am =
+                        (ActivityManager) mContext.getSystemService(Context.ACTIVITY_SERVICE);
+                ActivityManager.RunningTaskInfo lastTask = getLastTask(am);
+
+                if (lastTask != null) {
+                    if (DEBUG) Log.d(TAG, "switching to " + lastTask.topActivity.getPackageName());
+                    final ActivityOptions opts = ActivityOptions.makeCustomAnimation(mContext,
+                            R.anim.last_app_in, R.anim.last_app_out);
+                    am.moveTaskToFront(lastTask.id, ActivityManager.MOVE_TASK_NO_USER_ACTION,
+                            opts.toBundle());
+                }
+            }
         } catch (RemoteException e) {
             Log.d(TAG, "Unable to reach activity manager", e);
         }
     }
 
+    private ActivityManager.RunningTaskInfo getLastTask(final ActivityManager am) {
+        final String defaultHomePackage = resolveCurrentLauncherPackage();
+        List<ActivityManager.RunningTaskInfo> tasks = am.getRunningTasks(5);
+
+        for (int i = 1; i < tasks.size(); i++) {
+            String packageName = tasks.get(i).topActivity.getPackageName();
+            if (!packageName.equals(defaultHomePackage)
+                    && !packageName.equals(mContext.getPackageName())) {
+                return tasks.get(i);
+            }
+        }
+
+        return null;
+    }
+
+    private String resolveCurrentLauncherPackage() {
+        final Intent launcherIntent = new Intent(Intent.ACTION_MAIN)
+                .addCategory(Intent.CATEGORY_HOME);
+        final PackageManager pm = mContext.getPackageManager();
+        final ResolveInfo launcherInfo = pm.resolveActivity(launcherIntent, 0);
+        return launcherInfo.activityInfo.packageName;
+    }
+
     // Recents
 
     @Override

packages/SystemUI/src/com/android/systemui/statusbar/policy/KeyButtonView.java

@@ -73,13 +73,15 @@ public class KeyButtonView extends ImageView {
     private Animator mAnimateToQuiescent = new ObjectAnimator();
 
     private PowerManager mPm;
+    private boolean mPerformedLongClick;
 
     private final Runnable mCheckLongPress = new Runnable() {
         public void run() {
             if (isPressed()) {
                 // Log.d("KeyButtonView", "longpressed: " + this);
                 if (isLongClickable()) {
                     // Just an old-fashioned ImageView
+                    mPerformedLongClick = true;
                     performLongClick();
                 } else {
                     sendEvent(KeyEvent.ACTION_DOWN, KeyEvent.FLAG_LONG_PRESS);
@@ -228,13 +230,14 @@ && x < getWidth() + mTouchSlop
                     }
                 } else {
                     // no key code, just a regular ImageView
-                    if (doIt) {
+                    if (doIt && !mPerformedLongClick) {
                         performClick();
                     }
                 }
                 if (mSupportsLongpress) {
                     removeCallbacks(mCheckLongPress);
                 }
+                mPerformedLongClick = false;
                 break;
         }