Merge "Notify moveTaskToBack to TaskStackListeners."

core/java/android/app/ITaskStackListener.aidl

@@ -214,4 +214,11 @@ oneway interface ITaskStackListener {
      * @param displayId id of the display where activity will rotate
      */
      void onActivityRotation(int displayId);
+
+    /**
+     * Called when a task is moved to the back behind the home stack.
+     *
+     * @param taskInfo info about the task which moved
+     */
+    void onTaskMovedToBack(in ActivityManager.RunningTaskInfo taskInfo);
 }

core/java/android/app/TaskStackListener.java

@@ -17,13 +17,13 @@
 package android.app;
 
 import android.app.ActivityManager.RunningTaskInfo;
-import android.window.TaskSnapshot;
 import android.compat.annotation.UnsupportedAppUsage;
 import android.content.ComponentName;
 import android.os.Binder;
 import android.os.Build;
 import android.os.IBinder;
 import android.os.RemoteException;
+import android.window.TaskSnapshot;
 
 /**
  * Classes interested in observing only a subset of changes using ITaskStackListener can extend
@@ -196,4 +196,8 @@ public abstract class TaskStackListener extends ITaskStackListener.Stub {
     @Override
     public void onActivityRotation(int displayId) {
     }
+
+    @Override
+    public void onTaskMovedToBack(RunningTaskInfo taskInfo) {
+    }
 }

services/core/java/com/android/server/wm/Task.java

@@ -5443,9 +5443,13 @@ class Task extends WindowContainer<WindowContainer> {
                 final Task lastFocusedTask = displayArea.getFocusedRootTask();
                 displayArea.positionChildAt(POSITION_BOTTOM, this, false /*includingParents*/);
                 displayArea.updateLastFocusedRootTask(lastFocusedTask, reason);
+                mAtmService.getTaskChangeNotificationController().notifyTaskMovedToBack(
+                        getTaskInfo());
             }
             if (task != null && task != this) {
                 positionChildAtBottom(task);
+                mAtmService.getTaskChangeNotificationController().notifyTaskMovedToBack(
+                        task.getTaskInfo());
             }
             return;
         }

services/core/java/com/android/server/wm/TaskChangeNotificationController.java

@@ -18,7 +18,6 @@ package com.android.server.wm;
 
 import android.app.ActivityManager;
 import android.app.ActivityManager.RunningTaskInfo;
-import android.window.TaskSnapshot;
 import android.app.ITaskStackListener;
 import android.app.TaskInfo;
 import android.content.ComponentName;
@@ -29,6 +28,7 @@ import android.os.Looper;
 import android.os.Message;
 import android.os.RemoteCallbackList;
 import android.os.RemoteException;
+import android.window.TaskSnapshot;
 
 import com.android.internal.os.SomeArgs;
 
@@ -60,6 +60,7 @@ class TaskChangeNotificationController {
     private static final int NOTIFY_TASK_FOCUS_CHANGED_MSG = 25;
     private static final int NOTIFY_TASK_REQUESTED_ORIENTATION_CHANGED_MSG = 26;
     private static final int NOTIFY_ACTIVITY_ROTATED_MSG = 27;
+    private static final int NOTIFY_TASK_MOVED_TO_BACK_LISTENERS_MSG = 28;
 
     // Delay in notifying task stack change listeners (in millis)
     private static final int NOTIFY_TASK_STACK_CHANGE_LISTENERS_DELAY = 100;
@@ -178,6 +179,10 @@ class TaskChangeNotificationController {
         l.onActivityRotation(m.arg1);
     };
 
+    private final TaskStackConsumer mNotifyTaskMovedToBack = (l, m) -> {
+        l.onTaskMovedToBack((RunningTaskInfo) m.obj);
+    };
+
     @FunctionalInterface
     public interface TaskStackConsumer {
         void accept(ITaskStackListener t, Message m) throws RemoteException;
@@ -269,6 +274,9 @@ class TaskChangeNotificationController {
                 case NOTIFY_ACTIVITY_ROTATED_MSG:
                     forAllRemoteListeners(mNotifyOnActivityRotation, msg);
                     break;
+                case NOTIFY_TASK_MOVED_TO_BACK_LISTENERS_MSG:
+                    forAllRemoteListeners(mNotifyTaskMovedToBack, msg);
+                    break;
             }
             if (msg.obj instanceof SomeArgs) {
                 ((SomeArgs) msg.obj).recycle();
@@ -553,4 +561,13 @@ class TaskChangeNotificationController {
         forAllLocalListeners(mNotifyOnActivityRotation, msg);
         msg.sendToTarget();
     }
+
+    /**
+     * Notify that a task is being moved behind home.
+     */
+    void notifyTaskMovedToBack(TaskInfo ti) {
+        final Message msg = mHandler.obtainMessage(NOTIFY_TASK_MOVED_TO_BACK_LISTENERS_MSG, ti);
+        forAllLocalListeners(mNotifyTaskMovedToBack, msg);
+        msg.sendToTarget();
+    }
 }