1 /*
2  * Copyright (C) 2023 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 package com.android.wm.shell.transition;
18 
19 import static android.app.WindowConfiguration.ACTIVITY_TYPE_HOME;
20 import static android.view.Display.DEFAULT_DISPLAY;
21 import static android.window.TransitionInfo.FLAG_BACK_GESTURE_ANIMATED;
22 
23 import static com.android.wm.shell.transition.Transitions.TRANSIT_DESKTOP_MODE_START_DRAG_TO_DESKTOP;
24 import static com.android.wm.shell.transition.Transitions.TransitionObserver;
25 
26 import android.annotation.NonNull;
27 import android.app.ActivityManager;
28 import android.content.Context;
29 import android.os.IBinder;
30 import android.view.SurfaceControl;
31 import android.window.TransitionInfo;
32 
33 import com.android.wm.shell.common.RemoteCallable;
34 import com.android.wm.shell.common.ShellExecutor;
35 import com.android.wm.shell.common.SingleInstanceRemoteListener;
36 import com.android.wm.shell.shared.IHomeTransitionListener;
37 import com.android.wm.shell.shared.TransitionUtil;
38 
39 /**
40  * The {@link TransitionObserver} that observes for transitions involving the home
41  * activity on the {@link android.view.Display#DEFAULT_DISPLAY} only.
42  * It reports transitions to the caller via {@link IHomeTransitionListener}.
43  */
44 public class HomeTransitionObserver implements TransitionObserver,
45         RemoteCallable<HomeTransitionObserver> {
46     private SingleInstanceRemoteListener<HomeTransitionObserver, IHomeTransitionListener>
47             mListener;
48 
49     private @NonNull final Context mContext;
50     private @NonNull final ShellExecutor mMainExecutor;
HomeTransitionObserver(@onNull Context context, @NonNull ShellExecutor mainExecutor)51     public HomeTransitionObserver(@NonNull Context context,
52             @NonNull ShellExecutor mainExecutor) {
53         mContext = context;
54         mMainExecutor = mainExecutor;
55     }
56 
57     @Override
onTransitionReady(@onNull IBinder transition, @NonNull TransitionInfo info, @NonNull SurfaceControl.Transaction startTransaction, @NonNull SurfaceControl.Transaction finishTransaction)58     public void onTransitionReady(@NonNull IBinder transition,
59             @NonNull TransitionInfo info,
60             @NonNull SurfaceControl.Transaction startTransaction,
61             @NonNull SurfaceControl.Transaction finishTransaction) {
62         for (TransitionInfo.Change change : info.getChanges()) {
63             final ActivityManager.RunningTaskInfo taskInfo = change.getTaskInfo();
64             if (info.getType() == TRANSIT_DESKTOP_MODE_START_DRAG_TO_DESKTOP
65                     || taskInfo == null
66                     || taskInfo.displayId != DEFAULT_DISPLAY
67                     || taskInfo.taskId == -1
68                     || !taskInfo.isRunning) {
69                 continue;
70             }
71 
72             final int mode = change.getMode();
73             final boolean isBackGesture = change.hasFlags(FLAG_BACK_GESTURE_ANIMATED);
74             if (taskInfo.getActivityType() == ACTIVITY_TYPE_HOME
75                     && (TransitionUtil.isOpenOrCloseMode(mode) || isBackGesture)) {
76                 notifyHomeVisibilityChanged(TransitionUtil.isOpeningType(mode) || isBackGesture);
77             }
78         }
79     }
80 
81     @Override
onTransitionStarting(@onNull IBinder transition)82     public void onTransitionStarting(@NonNull IBinder transition) {}
83 
84     @Override
onTransitionMerged(@onNull IBinder merged, @NonNull IBinder playing)85     public void onTransitionMerged(@NonNull IBinder merged,
86             @NonNull IBinder playing) {}
87 
88     @Override
onTransitionFinished(@onNull IBinder transition, boolean aborted)89     public void onTransitionFinished(@NonNull IBinder transition,
90             boolean aborted) {}
91 
92     /**
93      * Sets the home transition listener that receives any transitions resulting in a change of
94      *
95      */
setHomeTransitionListener(Transitions transitions, IHomeTransitionListener listener)96     public void setHomeTransitionListener(Transitions transitions,
97             IHomeTransitionListener listener) {
98         if (mListener == null) {
99             mListener = new SingleInstanceRemoteListener<>(this,
100                     c -> transitions.registerObserver(this),
101                     c -> transitions.unregisterObserver(this));
102         }
103 
104         if (listener != null) {
105             mListener.register(listener);
106         } else {
107             mListener.unregister();
108         }
109     }
110 
111     /**
112      * Notifies the listener that the home visibility has changed.
113      * @param isVisible true when home activity is visible, false otherwise.
114      */
notifyHomeVisibilityChanged(boolean isVisible)115     public void notifyHomeVisibilityChanged(boolean isVisible) {
116         if (mListener != null) {
117             mListener.call(l -> l.onHomeVisibilityChanged(isVisible));
118         }
119     }
120 
121     @Override
getContext()122     public Context getContext() {
123         return mContext;
124     }
125 
126     @Override
getRemoteCallExecutor()127     public ShellExecutor getRemoteCallExecutor() {
128         return mMainExecutor;
129     }
130 
131     /**
132      * Invalidates this controller, preventing future calls to send updates.
133      */
invalidate(Transitions transitions)134     public void invalidate(Transitions transitions) {
135         transitions.unregisterObserver(this);
136         if (mListener != null) {
137             // Unregister the listener to ensure any registered binder death recipients are unlinked
138             mListener.unregister();
139         }
140     }
141 }
142