1 /*
2  * Copyright (C) 2022 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.windowdecor;
18 
19 import android.app.ActivityManager;
20 import android.os.IBinder;
21 import android.view.SurfaceControl;
22 import android.window.TransitionInfo;
23 
24 import com.android.wm.shell.freeform.FreeformTaskTransitionStarter;
25 import com.android.wm.shell.splitscreen.SplitScreenController;
26 
27 /**
28  * The interface used by some {@link com.android.wm.shell.ShellTaskOrganizer.TaskListener} to help
29  * customize {@link WindowDecoration}. Its implementations are responsible to interpret user's
30  * interactions with UI widgets in window decorations and send corresponding requests to system
31  * servers.
32  */
33 public interface WindowDecorViewModel {
34     /**
35      * Sets the transition starter that starts freeform task transitions. Only called when
36      * {@link com.android.wm.shell.transition.Transitions#ENABLE_SHELL_TRANSITIONS} is {@code true}.
37      *
38      * @param transitionStarter the transition starter that starts freeform task transitions
39      */
setFreeformTaskTransitionStarter(FreeformTaskTransitionStarter transitionStarter)40     void setFreeformTaskTransitionStarter(FreeformTaskTransitionStarter transitionStarter);
41 
42     /**
43      * Sets the {@link SplitScreenController} if available.
44      */
setSplitScreenController(SplitScreenController splitScreenController)45     void setSplitScreenController(SplitScreenController splitScreenController);
46 
47     /**
48      * Creates a window decoration for the given task. Can be {@code null} for Fullscreen tasks but
49      * not Freeform ones.
50      *
51      * @param taskInfo    the initial task info of the task
52      * @param taskSurface the surface of the task
53      * @param startT      the start transaction to be applied before the transition
54      * @param finishT     the finish transaction to restore states after the transition
55      * @return {@code true} if window decoration was created, {@code false} otherwise
56      */
onTaskOpening( ActivityManager.RunningTaskInfo taskInfo, SurfaceControl taskSurface, SurfaceControl.Transaction startT, SurfaceControl.Transaction finishT)57     boolean onTaskOpening(
58             ActivityManager.RunningTaskInfo taskInfo,
59             SurfaceControl taskSurface,
60             SurfaceControl.Transaction startT,
61             SurfaceControl.Transaction finishT);
62 
63     /**
64      * Notifies a task info update on the given task, with the window decoration created previously
65      * for this task by {@link #onTaskOpening}.
66      *
67      * @param taskInfo the new task info of the task
68      */
onTaskInfoChanged(ActivityManager.RunningTaskInfo taskInfo)69     void onTaskInfoChanged(ActivityManager.RunningTaskInfo taskInfo);
70 
71     /**
72      * Notifies a transition is about to start about the given task to give the window decoration a
73      * chance to prepare for this transition. Unlike {@link #onTaskInfoChanged}, this method creates
74      * a window decoration if one does not exist but is required.
75      *
76      * @param taskInfo    the initial task info of the task
77      * @param taskSurface the surface of the task
78      * @param startT      the start transaction to be applied before the transition
79      * @param finishT     the finish transaction to restore states after the transition
80      */
onTaskChanging( ActivityManager.RunningTaskInfo taskInfo, SurfaceControl taskSurface, SurfaceControl.Transaction startT, SurfaceControl.Transaction finishT)81     void onTaskChanging(
82             ActivityManager.RunningTaskInfo taskInfo,
83             SurfaceControl taskSurface,
84             SurfaceControl.Transaction startT,
85             SurfaceControl.Transaction finishT);
86 
87     /**
88      * Notifies that the given task is about to close to give the window decoration a chance to
89      * prepare for this transition.
90      *
91      * @param taskInfo the initial task info of the task
92      * @param startT   the start transaction to be applied before the transition
93      * @param finishT  the finish transaction to restore states after the transition
94      */
onTaskClosing( ActivityManager.RunningTaskInfo taskInfo, SurfaceControl.Transaction startT, SurfaceControl.Transaction finishT)95     void onTaskClosing(
96             ActivityManager.RunningTaskInfo taskInfo,
97             SurfaceControl.Transaction startT,
98             SurfaceControl.Transaction finishT);
99 
100     /**
101      * Destroys the window decoration of the give task.
102      *
103      * @param taskInfo the info of the task
104      */
destroyWindowDecoration(ActivityManager.RunningTaskInfo taskInfo)105     void destroyWindowDecoration(ActivityManager.RunningTaskInfo taskInfo);
106 
107     /**
108      * Notifies that a shell transition is about to start. If the transition is of type
109      * TRANSIT_ENTER_DESKTOP, it will save that transition to unpause relayout for the transitioning
110      * task after the transition has ended.
111      *
112      * @param transition the ready transaction
113      * @param info of Transition to check if relayout needs to be paused for a task
114      * @param change a change in the given transition
115      */
onTransitionReady(IBinder transition, TransitionInfo info, TransitionInfo.Change change)116     default void onTransitionReady(IBinder transition, TransitionInfo info,
117             TransitionInfo.Change change) {}
118 
119     /**
120      * Notifies that a shell transition is about to merge with another to give the window
121      * decoration a chance to prepare for this merge.
122      *
123      * @param merged the transaction being merged
124      * @param playing the transaction being merged into
125      */
onTransitionMerged(IBinder merged, IBinder playing)126     default void onTransitionMerged(IBinder merged, IBinder playing) {}
127 
128     /**
129      * Notifies that a shell transition is about to finish  to give the window decoration a chance
130      * to clean up.
131      *
132      * @param transaction
133      */
onTransitionFinished(IBinder transaction)134     default void onTransitionFinished(IBinder transaction) {}
135 
136 }