1/*
2 * Copyright (C) 2018 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 */
16package com.android.quickstep;
17
18import android.annotation.TargetApi;
19import android.content.Context;
20import android.content.Intent;
21import android.os.Build;
22import android.os.Bundle;
23import android.os.Handler;
24
25import com.android.launcher3.MainThreadExecutor;
26import com.android.quickstep.ActivityControlHelper.ActivityInitListener;
27import com.android.quickstep.util.RemoteAnimationProvider;
28
29import java.lang.ref.WeakReference;
30import java.util.function.BiPredicate;
31
32/**
33 * Utility class to track create/destroy for RecentsActivity
34 */
35@TargetApi(Build.VERSION_CODES.P)
36public class RecentsActivityTracker implements ActivityInitListener {
37
38    private static WeakReference<RecentsActivity> sCurrentActivity = new WeakReference<>(null);
39    private static final Scheduler sScheduler = new Scheduler();
40
41    private final BiPredicate<RecentsActivity, Boolean> mOnInitListener;
42
43    public RecentsActivityTracker(BiPredicate<RecentsActivity, Boolean> onInitListener) {
44        mOnInitListener = onInitListener;
45    }
46
47    @Override
48    public void register() {
49        sScheduler.schedule(this);
50    }
51
52    @Override
53    public void unregister() {
54        sScheduler.clearReference(this);
55    }
56
57    private boolean init(RecentsActivity activity, boolean visible) {
58        return mOnInitListener.test(activity, visible);
59    }
60
61    public static RecentsActivity getCurrentActivity() {
62        return sCurrentActivity.get();
63    }
64
65    @Override
66    public void registerAndStartActivity(Intent intent, RemoteAnimationProvider animProvider,
67            Context context, Handler handler, long duration) {
68        register();
69
70        Bundle options = animProvider.toActivityOptions(handler, duration).toBundle();
71        context.startActivity(intent, options);
72    }
73
74    public static void onRecentsActivityCreate(RecentsActivity activity) {
75        sCurrentActivity = new WeakReference<>(activity);
76        sScheduler.initIfPending(activity, false);
77    }
78
79
80    public static void onRecentsActivityNewIntent(RecentsActivity activity) {
81        sScheduler.initIfPending(activity, activity.isStarted());
82    }
83
84    public static void onRecentsActivityDestroy(RecentsActivity activity) {
85        if (sCurrentActivity.get() == activity) {
86            sCurrentActivity.clear();
87        }
88    }
89
90
91    private static class Scheduler implements Runnable {
92
93        private WeakReference<RecentsActivityTracker> mPendingTracker = new WeakReference<>(null);
94        private MainThreadExecutor mMainThreadExecutor;
95
96        public synchronized void schedule(RecentsActivityTracker tracker) {
97            mPendingTracker = new WeakReference<>(tracker);
98            if (mMainThreadExecutor == null) {
99                mMainThreadExecutor = new MainThreadExecutor();
100            }
101            mMainThreadExecutor.execute(this);
102        }
103
104        @Override
105        public void run() {
106            RecentsActivity activity = sCurrentActivity.get();
107            if (activity != null) {
108                initIfPending(activity, activity.isStarted());
109            }
110        }
111
112        public synchronized boolean initIfPending(RecentsActivity activity, boolean alreadyOnHome) {
113            RecentsActivityTracker tracker = mPendingTracker.get();
114            if (tracker != null) {
115                if (!tracker.init(activity, alreadyOnHome)) {
116                    mPendingTracker.clear();
117                }
118                return true;
119            }
120            return false;
121        }
122
123        public synchronized boolean clearReference(RecentsActivityTracker tracker) {
124            if (mPendingTracker.get() == tracker) {
125                mPendingTracker.clear();
126                return true;
127            }
128            return false;
129        }
130    }
131}
132