1 /*
2  * Copyright (C) 2021 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 androidx.window.extensions;
18 
19 import android.app.ActivityThread;
20 import android.content.Context;
21 
22 import androidx.annotation.NonNull;
23 import androidx.window.extensions.embedding.ActivityEmbeddingComponent;
24 import androidx.window.extensions.embedding.SplitController;
25 import androidx.window.extensions.layout.WindowLayoutComponent;
26 import androidx.window.extensions.layout.WindowLayoutComponentImpl;
27 
28 /**
29  * The reference implementation of {@link WindowExtensions} that implements the initial API version.
30  */
31 public class WindowExtensionsImpl implements WindowExtensions {
32 
33     private final Object mLock = new Object();
34     private volatile WindowLayoutComponent mWindowLayoutComponent;
35     private volatile SplitController mSplitController;
36 
37     @Override
getVendorApiLevel()38     public int getVendorApiLevel() {
39         return 1;
40     }
41 
42     /**
43      * Returns a reference implementation of {@link WindowLayoutComponent} if available,
44      * {@code null} otherwise. The implementation must match the API level reported in
45      * {@link WindowExtensions#getWindowLayoutComponent()}.
46      * @return {@link WindowLayoutComponent} OEM implementation
47      */
48     @Override
getWindowLayoutComponent()49     public WindowLayoutComponent getWindowLayoutComponent() {
50         if (mWindowLayoutComponent == null) {
51             synchronized (mLock) {
52                 if (mWindowLayoutComponent == null) {
53                     Context context = ActivityThread.currentApplication();
54                     mWindowLayoutComponent = new WindowLayoutComponentImpl(context);
55                 }
56             }
57         }
58         return mWindowLayoutComponent;
59     }
60 
61     /**
62      * Returns a reference implementation of {@link ActivityEmbeddingComponent} if available,
63      * {@code null} otherwise. The implementation must match the API level reported in
64      * {@link WindowExtensions#getWindowLayoutComponent()}.
65      * @return {@link ActivityEmbeddingComponent} OEM implementation.
66      */
67     @NonNull
getActivityEmbeddingComponent()68     public ActivityEmbeddingComponent getActivityEmbeddingComponent() {
69         if (mSplitController == null) {
70             synchronized (mLock) {
71                 if (mSplitController == null) {
72                     mSplitController = new SplitController();
73                 }
74             }
75         }
76         return mSplitController;
77     }
78 }
79