1 /*
2  * Copyright (C) 2015 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 android.content.res;
18 
19 import android.compat.annotation.UnsupportedAppUsage;
20 import android.graphics.drawable.Drawable;
21 import android.os.Build;
22 
23 /**
24  * Class which can be used to cache Drawable resources against a theme.
25  */
26 class DrawableCache extends ThemedResourceCache<Drawable.ConstantState> {
27 
28     @UnsupportedAppUsage
DrawableCache()29     DrawableCache() {
30     }
31 
32     /**
33      * If the resource is cached, creates and returns a new instance of it.
34      *
35      * @param key a key that uniquely identifies the drawable resource
36      * @param resources a Resources object from which to create new instances.
37      * @param theme the theme where the resource will be used
38      * @return a new instance of the resource, or {@code null} if not in
39      *         the cache
40      */
41     @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
getInstance(long key, Resources resources, Resources.Theme theme)42     public Drawable getInstance(long key, Resources resources, Resources.Theme theme) {
43         final Drawable.ConstantState entry = get(key, theme);
44         if (entry != null) {
45             return entry.newDrawable(resources, theme);
46         }
47 
48         return null;
49     }
50 
51     @Override
shouldInvalidateEntry(Drawable.ConstantState entry, int configChanges)52     public boolean shouldInvalidateEntry(Drawable.ConstantState entry, int configChanges) {
53         return Configuration.needNewResources(configChanges, entry.getChangingConfigurations());
54     }
55 }
56