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.graphics.drawable.Drawable; 20 21 /** 22 * Class which can be used to cache Drawable resources against a theme. 23 */ 24 class DrawableCache extends ThemedResourceCache<Drawable.ConstantState> { 25 private final Resources mResources; 26 27 /** 28 * Creates a cache for the given Resources instance. 29 * 30 * @param resources the resources to use when creating new instances 31 */ 32 public DrawableCache(Resources resources) { 33 mResources = resources; 34 } 35 36 /** 37 * If the resource is cached, creates and returns a new instance of it. 38 * 39 * @param key a key that uniquely identifies the drawable resource 40 * @param theme the theme where the resource will be used 41 * @return a new instance of the resource, or {@code null} if not in 42 * the cache 43 */ 44 public Drawable getInstance(long key, Resources.Theme theme) { 45 final Drawable.ConstantState entry = get(key, theme); 46 if (entry != null) { 47 return entry.newDrawable(mResources, theme); 48 } 49 50 return null; 51 } 52 53 @Override 54 public boolean shouldInvalidateEntry(Drawable.ConstantState entry, int configChanges) { 55 return Configuration.needNewResources(configChanges, entry.getChangingConfigurations()); 56 } 57 } 58
