1 /* 2 * Copyright (C) 2014 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.content.pm.ActivityInfo.Config; 21 22 /** 23 * A Cache class which can be used to cache resource objects that are easy to clone but more 24 * expensive to inflate. 25 * 26 * @hide For internal use only. 27 */ 28 public class ConfigurationBoundResourceCache<T> extends ThemedResourceCache<ConstantState<T>> { 29 30 @UnsupportedAppUsage ConfigurationBoundResourceCache()31 public ConfigurationBoundResourceCache() { 32 } 33 34 /** 35 * If the resource is cached, creates and returns a new instance of it. 36 * 37 * @param key a key that uniquely identifies the drawable resource 38 * @param resources a Resources object from which to create new instances. 39 * @param theme the theme where the resource will be used 40 * @return a new instance of the resource, or {@code null} if not in 41 * the cache 42 */ getInstance(long key, Resources resources, Resources.Theme theme)43 public T getInstance(long key, Resources resources, Resources.Theme theme) { 44 final ConstantState<T> entry = get(key, theme); 45 if (entry != null) { 46 return entry.newInstance(resources, theme); 47 } 48 49 return null; 50 } 51 52 @Override shouldInvalidateEntry(ConstantState<T> entry, @Config int configChanges)53 public boolean shouldInvalidateEntry(ConstantState<T> entry, @Config int configChanges) { 54 return Configuration.needNewResources(configChanges, entry.getChangingConfigurations()); 55 } 56 } 57