1 /* 2 * Copyright (C) 2006 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; 18 19 import android.content.res.Configuration; 20 21 /** 22 * The set of callback APIs that are common to all application components 23 * ({@link android.app.Activity}, {@link android.app.Service}, 24 * {@link ContentProvider}, and {@link android.app.Application}). 25 */ 26 public interface ComponentCallbacks { 27 /** 28 * Called by the system when the device configuration changes while your 29 * component is running. Note that, unlike activities, other components 30 * are never restarted when a configuration changes: they must always deal 31 * with the results of the change, such as by re-retrieving resources. 32 * 33 * <p>At the time that this function has been called, your Resources 34 * object will have been updated to return resource values matching the 35 * new configuration. 36 * 37 * @param newConfig The new device configuration. 38 */ onConfigurationChanged(Configuration newConfig)39 void onConfigurationChanged(Configuration newConfig); 40 41 /** 42 * This is called when the overall system is running low on memory, and 43 * would like actively running process to try to tighten their belt. While 44 * the exact point at which this will be called is not defined, generally 45 * it will happen around the time all background process have been killed, 46 * that is before reaching the point of killing processes hosting 47 * service and foreground UI that we would like to avoid killing. 48 * 49 * <p>Applications that want to be nice can implement this method to release 50 * any caches or other unnecessary resources they may be holding on to. 51 * The system will perform a gc for you after returning from this method. 52 */ onLowMemory()53 void onLowMemory(); 54 } 55