/* * Copyright (C) 2006 The Android Open Source Project * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package android.app; import java.util.ArrayList; import android.content.ComponentCallbacks; import android.content.ComponentCallbacks2; import android.content.Context; import android.content.ContextWrapper; import android.content.res.Configuration; import android.os.Bundle; /** * Base class for those who need to maintain global application state. You can * provide your own implementation by specifying its name in your * AndroidManifest.xml's <application> tag, which will cause that class * to be instantiated for you when the process for your application/package is * created. * * <p class="note">There is normally no need to subclass Application. In * most situation, static singletons can provide the same functionality in a * more modular way. If your singleton needs a global context (for example * to register broadcast receivers), the function to retrieve it can be * given a {@link android.content.Context} which internally uses * {@link android.content.Context#getApplicationContext() Context.getApplicationContext()} * when first constructing the singleton.</p> */ public class Application extends ContextWrapper implements ComponentCallbacks2 { private ArrayList<ComponentCallbacks> mComponentCallbacks = new ArrayList<ComponentCallbacks>(); private ArrayList<ActivityLifecycleCallbacks> mActivityLifecycleCallbacks = new ArrayList<ActivityLifecycleCallbacks>(); /** @hide */ public LoadedApk mLoadedApk; public interface ActivityLifecycleCallbacks { void onActivityCreated(Activity activity, Bundle savedInstanceState); void onActivityStarted(Activity activity); void onActivityResumed(Activity activity); void onActivityPaused(Activity activity); void onActivityStopped(Activity activity); void onActivitySaveInstanceState(Activity activity, Bundle outState); void onActivityDestroyed(Activity activity); } public Application() { super(null); } /** * Called when the application is starting, before any activity, service, * or receiver objects (excluding content providers) have been created. * Implementations should be as quick as possible (for example using * lazy initialization of state) since the time spent in this function * directly impacts the performance of starting the first activity, * service, or receiver in a process. * If you override this method, be sure to call super.onCreate(). */ public void onCreate() { } /** * This method is for use in emulated process environments. It will * never be called on a production Android device, where processes are * removed by simply killing them; no user code (including this callback) * is executed when doing so. */ public void onTerminate() { } public void onConfigurationChanged(Configuration newConfig) { Object[] callbacks = collectComponentCallbacks(); if (callbacks != null) { for (int i=0; i<callbacks.length; i++) { ((ComponentCallbacks)callbacks[i]).onConfigurationChanged(newConfig); } } } public void onLowMemory() { Object[] callbacks = collectComponentCallbacks(); if (callbacks != null) { for (int i=0; i<callbacks.length; i++) { ((ComponentCallbacks)callbacks[i]).onLowMemory(); } } } public void onTrimMemory(int level) { Object[] callbacks = collectComponentCallbacks(); if (callbacks != null) { for (int i=0; i<callbacks.length; i++) { Object c = callbacks[i]; if (c instanceof ComponentCallbacks2) { ((ComponentCallbacks2)c).onTrimMemory(level); } } } } public void registerComponentCallbacks(ComponentCallbacks callback) { synchronized (mComponentCallbacks) { mComponentCallbacks.add(callback); } } public void unregisterComponentCallbacks(ComponentCallbacks callback) { synchronized (mComponentCallbacks) { mComponentCallbacks.remove(callback); } } public void registerActivityLifecycleCallbacks(ActivityLifecycleCallbacks callback) { synchronized (mActivityLifecycleCallbacks) { mActivityLifecycleCallbacks.add(callback); } } public void unregisterActivityLifecycleCallbacks(ActivityLifecycleCallbacks callback) { synchronized (mActivityLifecycleCallbacks) { mActivityLifecycleCallbacks.remove(callback); } } // ------------------ Internal API ------------------ /** * @hide */ /* package */ final void attach(Context context) { attachBaseContext(context); mLoadedApk = ContextImpl.getImpl(context).mPackageInfo; } /* package */ void dispatchActivityCreated(Activity activity, Bundle savedInstanceState) { Object[] callbacks = collectActivityLifecycleCallbacks(); if (callbacks != null) { for (int i=0; i<callbacks.length; i++) { ((ActivityLifecycleCallbacks)callbacks[i]).onActivityCreated(activity, savedInstanceState); } } } /* package */ void dispatchActivityStarted(Activity activity) { Object[] callbacks = collectActivityLifecycleCallbacks(); if (callbacks != null) { for (int i=0; i<callbacks.length; i++) { ((ActivityLifecycleCallbacks)callbacks[i]).onActivityStarted(activity); } } } /* package */ void dispatchActivityResumed(Activity activity) { Object[] callbacks = collectActivityLifecycleCallbacks(); if (callbacks != null) { for (int i=0; i<callbacks.length; i++) { ((ActivityLifecycleCallbacks)callbacks[i]).onActivityResumed(activity); } } } /* package */ void dispatchActivityPaused(Activity activity) { Object[] callbacks = collectActivityLifecycleCallbacks(); if (callbacks != null) { for (int i=0; i<callbacks.length; i++) { ((ActivityLifecycleCallbacks)callbacks[i]).onActivityPaused(activity); } } } /* package */ void dispatchActivityStopped(Activity activity) { Object[] callbacks = collectActivityLifecycleCallbacks(); if (callbacks != null) { for (int i=0; i<callbacks.length; i++) { ((ActivityLifecycleCallbacks)callbacks[i]).onActivityStopped(activity); } } } /* package */ void dispatchActivitySaveInstanceState(Activity activity, Bundle outState) { Object[] callbacks = collectActivityLifecycleCallbacks(); if (callbacks != null) { for (int i=0; i<callbacks.length; i++) { ((ActivityLifecycleCallbacks)callbacks[i]).onActivitySaveInstanceState(activity, outState); } } } /* package */ void dispatchActivityDestroyed(Activity activity) { Object[] callbacks = collectActivityLifecycleCallbacks(); if (callbacks != null) { for (int i=0; i<callbacks.length; i++) { ((ActivityLifecycleCallbacks)callbacks[i]).onActivityDestroyed(activity); } } } private Object[] collectComponentCallbacks() { Object[] callbacks = null; synchronized (mComponentCallbacks) { if (mComponentCallbacks.size() > 0) { callbacks = mComponentCallbacks.toArray(); } } return callbacks; } private Object[] collectActivityLifecycleCallbacks() { Object[] callbacks = null; synchronized (mActivityLifecycleCallbacks) { if (mActivityLifecycleCallbacks.size() > 0) { callbacks = mActivityLifecycleCallbacks.toArray(); } } return callbacks; } }