Android activitylifecyclecallbacks

Android activitylifecyclecallbacks

package com.cc;import java.util.LinkedList;import android.app.Activity;import android.app.Application;import android.os.Bundle;/** * Demo示例: * ActivityLifecycleCallbacks使用示例 *  * ActivityLifecycleCallbacks用于对应用中Activity的生命周期的追踪和回调 *  * 使用ActivityLifecycleCallbacks可实现: * 1 判断App是否在后台运行 * 2 关闭该应用所有Activity *  *  * (1)判断App是否在后台运行 * 在该实现中采用activityCounter记录Activity的个数. * 通过对于activityCounter是否为0判断当前APP是否在前台运行. *  * 从ActivityLifecycleCallbacks的实现方法中我们的惯性思维是: * 在ActivityLifecycleCallbacks的onActivityResumed()中activityCounter+1. * 在onActivityPaused()中activityCounter-1, * 但是这么对么？ *  * 先看一下界面跳转时两个Activity的生命周期 * 当从Activity A跳转到Activity B时,两个Activity的生命周期如下: * A.onPause()->B.onCreate()->B.onStart()-> B.onResume()-> A.onStop() *  * 假若按照上述方式那么: * 在A启动后activityCounter=1; * 当从A跳转到B时在调用A.onPause()时执行:activityCounter-1=0; * 即该APP运行在后台. * 这当然是错的,两个界面切换的过程中APP当然是运行在前台的。 *  * 如下修改: * 在onActivityStarted()中对于activityCounter+1 * 在onActivityStopped()中对于activityCounter-1 * 小结:注意Activity跳转时的生命周期 *  * (2)关闭该应用所有Activity *    2.1 利用LinkedList<Activity>管理应用中的界面 *    2.2 在ActivityLifecycleCallbacks的onActivityCreated() *        将Activity添加到LinkedList中 *        在ActivityLifecycleCallbacks的onActivityDestroyed() *        将Activity从LinkedList中移除 *    2.3 关闭应用时销毁LinkedList中所有Activity *  * 备注说明: * 1 ActivityLifecycleCallbacks是在API 14及其以上才有的 * 2 在Android4.0以下可以在BaseActivity中按照该思路实现 * */public class MyApplication extends Application {private static int activityCounter=0;private static MyApplication mApplicationInstance;private static LinkedList<Activity> mActivityLinkedList;private ActivityLifecycleCallbacksImpl mActivityLifecycleCallbacksImpl;@Overridepublic void onCreate() {    super.onCreate();    mApplicationInstance=new MyApplication();    mActivityLinkedList=new LinkedList<Activity>();    mActivityLifecycleCallbacksImpl=new ActivityLifecycleCallbacksImpl();    this.registerActivityLifecycleCallbacks(mActivityLifecycleCallbacksImpl);}public static MyApplication getInstance() {    if (null==mApplicationInstance) {        mApplicationInstance=new MyApplication();    }    return mApplicationInstance;}//判断App是否在后台运行public boolean isAppRunningBackground(){    boolean flag=false;    if(activityCounter==0){        flag=true;    }    return flag;}//退出应用public void finishAllActivity(){    //unregisterActivityLifecycleCallbacks(mActivityLifecycleCallbacksImpl);    System.out.println("--> mActivityLinkedList.size()="+mActivityLinkedList.size());    if(null!=mActivityLinkedList){        for(Activity activity:mActivityLinkedList){            if(null!=activity){                activity.finish();            }        }    }}private class ActivityLifecycleCallbacksImpl implements ActivityLifecycleCallbacks{    @Override    public void onActivityCreated(Activity activity, Bundle savedInstanceState) {        System.out.println("onActivityCreated --> "+activity.getClass().getName());        if (null!=mActivityLinkedList&&null!=activity) {            mActivityLinkedList.addFirst(activity);        }    }    @Override    public void onActivityStarted(Activity activity) {        activityCounter++;        System.out.println("onActivityStarted --> "+activity.getClass().getName()+",activityCounter="+activityCounter);    }    @Override    public void onActivityResumed(Activity activity) {        System.out.println("onActivityResumed --> "+activity.getClass().getName());    }    @Override    public void onActivityPaused(Activity activity) {        System.out.println("onActivityPaused --> "+activity.getClass().getName());    }    @Override    public void onActivityStopped(Activity activity) {        activityCounter--;        System.out.println("onActivityStopped --> "+activity.getClass().getName()+",activityCounter="+activityCounter);    }    @Override    public void onActivitySaveInstanceState(Activity activity, Bundle outState) {        System.out.println("onActivitySaveInstanceState --> "+activity.getClass().getName());    }    @Override    public void onActivityDestroyed(Activity activity) {        System.out.println("onActivityDestroyed --> "+activity.getClass().getName());        if (null!=mActivityLinkedList&&null!=activity) {            if (mActivityLinkedList.contains(activity)) {                mActivityLinkedList.remove(activity);            }        }    }}

}