ANDROID 完美退出APP的实例代码

public class AgentApplication extends Application { 

    private List<Activity> activities = new ArrayList<Activity>(); 

        public void addActivity(Activity activity) { 
            activities.add(activity); 
        } 

        @Override 
        public void onTerminate() { 
            super.onTerminate(); 

            for (Activity activity : activities) { 
                activity.finish(); 
            } 

            onDestroy(); 

            System.exit(0); 
        } 
    }