如何檢查應用程序在前臺的後臺運行在廣播接收器

Question

我想檢查我的應用程序是否在背景或前景，我也希望您在打開的應用程序或不使用廣播接收器

public class CheckRunningApplicationReceiver extends BroadcastReceiver { 
Context mContext; 

public int mId = 1000; 
NotificationManager mNotificationManager; 

@Override 
public void onReceive(Context aContext, Intent anIntent) { 
    mContext = aContext; 
    Boolean isAppOpen = isApplicationSentToBackground(aContext); 
    mNotificationManager = (NotificationManager) mContext.getSystemService(Context.NOTIFICATION_SERVICE); 
    if (isAppOpen) { 
     //openNotification(); 
    } else { 
     //mNotificationManager.cancel(mId); 
    } 

} 

private void openNotification() {// Instantiate notification with icon and 
            // ticker message 
    Notification notification = new Notification(R.drawable.ic_launcher,"Notification message!", System.currentTimeMillis()); 
    PendingIntent i = PendingIntent.getActivity(mContext, 0, new Intent(mContext,MainActivity.class), 0); 
    notification.setLatestEventInfo(mContext, "Notification Created","Click here to see the message", i); 
    notification.flags = Notification.FLAG_ONGOING_EVENT; 
    mNotificationManager.notify(mId, notification); 
} 

public static boolean isApplicationSentToBackground(final Context context) { 
    ActivityManager am = (ActivityManager) context.getSystemService(Context.ACTIVITY_SERVICE); 
    List<RunningTaskInfo> tasks = am.getRunningTasks(1); 
    if (!tasks.isEmpty()) { 
     ComponentName topActivity = tasks.get(0).topActivity; 
     if (!topActivity.getPackageName().equals(context.getPackageName())) { 
      return true; 
     } 
    } 

    return false; 
} 

}

是否有任何解決方案，幫助我， 謝謝。

Answer 1

即使應用程序處於後臺，由於接收器拾取的事件全局發送，並且每個應用程序都已註冊以偵聽這些應用程序，無論應用程序是否在運行，BroadcastReceiver都能正常工作。

爲了解決這個問題，在您的BroadcastReceiver的onReceive代碼中，檢查您的應用程序是否在前臺。

我知道有一個 - 也是唯一一個 - 始終如一的有效方法來做到這一點。您需要跟蹤您的應用程序的暫停/恢復操作。確保您在每項活動中都檢查了這一點。

這個answer中有一些示例代碼。在你的情況下，你需要先檢查MyApplication.isActivityVisible（）== true作爲驗證，然後再從你的BroadcastReceiver中做任何事情。

Answer 2

在您的活動註冊廣播接收器檢查活動在前景或背景。

StackAnswer.java 
public class StackAnswer extends Activity { 
    public static final int IS_ALIVE = Activity.RESULT_FIRST_USER; 
    public static final String CHECK_ALIVE_ACTION = "CHECK_ALIVE_ACTION"; 
    private BroadcastReceiver mRefreshReceiver; 


    @Override 
    protected void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 
     setContentView(R.layout.activity_main); 
     mRefreshReceiver = new BroadcastReceiver() { 
      @Override 
      public void onReceive(Context context, Intent intent) { 

       Log.i("onReceive","BroadcastIntent received in MainActivity"); 

       // TODO:     
       // Check to make sure this is an ordered broadcast 
       // Let sender know that the Intent was received 
       // by setting result code to MainActivity.IS_ALIVE 
       setResultCode(MainActivity.IS_ALIVE); 
      } 
     }; 
    } 



    // Register the BroadcastReceiver 
    @Override 
    protected void onResume() { 
     super.onResume(); 

     // TODO: 
     // Register the BroadcastReceiver to receive a 
     // DATA_REFRESHED_ACTION broadcast 
     IntentFilter filter = new IntentFilter(); 
     filter.addAction(CHECK_ALIVE_ACTION);   
     registerReceiver(mRefreshReceiver, filter);  

    } 

    @Override 
    protected void onPause() { 

     // TODO: 
     // Unregister the BroadcastReceiver if it has been registered 
     // Note: To work around a Robotium issue - check that the BroadcastReceiver 
     // is not null before you try to unregister it 
     if(mRefreshReceiver!=null){ 
      unregisterReceiver(mRefreshReceiver); 
     } 
     super.onPause(); 
    } 


} 

發送從後臺播放檢查天氣活動是活着還是不

BackgroundTask.java 
    public class BackgroundTask { 

    private void checkIfForeground (Context mApplicationContext){ 
     mApplicationContext.sendOrderedBroadcast(new Intent(
       StackAnswer.CHECK_ALIVE_ACTION), null, 
       new BroadcastReceiver() { 
      @Override 
      public void onReceive(Context context, Intent intent) { 
       // TODO: Check whether the result code is not MainActivity.IS_ALIVE 
       if (getResultCode() != StackAnswer.IS_ALIVE) { 
        //Background 
       }else{ 
        //Foreground 
       } 
      } 
     }, null, 0, null, null); 
    } 
}