如何在自定義TextView中註冊broadcastreceiver

Question

我想獲得在自定義textview中工作的BroadcastReceiver。我用這個代碼，但沒有收到任何東西。然而，setText（「準備好接收」）工作正常。

public class ArefinBatteryTextView extends TextView { 
    private BroadcastReceiver receiver = new BroadcastReceiver() { 
     @Override 
     public void onReceive(Context context, Intent intent) { 
      setText("received"); 
     } 
    }; 

    public ArefinBatteryTextView(Context context) { 
     super(context); 

    } 

public ArefinBatteryTextView(Context context, AttributeSet attrs) { 
    super(context, attrs); 
    setTextColor(Color.GREEN); 
    setTextSize(75); 
    setText("Ready for receiving"); 

    LocalBroadcastManager lbm =  LocalBroadcastManager.getInstance(context); 
    lbm.registerReceiver(receiver, new IntentFilter(Intent.ACTION_BATTERY_CHANGED)); 

} 

public ArefinBatteryTextView(Context context, AttributeSet attrs, int defStyle) { 
    super(context, attrs, defStyle); 


} 

protected void onDraw (Canvas canvas) { 
    super.onDraw(canvas); 


} 


} 

如何正確註冊接收器以使其正常工作？

Answer 1

你寫的IMO代碼有點奇怪。視圖不應該在MVC體系結構中保存邏輯..視圖僅用於查看目的。視圖控制器可以更改視圖的值。所以請好好使用TextView，並在Activity（Controller）中定義您的廣播接收器並設置值。 我相信我不會讓你感到困惑 http://developer.android.com/training/monitoring-device-state/battery-monitoring.html

Answer 2

不知道爲什麼你們認爲這是不可能的，但我已經做到了。這是這樣做的。

public ArefinBatteryTextView(Context context, AttributeSet attrs) { 
    super(context, attrs); 
    setTextColor(Color.GREEN); 
    setTextSize(75); 
    setText("Ready for receiving"); 

    context.registerReceiver(new BroadcastReceiver() { 
     @Override 
     public void onReceive(Context context, Intent intent) { 
      int a = intent.getIntExtra(BatteryManager.EXTRA_LEVEL,0); 
      setText(""+a); 
     } 
    }, new IntentFilter(Intent.ACTION_BATTERY_CHANGED)); 

}