IntentService响应死亡ResultReceiver

Question

活动实例化ResultReceiver并重写onReceiveResult。然后，该活动向IntentService发送一个Intent，并将ResultReceiver作为一个额外的参数。 IntentService完成处理后，它会将消息发送回ResultReceiver并在onReceiveResult中进行处理。

问题是，如果用户导航离开Activity然后结果仍然发回到导致所有类型的问题的ResultReceiver。有没有办法阻止这种行为？我试着停止活动的onDestroy（）中的IntentService，但结果仍然返回。

下面是一个简单的活动

public class Foo extends Activity { 
    @Override 
    public void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 

     Intent i = new Intent(this, SampleIntentService.class); 
     i.putExtra("receiver", mReceiver); 
     startService(i); 
    } 

    @Override 
    public void onDestroy() { 
     stopService(new Intent(this, SampleIntentService.class)); 
     mReceiver = null; 
     super.onDestroy(); 
    } 

    ResultReceiver mReceiver = new ResultReceiver(new Handler()) { 
     @Override 
     protected void onReceiveResult(int resultCode, Bundle resultData) { 
      // Handle response from IntentService here 
     } 
    }; 
} 

下面是一个简单IntentService

public class SampleIntentService extends IntentService { 
    public SampleIntentService() { 
     super(SampleIntentService.class.getName()); 
    } 

    @Override 
    protected void onHandleIntent(Intent intent) { 
    ResultReceiver rec = intent.getParcelableExtra("receiver"); 
     if (rec != null) { 
      rec.send(200, null); 
     } 
    } 
} 

Answer 1

我通过创建自定义ResultReceiver如下解决了这个问题。

public class SampleResultReceiver extends ResultReceiver { 
    private Receiver mReceiver; 

    public SampleResultReceiver(Handler handler) { 
     super(handler); 
    } 

    public void setReceiver(Receiver receiver) { 
     mReceiver = receiver; 
    } 

    public interface Receiver { 
     void onReceiveResult(int resultCode, Bundle resultData); 
    } 

    @Override 
    protected void onReceiveResult(int resultCode, Bundle resultData) { 
     if (mReceiver != null) { 
      mReceiver.onReceiveResult(resultCode, resultData); 
     } 
    } 
} 

然后在我的活动我做到以下几点：

public class Foo extends Activity implements Receiver { 
    private SampleResultReceiver mReceiver; 

    @Override 
    public void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 

     mReceiver = new SampleResultReceiver(new Handler()); 
     mReceiver.setReceiver(this); 

     Intent i = new Intent(this, SampleIntentService.class); 
     i.putExtra("receiver", mReceiver); 
     startService(i); 
    } 

    @Override 
    public void onDestroy() { 
     if (mReceiver != null) { 
      mReceiver.setReceiver(null); 
     } 
     super.onDestroy(); 
    } 

    @Override 
    protected void onReceiveResult(int resultCode, Bundle resultData) { 
     // Handle response from IntentService here 
    } 
} 

这将导致发送到您的自定义ResultReceiver无处结束了任何消息的活动已被破坏后:)