Question

我遇到以下代码的问题，无法获取媒体按钮的操作。

Class MediaButtonIntentReceiver：

import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.util.Log;
import android.view.KeyEvent;

public class MediaButtonIntentReceiver extends BroadcastReceiver {

public MediaButtonIntentReceiver() {
    super();
}

@Override
public void onReceive(Context context, Intent intent) {
    String intentAction = intent.getAction();
    if (Intent.ACTION_MEDIA_BUTTON.equals(intentAction)) {
        KeyEvent event = (KeyEvent) intent
                .getParcelableExtra(Intent.EXTRA_KEY_EVENT);
        int action = event.getAction();
        if (action == KeyEvent.ACTION_DOWN) {
            Log.i("ok", "media button pressed");
        }

    }

    if (isOrderedBroadcast()) {
        abortBroadcast();
    }
}
}

在我的主要内容中我有这个：

MediaButtonIntentReceiver mMediaButtonReceiver = new MediaButtonIntentReceiver();
IntentFilter mediaFilter = new IntentFilter(Intent.ACTION_MEDIA_BUTTON);
mediaFilter.setPriority(IntentFilter.SYSTEM_HIGH_PRIORITY);
registerReceiver(mMediaButtonReceiver, mediaFilter);

这是我清单上的接收器

<receiver android:name="ch.bono88.Ederly.MediaButtonIntentReceiver">
     <intent-filter>
          <action android:name="android.intent.action.MEDIA_BUTTON"/>
     </intent-filter>
</receiver>

所以当我尝试执行我的应用程序时，我得到了这个异常

java.lang.RuntimeException: Unable to start receiver ch.bono88.Ederly.MediaButtonIntentReceiver: java.lang.NullPointerException
Caused by: java.lang.NullPointerException
at ch.bono88.Ederly.MediaButtonIntentReceiver.onReceive(MediaButtonIntentReceiver.java:26)

Answer 1

您需要检查MediaButtonIntentReceiver源中的确切第26行。我可以间接地断定你需要为事件检查null，因为它可以为null。

媒体按钮接收器android

1 个答案: