为什么ACTION_MEDIA_BUTTON无法处理事件?

时间:2013-02-24 22:14:24

标签: android broadcastreceiver android-audiomanager

在关于如何use hardware playback control keys to control audio playback的培训部分之后,我创建了一个监听器类:

public class RemoteControlReceiver extends BroadcastReceiver {
    @Override
    public void onReceive(Context arg0, Intent intent) {
        if (Intent.ACTION_MEDIA_BUTTON.equals(intent.getAction())) {
            KeyEvent event = (KeyEvent)intent.getParcelableExtra(Intent.EXTRA_KEY_EVENT);
            Log.e(TAG, "ACTION_MEDIA_BUTTON"); 

            int keycode = event.getKeyCode();
            switch (keycode)
            {
                case KeyEvent.KEYCODE_MEDIA_NEXT:
                    Log.e(TAG, "KEYCODE_MEDIA_NEXT"); 
                    break;
                case KeyEvent.KEYCODE_MEDIA_PLAY_PAUSE:
                    Log.e(TAG, "KEYCODE_MEDIA_PLAY_PAUSE"); 
                    break;
                case KeyEvent.KEYCODE_MEDIA_PREVIOUS:
                    Log.e(TAG, "KEYCODE_MEDIA_PREVIOUS"); 
                    break;
                default:
            }

            if (/*KeyEvent.KEYCODE_MEDIA_PLAY*/ 126 == event.getKeyCode()) { // KEYCODE_MEDIA_PLAY undefined for API < 11
                Log.e(TAG, "KEYCODE_MEDIA_PLAY"); 
            }           
        }
    }
}

在活动的onCreate()中注册:

private AudioManager mAudioManager;
private ComponentName mRemoteControlReceiver;
...
...
mAudioManager = (AudioManager)getSystemService(Context.AUDIO_SERVICE);
mRemoteControlReceiver = new ComponentName(this, RemoteControlReceiver.class);
mAudioManager.registerMediaButtonEventReceiver(mRemoteControlReceiver);

并将其注册在清单中:

<receiver android:name=".RemoteControlReceiver">
    <intent-filter>
        <action android:name="android.intent.action.MEDIA_BUTTON" />
    </intent-filter>
</receiver>

但是当按下任何这些按钮时,不会导致LogCat上出现任何日志消息! (无论是否在播放媒体时被按下)

我的代码似乎拦截了其他媒体播放器的这些事件,但为什么我看不到任何Log.e()消息?我错过了什么?

顺便说一句,当我按下任何一个按钮时,会出现以下消息:

W/KeyCharacterMap(19801): Can't open keycharmap file
W/KeyCharacterMap(19801): Error loading keycharmap file '/system/usr/keychars/h2w_headset.kcm.bin'. hw.keyboards.131075.devname='h2w headset'
W/KeyCharacterMap(19801): Using default keymap: /system/usr/keychars/qwerty.kcm.bin

1 个答案:

答案 0 :(得分:3)

您是否碰巧使用Library Project来实现此目的?

如果是这样,哪个清单你把<receiver>放进去了?图书馆或应用程序的?

如果您放入图书馆,它将无法使用。您必须将其放在应用程序的清单中:

<receiver android:name=".RemoteControlReceiver">
    <intent-filter>
        <action android:name="android.intent.action.MEDIA_BUTTON" />
    </intent-filter>
</receiver>