Question

我的应用程序中有一个服务在后端运行，当我按下按钮音量时服务可以启动，当我按下按钮音量时停止服务。

public class SettingsContentObserver extends ContentObserver {


int previousVolume;
Context context;

public SettingsContentObserver(Context c, Handler handler) {
    super(handler);
    context=c;

    AudioManager audio = (AudioManager)        context.getSystemService(Context.AUDIO_SERVICE);
    previousVolume = audio.getStreamVolume(AudioManager.STREAM_RING);

}



@Override
public boolean deliverSelfNotifications() {
    return super.deliverSelfNotifications();
}

@Override
public void onChange(boolean selfChange) {
    super.onChange(selfChange);

    AudioManager audio = (AudioManager) context.getSystemService(Context.AUDIO_SERVICE);
    int currentVolume = audio.getStreamVolume(AudioManager.STREAM_RING);

    int delta=previousVolume-currentVolume;



        if(delta > 0)
        {
            System.out.println("Decreased") ;
            Intent intent = new Intent(context, MyAlarmService.class);
            context.stopService(intent);
            previousVolume=currentVolume;
        }
        else if(delta < 0)
        {
              System.out.println("Increased");
              Intent intent = new Intent(context, MyAlarmService.class);
              context.startService(intent);
              previousVolume=currentVolume;
        }


}
}

当我的手机被锁定时（屏幕关闭时）我想做同样的事情，当我在网上搜索时，我发现我必须使用BroadcastReceivre，我测试它但它不起作用。

public class YourBoardcastReceiver extends BroadcastReceiver {
    @Override
public void onReceive(Context context, Intent intent) {


    Log.e("get something", "i dont know what!!");

    String intentAction = intent.getAction();
    KeyEvent event = null;
    if (Intent.ACTION_MEDIA_BUTTON.equals(intentAction)) {
        event = (KeyEvent) intent
            .getParcelableExtra(Intent.EXTRA_KEY_EVENT);
    }

    if (event == null) {
        return;
    }

    int keycode = event.getKeyCode();
    int action = event.getAction();
    long eventtime = event.getEventTime();

    if (keycode == KeyEvent.KEYCODE_MEDIA_PLAY_PAUSE
        || keycode == KeyEvent.KEYCODE_HEADSETHOOK) {
    if (action == KeyEvent.ACTION_DOWN) {

            Intent intent1 = new Intent(context, MyAlarmService.class);
            context.stopService(intent1);

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

        else if (action == KeyEvent.ACTION_UP) {

              Intent intent11 = new Intent(context, MyAlarmService.class);
              context.startService(intent11);

        }

            if (isOrderedBroadcast()) {
                abortBroadcast();


    }
}
}
}


}

在android清单中我添加：

<receiver android:name="YourBoardcastReceiver">
            <intent-filter>
                    <action android:name="android.intent.action.SCREEN_ON" />
            </intent-filter>
    </receiver>

在关于方法oncrete的mainActivity中我添加：

AudioManager mAudioManager = (AudioManager) getSystemService(Context.AUDIO_SERVICE);
ComponentName mRemoteControlResponder = new ComponentName(getPackageName(),
YourBoardcastReceiver.class.getName());

请求我可以给我一些帮助，认为

Answer 1

当手机处于锁定/睡眠模式时我们无法听到按钮的变化，但是我们可以做一些黑客来听音量按钮。

Github：https://github.com/praslnx8/volume_Screen_Lock

这些应用程序正在播放背景为0卷的媒体，然后通过MediaButtonIntent

将始终使用Reciever收听密钥

Answer 2

尝试注册BroadCast Receiver for Intent.ACTION_SCREEN_OFF和Intent.ACTION_SCREEN_ON

当手机被锁定时，听音量按钮

2 个答案: