Android 按键 按键盘的音量+/-，静音键后屏幕音量条没有出来

frameworks/base/services/core/java/com/android/server/policy/PhoneWindowManager.java

public int interceptKeyBeforeQueueing(KeyEvent event, int policyFlags) {
      case KeyEvent.KEYCODE_VOLUME_DOWN:
            case KeyEvent.KEYCODE_VOLUME_UP:
            case KeyEvent.KEYCODE_VOLUME_MUTE: {
                //result &= ~ACTION_PASS_TO_USER;     △如果加了这一句，其他按键就无法正常工作
                isWakeKey = true;

            case KeyEvent.KEYCODE_MEDIA_PAUSE:
            case KeyEvent.KEYCODE_MEDIA_PLAY_PAUSE:
            case KeyEvent.KEYCODE_HEADSETHOOK:
            case KeyEvent.KEYCODE_MUTE:
            case KeyEvent.KEYCODE_MEDIA_NEXT:
            case KeyEvent.KEYCODE_MEDIA_PREVIOUS:
            case KeyEvent.KEYCODE_MEDIA_REWIND:
            case KeyEvent.KEYCODE_MEDIA_RECORD:
            case KeyEvent.KEYCODE_MEDIA_FAST_FORWARD:
            case KeyEvent.KEYCODE_MEDIA_AUDIO_TRACK: {
               // result &= ~ACTION_PASS_TO_USER;         同理
                isWakeKey = true;