java - Android SeekBar 更新音量按钮点击

Question

我正在尝试将 Seekbar 与设备的音量同步，并在用户使用按钮设置音量时更新它。但似乎并没有保持同步。有时只更新一次就停止。

try
    {
        final AudioManager audioManager = (AudioManager) getSystemService(Context.AUDIO_SERVICE);
        mVolume.setMax(audioManager
                .getStreamMaxVolume(AudioManager.STREAM_MUSIC));
        mVolume.setProgress(audioManager
                .getStreamVolume(AudioManager.STREAM_MUSIC));


        mVolume.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener()
        {
            @Override
            public void onStopTrackingTouch(SeekBar arg0)
            {
            }

            @Override
            public void onStartTrackingTouch(SeekBar arg0)
            {
            }

            @Override
            public void onProgressChanged(SeekBar arg0, int progress, boolean arg2)
            {
                audioManager.setStreamVolume(AudioManager.STREAM_MUSIC,
                        progress, 0);
            }
        });
    }
    catch (Exception e)
    {
        e.printStackTrace();
    }

点击音量按钮:

    @Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
    final AudioManager audioManager = (AudioManager) getSystemService(Context.AUDIO_SERVICE);
    if (keyCode == KeyEvent.KEYCODE_VOLUME_DOWN) {
        try{
            mVolume.setProgress(audioManager
                    .getStreamVolume(AudioManager.STREAM_MUSIC) - 1);
        } catch (Error e) {
            // min value
        }
    } else if (keyCode == KeyEvent.KEYCODE_VOLUME_UP) {
        try{
            mVolume.setProgress(audioManager
                    .getStreamVolume(AudioManager.STREAM_MUSIC) + 1);
        } catch (Error e) {
            // max value
        }
    }
    return super.onKeyDown(keyCode, event);
}

Answer 1

我在我的seekBar中使用这个方法

    private boolean setVolumeMultimedia(int volume) {
    AudioManager audioManager = (AudioManager) mActivity.getSystemService(Context.AUDIO_SERVICE);
    if (audioManager == null) {
        NMPLog.e(TAG, "Unexpected null AudioManager. Unable to get/set the volume/mute.");
        return false;
    }
    audioManager.setStreamVolume(AudioManager.STREAM_MUSIC, volume, AudioManager.FLAG_PLAY_SOUND);
    NMPLog.i(TAG, "Volume of session: " + audioManager.getStreamVolume(AudioManager.STREAM_MUSIC));
    return true;
}

我通过audioManager.setStreamVolume(AudioManager.STREAM_MUSIC,volume,AudioManager.FLAG_PLAY_SOUND);而不是 0。AudioManager.FLAG_PLAY_SOUND 是整数 4。

您可以设置此标志。

public static final int FLAG_ALLOW_RINGER_MODES = 2;
public static final int FLAG_PLAY_SOUND = 4;
public static final int FLAG_REMOVE_SOUND_AND_VIBRATE = 8;
public static final int FLAG_SHOW_UI = 1;
public static final int FLAG_VIBRATE = 16;