搜索栏因为单击设备按钮后音量不变答案

【问题标题】：Seek Bar As volume not changing upon clicking on Device buttons搜索栏因为单击设备按钮后音量不变
【发布时间】：2014-01-05 12:22:22
【问题描述】：

好的，所以我让我的搜索栏来更改音量，这部分正在工作。但是当我改变手机按钮的音量时，屏幕上的搜索栏保持不变。问题：当我增加/减少电话按钮的音量时，SeekBar 没有移动增加减少。如何设置？

import android.widget.SeekBar;
import android.widget.SeekBar.OnSeekBarChangeListener;
 private SeekBar volumeSeekbar = null;
private AudioManager audioManager = null; 

     private void initControls()
    {
        try
        {
            volumeSeekbar = (SeekBar)findViewById(R.id.seekBar1);
            audioManager = (AudioManager) getSystemService(Context.AUDIO_SERVICE);
            volumeSeekbar.setMax(audioManager
                    .getStreamMaxVolume(AudioManager.STREAM_MUSIC));
            volumeSeekbar.setProgress(audioManager
                    .getStreamVolume(AudioManager.STREAM_MUSIC));   


            volumeSeekbar.setOnSeekBarChangeListener(new 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();
        }
    }

【问题讨论】：

stackoverflow.com/questions/10134338/…
和我的代码一样，点击硬件按钮不会改变

标签： android button device volume seekbar

【解决方案1】：

这很正常，因为您需要在使用硬件音量按钮时要求得到通知。

我看到该类型问题的多个答案，似乎这个答案是一个普遍的答案：

Is there a broadcast action for volume changes?

【讨论】：

【解决方案2】：

private void initControls() {
    // Return the handle to a system-level service - 'AUDIO'.
    audioManager = (AudioManager) getSystemService(Context.AUDIO_SERVICE);

    // Find the seekbar 1
    mediaVlmSeekBar = (SeekBar) findViewById(R.id.seekBar1);
    // Set the max range(Volume in this case) of seekbar
    // for Media player volume
    mediaVlmSeekBar.setMax(audioManager
            .getStreamMaxVolume(AudioManager.STREAM_MUSIC));
    // Set the progress with current Media Volume
    mediaVlmSeekBar.setProgress(audioManager
            .getStreamVolume(AudioManager.STREAM_MUSIC));

    try {
        // Listener to receive changes to the SeekBar1's progress level
        mediaVlmSeekBar
                .setOnSeekBarChangeListener(new OnSeekBarChangeListener() {
                    public void onStopTrackingTouch(SeekBar arg0) {
                    }

                    public void onStartTrackingTouch(SeekBar arg0) {
                    }

                    // When progress level of seekbar1 is changed
                    public void onProgressChanged(SeekBar arg0,
                            int progress, boolean arg2) {
                        audioManager.setStreamVolume(
                                AudioManager.STREAM_MUSIC, progress, 0);
                    }
                });
    } catch (Exception e) {
        e.printStackTrace();
    }
}

public boolean onKeyDown(int keyCode, KeyEvent event) {
      if (keyCode == KeyEvent.KEYCODE_VOLUME_UP) 
     { 
          mediaVlmSeekBar = (SeekBar) findViewById(R.id.seekBar1);
            int index = mediaVlmSeekBar.getProgress(); 
            mediaVlmSeekBar.setProgress(index + 1); 
            return true; 
     } else if (keyCode == KeyEvent.KEYCODE_VOLUME_DOWN)
      {
            int index = mediaVlmSeekBar.getProgress(); 
            mediaVlmSeekBar.setProgress(index - 1); 
            return true; 
     }
      return super.onKeyDown(keyCode, event); 
     }

【讨论】：