Android seekbar（自定义）控制音量同步更新

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" 
  android:id="@+id/ringtone_seekbar_parent" 
  android:layout_width="match_parent" 
  android:layout_height="160px" 
  android:layout_marginTop="0dip" 
  android:layout_weight="1" 
  android:gravity="center_vertical" 
  android:orientation="horizontal" > 
 
  <ImageView 
    android:layout_width="wrap_content" 
    android:layout_height="wrap_content" 
    android:layout_marginLeft="25dip" 
    android:background="@drawable/zf_notify_quicksetting_ringtone" /> 
 
  <SeekBar 
    android:id="@+id/ringtone_seekbar" 
    android:layout_width="fill_parent" 
    android:layout_height="wrap_content" 
    android:layout_marginRight="10dp" 
    android:maxHeight="49px" 
    android:minHeight="49px" 
    android:paddingEnd="40dp" 
    android:paddingStart="25dp" 
    android:progress="60" 
    android:progressDrawable="@drawable/zf_progress_horizontal" 
    android:splitTrack="false" 
    android:thumb="@drawable/zf_noti_scrubber_control_normal" 
    android:thumbOffset="0px" /> 
 
</LinearLayout> 

<?xml version="1.0" encoding="utf-8"?> 
 
<layer-list xmlns:android="http://schemas.android.com/apk/res/android"> 
   
  <item android:id="@android:id/background" android:drawable="@drawable/progress_gray"/> 
   
  <item android:id="@android:id/progress" android:drawable="@drawable/progress_blue"/> 
   
</layer-list> 

AudioManager audioManager = (AudioManager) context.getSystemService(Context.AUDIO_SERVICE);//获取媒体系统服务 
mVoiceSeekBar= (SeekBar) mStatusBarWindow.findViewById(R.id.ringtone_seekbar);//注册ID 
mVoiceSeekBar.setMax(15);//设置最大音量 
mVoiceSeekBar.setProgress(audioManager.getStreamVolume(AudioManager.STREAM_MUSIC));// 当前的媒体音量 
myRegisterReceiver();//注册同步更新的广播 
Log.i("lyj_ring", "mVoiceSeekBar max voluem = "+audioManager.getStreamMaxVolume(AudioManager.STREAM_SYSTEM)); 
mVoiceSeekBar.setOnSeekBarChangeListener(new OnSeekBarChangeListener() { 
       
  public void onStopTrackingTouch(SeekBar arg0) { 
    // TODO Auto-generated method stub 
        
  } 
       
  public void onStartTrackingTouch(SeekBar arg0) { 
    // TODO Auto-generated method stub 
         
  } 
public void onProgressChanged(SeekBar arg0, int arg1, boolean arg2) { 
      AudioManager audioManager = (AudioManager) context.getSystemService(Context.AUDIO_SERVICE); 
      Log.v("lyj_ring", "mVoiceSeekBar max progress = "+arg1); 
      //系统音量和媒体音量同时更新 
      audioManager.setStreamVolume(AudioManager.STREAM_SYSTEM, arg1, 0); 
      audioManager.setStreamVolume(3, arg1, 0);// 3 代表 AudioManager.STREAM_MUSIC 
     } 
    }); 
mVoiceObserver = new ContentObserver(new Handler()) { 
     @Override 
     public void onChange(boolean selfChange) { 
       // TODO Auto-generated method stub 
       super.onChange(selfChange); 
       AudioManager audioManager = (AudioManager) context.getSystemService(Context.AUDIO_SERVICE); 
       mVoiceSeekBar.setProgress(audioManager.getStreamVolume(AudioManager.STREAM_SYSTEM)); 
       //或者你也可以用媒体音量来监听改变，效果都是一样的。 
       //mVoiceSeekBar.setProgress(audioManager.getStreamVolume(AudioManager.STREAM_MUSIC)); 
      } 
    }; 

 /** 
  * 注册当音量发生变化时接收的广播 
  */ 
  private void myRegisterReceiver(){ 
  MyVolumeReceiver mVolumeReceiver = new MyVolumeReceiver() ; 
    IntentFilter filter = new IntentFilter() ; 
    filter.addAction("android.media.VOLUME_CHANGED_ACTION") ; 
    mContext.registerReceiver(mVolumeReceiver, filter) ; 
  } 
   
  /** 
  * 处理音量变化时的界面显示 
  * @author long 
  */ 
  private class MyVolumeReceiver extends BroadcastReceiver{ 
    @Override 
    public void onReceive(Context context, Intent intent) { 
      //如果音量发生变化则更改seekbar的位置 
      if(intent.getAction().equals("android.media.VOLUME_CHANGED_ACTION")){ 
      AudioManager mAudioManager = (AudioManager) context.getSystemService(Context.AUDIO_SERVICE); 
        int currVolume = mAudioManager.getStreamVolume(AudioManager.STREAM_MUSIC) ;// 当前的媒体音量 
        mVoiceSeekBar.setProgress(currVolume) ; 
      } 
    } 
  }