以下是一个使用SeekBar来调节系统音量的实例：
1、XML：
<SeekBar
android: /> //滑块样式
2、seekbar_style.xml:
<?xml version="1.0" encoding="UTF-8"?>
<layer-list xmlns:andro />
</shape>
</clip>
</item>
</layer-list>
3、thumb.xml:
<?xml version="1.0" encoding="UTF-8"?>
<selector xmlns:andro
/>
</selector>
4、bacon_seekbar.xml:
<layer-list
xmlns:andro />
</layer-list>
5、JAVA代码：
public class PianoActivity extends Activity {
/** Called when the activity is first created. */
private ImageButton imageButton_white1;
private MediaPlayer mediaPlayer01;
public AudioManager audiomanage;
private TextView mVolume ; //显示当前音量
public SeekBar soundBar;
private int maxVolume, currentVolume;
private int volume=0; //初始化声音
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
mediaPlayer01 = new MediaPlayer();
imageButton_white1=(ImageButton)findViewById(R.id.white1);
final SeekBar soundBar=(SeekBar)findViewById(R.id.sound); //音量设置
mVolume = (TextView)findViewById(R.id.mVolume);
audiomanage = (AudioManager)getSystemService(Context.AUDIO_SERVICE);
maxVolume = audiomanage.getStreamMaxVolume(AudioManager.STREAM_MUSIC); //获取系统最大音量
soundBar.setMax(maxVolume); //拖动条最高值与系统最大声匹配
currentVolume = audiomanage.getStreamVolume(AudioManager.STREAM_MUSIC); //获取当前值
soundBar.setProgress(currentVolume);
mVolume.setText(currentVolume*100/maxVolume + " %");
soundBar.setOnSeekBarChangeListener(new OnSeekBarChangeListener(){////调音监听器
public void onProgressChanged(SeekBar arg0,int progress,boolean fromUser){
audiomanage.setStreamVolume(AudioManager.STREAM_MUSIC, progress, 0);
currentVolume = audiomanage.getStreamVolume(AudioManager.STREAM_MUSIC); //获取当前值
soundBar.setProgress(currentVolume);
mVolume.setText(currentVolume*100/maxVolume + " %");
}
@Override
public void onStartTrackingTouch(SeekBar seekBar) {
// TODO Auto-generated method stub
}
@Override
public void onStopTrackingTouch(SeekBar seekBar) {
// TODO Auto-generated method stub
}
});