MediaPlayer 播放声音大小设置
1、 private MediaPlayer mp;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mp = MediaPlayer.create(this, R.raw.xjwq);
mp.start();
mp.setLooping(true);
}

2、这样是能够正常播放的然后我就想做一个按钮来切换这个播放的声音。我这么做了,
Java code
private MediaPlayer mp1;
private MediaPlayer mp2;
private MediaPlayer mp3;

3、@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mp1 = MediaPlayer.create(this, R.raw.xjwq);
mp2 = MediaPlayer.create(this, R.raw.bg);
mp3 = MediaPlayer.create(this, R.raw.xghzj);
mp1.start();
mp1.setLooping(true);
}

4、然后在按钮内执行
C/C++ code
?
switch(mpIndex)
{
case 0:
mp1.stop();
break;
case 1:
mp2.stop();
break;
case 2:
mp3.stop();
break;
}

5、 mpIndex ++;
if(mpIndex == 3) mpIndex = 0;
if(mpIndex == 0)
{ mp1.start();
mp1.setLooping(true);else if(mpIndex == 1)
{ mp2.start();
mp2.setLooping(true) else
{
mp3.start();
mp3.setLooping(true);
}

6、我就想循环的播放资源文件里面的3个文件,这种方式报错Plain Text code
ERROR/MediaPlayer(9974): start called in state 64
ERROR/MediaPlayer(9974): error (-38, 0)
ERROR/MediaPlayer(9974): Error (-38,0)
