Android MediaPlayer無法正常工作

Question

我寫了一個應用程序，當我按下按鈕時應播放聲音。但是，聲音幾乎每四次點擊一次，而不是全部。

@Override 
public void onClick(View v) { 
    if (v == bplus) { 
     vib.vibrate(100); 

     MediaPlayer mp = MediaPlayer.create(getBaseContext(), R.raw.beep); 

     mp.start(); 

     mp.setOnCompletionListener(new OnCompletionListener() { 

      @Override 
      public void onCompletion(MediaPlayer mp) { 
       // TODO Auto-generated method stub 
       mp.release(); 
      } 

     }); 

     counter++; 
    } 

當我使用mp.start前mp.prepare（）（）的聲音仍然是不規則的，我得到這個：

02-16 23:19:41.761: E/MediaPlayer(750): prepareAsync called in state 8 
02-16 23:19:41.761: W/System.err(750): java.lang.IllegalStateException 
02-16 23:19:41.771: W/System.err(750): at android.media.MediaPlayer.prepare(Native Method) 
02-16 23:19:41.781: W/System.err(750): at de.christianschmitz.counter.Starter.onClick(Starter.java:100) 
02-16 23:19:41.791: W/System.err(750): at android.view.View.performClick(View.java:3480) 
02-16 23:19:41.791: W/System.err(750): at android.view.View$PerformClick.run(View.java:13983) 
02-16 23:19:41.801: W/System.err(750): at android.os.Handler.handleCallback(Handler.java:605) 
02-16 23:19:41.801: W/System.err(750): at android.os.Handler.dispatchMessage(Handler.java:92) 
02-16 23:19:41.811: W/System.err(750): at android.os.Looper.loop(Looper.java:137) 
02-16 23:19:41.811: W/System.err(750): at android.app.ActivityThread.main(ActivityThread.java:4340) 
02-16 23:19:41.821: W/System.err(750): at java.lang.reflect.Method.invokeNative(Native Method) 
02-16 23:19:41.831: W/System.err(750): at java.lang.reflect.Method.invoke(Method.java:511) 
02-16 23:19:41.831: W/System.err(750): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:784) 
02-16 23:19:41.841: W/System.err(750): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:551) 
02-16 23:19:41.851: W/System.err(750): at dalvik.system.NativeStart.main(Native Method) 
02-16 23:19:41.851: E/MediaPlayer(750): error (-19, 0) 

Answer 1

你要了解更多關於MediaPlayer狀態圖

http://developer.android.com/reference/android/media/MediaPlayer.html