java - Android MediaPlayer无法正常工作

Question

我编写了一个应在按下按钮时播放声音的应用程序。但是声音大约每四声一次播放一次，而不是全部播放一次。

@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++;
    }

当我在mp.start()之前使用mp.prepare()时，声音仍然不规则，我得到了以下信息:

    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

您必须了解有关MediaPlayer状态图的更多信息

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