MediaPlayer.prepare() throws IllegalStateException on Android L

问题:

I have code that plays mp3 file from assets directory:

MediaPlayer mediaPlayer = new MediaPlayer(); descriptor = context.getAssets().openFd("beep.mp3"); mediaPlayer.setDataSource(descriptor.getFileDescriptor(), descriptor.getStartOffset(), descriptor.getLength()); mediaPlayer.setAudioStreamType(AudioManager.STREAM_MUSIC); mediaPlayer.setVolume(soundLevel, soundLevel); descriptor.close(); mediaPlayer.setLooping(false); mediaPlayer.prepare(); mediaPlayer.start(); 

This code was working fine on every device and every Android version. Until after Android L preview came available. mediaPlayer.prepare();throws IllegalStateException on Nexus 5 running Android L.

Emulator version of Android L works completely fine, I don't own Nexus 5 so can't say what exactly is causing the issue. I am thinking about descriptor.close() line before prepare() called, but not sure.

回答1:

public void myBeep() {     try {         if (m.isPlaying()) {             m.stop();             m.release();             m = new MediaPlayer();         }          AssetFileDescriptor descriptor = getAssets().openFd("beep.mp3");         m.setDataSource(descriptor.getFileDescriptor(), descriptor.getStartOffset(), descriptor.getLength());         descriptor.close();          m.prepare();         m.setVolume(1f, 1f);         m.setLooping(true);         m.start();     } catch (Exception e) {         e.printStackTrace();     } }; 

文章来源: MediaPlayer.prepare() throws IllegalStateException on Android L