一、错误描述

刚用MediaPlayer播放Music的时候，看到Log打印台总是会打印一条错误日志，MediaPlayer: Should have subtitle controller already set，虽然程序运行不会出问题，但是看起来红色的日志很显眼，因此决定修改这个bug。具体的错误日志如下所示：

01-04 17:46:21.752 9395-9395/com.netease.xtc.cloudmusic I/CloudMusicPlayService: >>>>>>>>>>>>>>> mediaPlayer onBufferingUpdate
01-04 17:46:21.752 9395-9395/com.netease.xtc.cloudmusic D/MediaPlayer: handleMessage msg:(1, 0, 0)
01-04 17:46:21.753 9395-9395/com.netease.xtc.cloudmusic E/MediaPlayer: Should have subtitle controller already set
01-04 17:46:21.753 9395-9395/com.netease.xtc.cloudmusic I/CloudMusicPlayService: >>>>>>>>>>>>>>> mediaPlayer onPrepared
01-04 17:46:21.756 9395-9395/com.netease.xtc.cloudmusic I/CloudMusicPlayService: >>>>>>>>>>>>>>> startPlay

        

          
        
        
        

          

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二、错误解决

通过google，在stackoverflow网站上搜索到了答案，相关链接如下所示：
http://stackoverflow.com/questions/20087804/should-have-subtitle-controller-already-set-mediaplayer-error-android

解决方法一

忽略此警告Log，因为并不影响程序正常运行。

正如stackoverflow网站上的答案说说的

A developer recently added subtitle support to VideoView.

When the MediaPlayer starts playing a music (or other source), it checks if there is a SubtitleController and shows this message if it’s not set. It doesn’t seem to care about if the source you want to play is a music or video. Not sure why he did that.

Short answer: Don’t care about this “Exception”.

解决方法二

如果MediaPlayer仅仅是用于播放音频文件，并且你真的想消除这些错误log的打印，则参考下面的代码来获取MediaPlayer。

   /**
     *  博客地址： http://blog.csdn.net/ouyang_peng/
     * 获取MediaPlayer  修复bug ( MediaPlayer: Should have subtitle controller already set )
     * </br><a href = "http://stackoverflow.com/questions/20087804/should-have-subtitle-controller-already-set-mediaplayer-error-android/20149754#20149754">
     *     参考链接</a>
     *
     *  </br> This code is trying to do the following from the hidden API
     *   <p>
     * </br> SubtitleController sc = new SubtitleController(context, null, null);
     * </br> sc.mHandler = new Handler();
     * </br> mediaplayer.setSubtitleAnchor(sc, null)</p>
     */
    private MediaPlayer getMediaPlayer(Context context) {
        MediaPlayer mediaplayer = new MediaPlayer();
        if (android.os.Build.VERSION.SDK_INT < android.os.Build.VERSION_CODES.KITKAT) {
            return mediaplayer;
        }
        try {
            Class<?> cMediaTimeProvider = Class.forName("android.media.MediaTimeProvider");
            Class<?> cSubtitleController = Class.forName("android.media.SubtitleController");
            Class<?> iSubtitleControllerAnchor = Class.forName("android.media.SubtitleController$Anchor");
            Class<?> iSubtitleControllerListener = Class.forName("android.media.SubtitleController$Listener");
            Constructor constructor = cSubtitleController.getConstructor(
                    new Class[]{Context.class, cMediaTimeProvider, iSubtitleControllerListener});
            Object subtitleInstance = constructor.newInstance(context, null, null);
            Field f = cSubtitleController.getDeclaredField("mHandler");
            f.setAccessible(true);
            try {
                f.set(subtitleInstance, new Handler());
            } catch (IllegalAccessException e) {
                return mediaplayer;
            } finally {
                f.setAccessible(false);
            }
            Method setsubtitleanchor = mediaplayer.getClass().getMethod("setSubtitleAnchor",
                    cSubtitleController, iSubtitleControllerAnchor);
            setsubtitleanchor.invoke(mediaplayer, subtitleInstance, null);
        } catch (Exception e) {
            LogUtil.d(TAG,"getMediaPlayer crash ,exception = "+e);
        }
        return mediaplayer;
    }

        

          
        
        
        

          

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上面代码的作用是做类似于下面隐藏API的工作：

SubtitleController sc = new SubtitleController(context, null, null);
sc.mHandler = new Handler();
mediaplayer.setSubtitleAnchor(sc, null)

        

          
        
        
        

          

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然后将初始化MediaPlayer的代码由：

 MediaPlayer mediaPlayer = new MediaPlayer();

        

          
        
        
        

          

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改为：

MediaPlayer mediaPlayer = getMediaPlayer(this);

        

          
        
        
        

          

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然后重新运行APP之后就不会再出现之前的红色警告log MediaPlayer: Should have subtitle controller already set了。

作者：欧阳鹏 欢迎转载，与人分享是进步的源泉！
转载请保留原文地址：
http://blog.csdn.net/ouyang_peng/article/details/54023240