Android多媒体大冒险：MediaPlayer虚拟方法调用的神秘Bug

一、目前还不知道原因，只能记录下出现问题的过程和解决方法。

二、功能需求：使用mediaplayer加SurfaceView播放本地视频。

三、首先是真机测试，刚刚升级成Android 10，下面是配置：

四、使用mediaplayer播放手机目录下的一个视频。

视频地址：

//private static String mPath = Environment.getExternalStorageDirectory().getPath();
private static String mPath_ = "/storage/emulated/0/test.mp4";

mediaplayer加载方式：

1.mMediaPlayer.setDataSource(path);//失败
2.mMediaPlayer.setDataSource(MainActivity.this,uri);//失败
3.mMediaPlayer = MediaPlayer.create(MainActivity.this,uri);//成功

试过好多加载方法，最后只有第三种成功了。

五、报错：

2020-06-19 19:52:50.276 31343-31343/com.likego.audiofocusdemo W/MediaPlayer: Couldn't open /storage/emulated/0/test.mp4
    java.io.FileNotFoundException: No content provider: /storage/emulated/0/test.mp4
        at android.content.ContentResolver.openTypedAssetFileDescriptor(ContentResolver.java:1700)
        at android.content.ContentResolver.openAssetFileDescriptor(ContentResolver.java:1530)
        at android.content.ContentResolver.openAssetFileDescriptor(ContentResolver.java:1447)
        at android.media.MediaPlayer.attemptDataSource(MediaPlayer.java:1105)
        at android.media.MediaPlayer.setDataSource(MediaPlayer.java:1077)
        at android.media.MediaPlayer.setDataSource(MediaPlayer.java:1005)
        at android.media.MediaPlayer.create(MediaPlayer.java:912)
        at android.media.MediaPlayer.create(MediaPlayer.java:889)
        at android.media.MediaPlayer.create(MediaPlayer.java:868)
        at com.likego.audiofocusdemo.MainActivity.play(MainActivity.java:84)
        at com.likego.audiofocusdemo.MainActivity.access$000(MainActivity.java:29)
        at com.likego.audiofocusdemo.MainActivity$1.surfaceCreated(MainActivity.java:67)
        at android.view.SurfaceView.updateSurface(SurfaceView.java:943)
        at android.view.SurfaceView.lambda$new$0$SurfaceView(SurfaceView.java:150)
        at android.view.-$$Lambda$SurfaceView$w68OV7dB_zKVNsA-r0IrAUtyWas.onPreDraw(Unknown Source:2)
        at android.view.ViewTreeObserver.dispatchOnPreDraw(ViewTreeObserver.java:1088)
        at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:3097)
        at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:2008)
        at android.view.ViewRootImpl$TraversalRun