Crash en MediaController.show ()

Tengo un problema con mediacontroller, esta parte del código funciona perfectamente en diferentes dispositivos como Acer Liquid (pan de jengibre), Archos 43 (froyo) y Archos 32 (froyo) …

VideoView videoView = (VideoView) findViewById(R.id.videoView1); MediaController mediaController = new MediaController(this); mediaController.setAnchorView(videoView); File filevideo = new File(Environment.getExternalStorageDirectory() + "/edizionitsm/firenze/map_" + map_n + "/",filename + "_" + language + ".mp4"); Uri video = Uri.fromFile(filevideo); videoView.setMediaController(mediaController); videoView.setVideoURI(video); videoView.start(); 

… pero en un punto de vista Pro Tab2 (pan de jengibre) se bloquea al inicio de la actividad.

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 11-09 14:12:59.640: E/AndroidRuntime(31433): FATAL EXCEPTION: main 11-09 14:12:59.640: E/AndroidRuntime(31433): java.lang.RuntimeException: Unable to start activity ComponentInfo{edizionitsm.archeoplayer/edizionitsm.archeoplayer.Player}: java.lang.NullPointerException 11-09 14:12:59.640: E/AndroidRuntime(31433): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1647) 11-09 14:12:59.640: E/AndroidRuntime(31433): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1663) 11-09 14:12:59.640: E/AndroidRuntime(31433): at android.app.ActivityThread.access$1500(ActivityThread.java:117) 11-09 14:12:59.640: E/AndroidRuntime(31433): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:931) 11-09 14:12:59.640: E/AndroidRuntime(31433): at android.os.Handler.dispatchMessage(Handler.java:99) 11-09 14:12:59.640: E/AndroidRuntime(31433): at android.os.Looper.loop(Looper.java:123) 11-09 14:12:59.640: E/AndroidRuntime(31433): at android.app.ActivityThread.main(ActivityThread.java:3683) 11-09 14:12:59.640: E/AndroidRuntime(31433): at java.lang.reflect.Method.invokeNative(Native Method) 11-09 14:12:59.640: E/AndroidRuntime(31433): at java.lang.reflect.Method.invoke(Method.java:507) 11-09 14:12:59.640: E/AndroidRuntime(31433): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:839) 11-09 14:12:59.640: E/AndroidRuntime(31433): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:597) 11-09 14:12:59.640: E/AndroidRuntime(31433): at dalvik.system.NativeStart.main(Native Method) 11-09 14:12:59.640: E/AndroidRuntime(31433): Caused by: java.lang.NullPointerException 11-09 14:12:59.640: E/AndroidRuntime(31433): at android.widget.MediaController.disableUnsupportedButtons(MediaController.java:640) 11-09 14:12:59.640: E/AndroidRuntime(31433): at android.widget.MediaController.show(MediaController.java:674) 11-09 14:12:59.640: E/AndroidRuntime(31433): at android.widget.MediaController.show(MediaController.java:631) 11-09 14:12:59.640: E/AndroidRuntime(31433): at android.widget.VideoView.start(VideoView.java:962) 11-09 14:12:59.640: E/AndroidRuntime(31433): at edizionitsm.archeoplayer.Player.onCreate(Player.java:48) 11-09 14:12:59.640: E/AndroidRuntime(31433): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047) 11-09 14:12:59.640: E/AndroidRuntime(31433): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1611) 11-09 14:12:59.640: E/AndroidRuntime(31433): ... 11 more 

el problema está en la función show () de la clase mediacontroller. ¿Cómo puedo resolverlo? Gracias.

 VideoView videoView = (VideoView) findViewById(R.id.videoView1); MediaController mediaController = new MediaController(this); mediaController.setAnchorView(videoView); mediaController.setMediaPlayer(videoView); File filevideo = new File(Environment.getExternalStorageDirectory() + "/edizionitsm/firenze/map_" + map_n + "/",filename + "_" + language + ".mp4"); Uri video = Uri.fromFile(filevideo); videoView.setMediaController(mediaController); videoView.setVideoURI(video); videoView.start();