android 用MyTV等第三方应用播放直播视频，只有声音没有画面

修改：

Frameworks\av\media\libmediaplayerservice\nuplayer\nuplayer.cpp

Void nuplayer::onMessageReceived(const sp<AMessage> &msg)  {

...

case kWhatSetVideoNativeWindow:

{

ALOGD("kWhatSetVideoNativeWindow");

//add

if(mAudioDecoder == NULL||mVideoDecoder == NULL)

postScanSources();

...

}

...

}