Android preload VideoViews in AsyncTask

Question

I'm searching for a solution to preload some videos from different urls into VideoViews, so that they could be played without any delay. I'm trying to do this in an async task:

class VideoPreloadTask extends AsyncTask<String, Void, Void> {

    private Context mContext;
    private CustomVideoView mVideoView;

    public VideoPreloadTask(Context context) {
        mContext = context;
    }

    @Override
    public void onPreExecute() {
        mVideoView = new CustomVideoView(mContext);
    }


    @Override
    protected Void doInBackground(String... params) {
        final String url = params[0];

        mVideoView.setVideoPath(url);
        mVideoView.setOnPreparedListener(new OnPreparedListener() {

            //Wird aufgerufen, wenn das Video fertig geladen ist
            @Override
            public void onPrepared(MediaPlayer mp) {

                mCounter++;
                mVideoView.pause();
                mVideoView.setPreloaded(true);

                //Fuege das fertig geladene Video der Liste hinzu
                mVideos.put(url, mVideoView);
            }
        });

        mVideoView.start();

        return null;
    }
}

Now within the doInBackground-Method I set the path Url and start the loading of the video with start(). But the onPrepare-Listener does not work. The function never gets called and I don't understand why. I've tried loading some videos outside of an async task and it works well.

The async tasks are started like this:

for(String url : videoUrls) {
        VideoPreloadTask task = new VideoPreloadTask(context);
        task.execute(url);
    }

and my CustomVideoView-Class looks like the following:

public class CustomVideoView extends VideoView {

private boolean mPreloaded = false;
private String mPath = "";

public CustomVideoView(final Context context) {
    super(context);
}

public CustomVideoView(final Context context, final AttributeSet set) {
    super(context, set);
}

@Override
public void setVideoPath(String url) {
    super.setVideoPath(url);
    mPath = url; 
}

public boolean isPreloaded() {
    return mPreloaded;
}

public void setPreloaded(boolean isPreloaded) {
    mPreloaded = isPreloaded;
}

public String getVideoPath() {
    return mPath;
}

}

Does anybody know, what causes this behaviour or where I've made a mistake?

Answer 1

Finally solved my problem. For everyone whos interested, heres the answer:

It seems as if Android only preloads the VideoViews video, when the view is part of an XML-Layout, which is also currently active. So if you want to preload a video, make the videoview part of your xml and do not create a videoview-object with the constructor, as I've done it. Then it should work! :D