//EventHandler for showing local video in ui
        private void Peer_LocalI420FrameReady(I420AVideoFrame frame)
        {
            lock (localVideoLock)
            {
                if (!localVideoPlaying)
                {
                    localVideoPlaying = true;

                    // Capture the resolution into local variable useable from the lambda below
                    uint width  = frame.width;
                    uint height = frame.height;

                    // Defer UI-related work to the main UI thread
                    RunOnMainThread(() =>
                    {
                        // Bridge the local video track with the local media player UI
                        int framerate           = 30; // for lack of an actual value
                        localVideoSource        = CreateI420VideoStreamSource(width, height, framerate);
                        var localVideoPlayer    = new MediaPlayer();
                        localVideoPlayer.Source = MediaSource.CreateFromMediaStreamSource(localVideoSource);
                        Mpe_localVideo.SetMediaPlayer(localVideoPlayer);
                        localVideoPlayer.Play();
                    });
                }
            }
            localVideoBridge.HandleIncomingVideoFrame(frame);
        }
        //Suspending-EventHandler of app: executes when app turns into suspending-state
        private void App_Suspending(object sender, SuspendingEventArgs e)
        {
            if (peerConnection != null)
            {
                //Closing of PeerConnection
                peerConnection.Close();
                //Disposing of PeerConnection-Resources
                peerConnection.Dispose();
                peerConnection = null;

                Debugger.Log(0, "", "Peer conection disposed successfully\n");
            }

            //Disposing of MediaPlayers
            Mpe_localVideo.SetMediaPlayer(null);
            Mpe_remoteVideo.SetMediaPlayer(null);

            //Disposing of signaler
            if (signaler != null)
            {
                signaler.StopPollingAsync();
                signaler = null;
            }
        }