private void SwitchVideo_MouseLeftButtonDown(object sender, MouseButtonEventArgs e)
 {
     CallController.Instance.Switch2VideoMode();
     EventSwitch2VideoMode?.Invoke();
 }
 private void SwitchVideo_Click(object sender, RoutedEventArgs e)
 {
     CallController.Instance.Switch2VideoMode();
     EventSwitch2VideoMode?.Invoke();
 }