private void App_BackRequested(object sender, BackRequestedEventArgs e)
        {
            // Navigate back if possible, and if the event has not
            // already been handled .

            HideMessageMenu.Begin();
            MessageMenu.Margin         = new Thickness(100000, 0, 0, 0);
            HideMessageMenu.Completed += HideMessageMenu_Completed1;
        }
        private void Backbtn_Tapped(object sender, TappedRoutedEventArgs e)
        {
            HideMessageMenu.Begin();
            HideMessageMenu.Completed += HideMessageMenu_Completed;

            if (h == 1)
            {
                MessageMenu.Visibility = Visibility.Collapsed;
            }

            MainMenu.Visibility = Visibility.Visible;
        }