private void WriteMessageText(string message, bool overwrite = false)
 {
     messageDispatcher.InvokeAsync(Windows.UI.Core.CoreDispatcherPriority.Normal,
                                   (s, a) =>
     {
         if (overwrite)
         {
             MessageBlock.Text = message;
         }
         else
         {
             MessageBlock.Text += message;
         }
     }, this, null);
 }