public static async Task <ContentDialogResult> SafeShowAsync(this ContentDialog cd)
 {
     using (var loc = await LockAsync.Create(ShowLockPoint))
     {
         return(await cd.ShowAsync());
     }
 }
 public static async Task <IUICommand> SafeShowAsync(this MessageDialog mb)
 {
     using (var loc = await LockAsync.Create(ShowLockPoint))
     {
         return(await mb.ShowAsync());
     }
 }