private void SignButton_OnClick(object sender, RoutedEventArgs e)
 {
     if (UserNameBox.Text == "Admin")
     {
         if (PasswordBox.Password == "Admin")
         {
             App.LoginStatus           = true;
             AdminItem.Visibility      = Visibility.Visible;
             MainSignButton.Visibility = Visibility.Collapsed;
             MainSignOut.Visibility    = Visibility.Visible;
             MyFlyOut.Hide();
         }
         else
         {
             ErorrMessage.Text    = "Wrong Password";
             PasswordBox.Password = "";
         }
     }
     else
     {
         ErorrMessage.Text    = "Wrong User name or Password";
         PasswordBox.Password = "";
         UserNameBox.Text     = "";
     }
     PasswordBox.Password = "";
     UserNameBox.Text     = "";
 }
 private void CancelButton_OnClick(object sender, RoutedEventArgs e)
 {
     MyFlyOut.Hide();
 }