public void LoadGameScene()
    {
        int enemies = InputFieldControl.getEnemiesNumber();

        if (enemies > 0)
        {
            SceneManager.LoadScene("MainScene");
        }
    }
 private static void OnRequiredChanged(DependencyObject d, DependencyPropertyChangedEventArgs e){
     InputFieldControl ctrl = d as InputFieldControl;
     // symbol is voided
     if ((bool)e.NewValue == false)
         ctrl.RequiredStringSymbol = string.Empty;
 }