private void ButtonKindleToggle_Click(object sender, RoutedEventArgs e)
        {
            if (!kindleDisplayed)
            {
                kindleDisplayed = true;
                currentOnHold   = currentDisplay;

                this.Dispatcher.Invoke(new Action(() =>
                {
                    this.Cursor = Cursors.Wait;
                }));

                SetDisplayContent(KindleLibrarian.KindleObjects(currentDisplay));

                this.Dispatcher.Invoke(new Action(() =>
                {
                    this.Cursor = Cursors.Arrow;
                }));

                buttonKindleToggle.Background = ExTools.ConvertColorFromHexString(Constants.GreenClr);
            }
            else
            {
                kindleDisplayed = false;
                SetDisplayContent(currentOnHold);
                currentOnHold = null;
                buttonKindleToggle.Background = ExTools.ConvertColorFromHexString(Constants.RedClr);
            }
        }
        private void Grid_Loaded(object sender, RoutedEventArgs e)
        {
            Grid gd = (Grid)sender;

            var fic_id = gd.Tag.ToString();

            if (kindleIds.Contains(fic_id))
            {
                gd.Background = ExTools.ConvertColorFromHexString(Constants.GreenClr);
            }
        }