private void btnLanguagesSettings_Click(object sender, RoutedEventArgs e)
        {
            if (this.cbLanguages.SelectedIndex > -1)
            {
                int           index   = cbLanguages.SelectedIndex;
                LanguagesForm setting = new LanguagesForm(true, index);

                setting.ShowDialog();

                if (setting.DialogResult.HasValue && setting.DialogResult.Value)
                {
                    this.RefreshLanguageList();

                    this.cbLanguages.SelectedIndex = index;
                }
            }
        }
        private void btnLanguagesAdd_Click(object sender, RoutedEventArgs e)
        {
            if (this.cbPages.SelectedIndex > -1)
            {
                LanguagesForm add = new LanguagesForm();

                add.ShowDialog();

                if (add.DialogResult.HasValue && add.DialogResult.Value)
                {
                    RefreshLanguageList();
                }

                this.cbLanguages.SelectedIndex = this.cbLanguages.Items.Count - 1;
            }
            else
            {
                showPageNotSelectedError();
            }
        }