private void UserControl_IsVisibleChanged(object sender, System.Windows.DependencyPropertyChangedEventArgs e)
{
if ((bool)e.NewValue == true && !listLoaded)
{
presenter.Token = Token;
presenter.Initialize();
ComboBoxUnit.ItemsSource = Units;
ComboBoxAgriculturalBrand.ItemsSource = AgriculturalBrands;
ComboBoxProductGroup.ItemsSource = ProductGroups;
listLoaded = true;
}
}