private static void OnItemsSourceChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
ComboItemComboBox control = (ComboItemComboBox)d;
if (e.NewValue != null)
{
d.CoerceValue(SelectedItemProperty);
}
}
private static object OnCoerceSelectedItem(DependencyObject d, object baseValue)
{
ComboItemComboBox control = (ComboItemComboBox)d;
ComboItem item = (ComboItem)baseValue;
if (item == null)
{
if (control.ItemsSource == null)
{
return(null);
}
else
{
return(((IEnumerable <ComboItem>)control.ItemsSource).FirstOrDefault());
}
}
else
{
return(baseValue);
}
}