private static void OnSelectedItemChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
SpriteCategoryComboBox control = (SpriteCategoryComboBox)d;
if (control.supressEvents)
{
return;
}
control.supressEvents = true;
string propName = string.Empty;
if (control.GetBindingExpression(ItemsSourceProperty) != null)
{
propName = control.GetBindingExpression(ItemsSourceProperty).ResolvedSourcePropertyName;
}
if (control.ItemsSource != null)
{
Console.WriteLine($"{propName} SelectedItem Changed: Coerce");
control.SelectedItemBinding = (ComboItem)OnCoerceSelectedItem(control, control.SelectedItemBinding);
}
else
{
Console.WriteLine($"{propName} SelectedItem Changed: null");
control.SelectedItemBinding = null;
}
control.SelectedItemBinding = control.SelectedItem;
control.supressEvents = false;
}
private static object OnCoerceSelectedItem(DependencyObject d, object baseValue)
{
SpriteCategoryComboBox control = (SpriteCategoryComboBox)d;
/*ComboItem item = (ComboItem) baseValue;
* if (item == null || !control.ItemsSource.Items.Contains(item)) {
* if (control.ItemsSource == null)
* return null;
* else
* return ((ComboItem) control.ItemsSource).Items.FirstOrDefault();
* }
* else {
* return baseValue;
* }*/
string propName = string.Empty;
if (control.GetBindingExpression(SelectedItemProperty) != null)
{
propName = control.GetBindingExpression(SelectedItemProperty).ResolvedSourcePropertyName;
}
ComboItem item = (ComboItem)baseValue;
ComboItem source = control.ItemsSource;
if (source == null)
{
Console.WriteLine($"{propName} Coerce: null");
return(null);
}
else if (item != null && source.Items.Contains(item))
{
Console.WriteLine($"{propName} Coerce: Find");
return(source.Items.First(i => i.Id == item.Id));
}
Console.WriteLine($"{propName} Coerce: FirstOrDefault");
return(source.Items.FirstOrDefault());
}