Wpf – Have a databound WPF Listbox generate subclassed ListboxItems

data-bindinglistboxsubclasswpf

I would like to have my WPF Listbox, which is databound, generate subclassed ListboxItems instead of the regular ListboxItems. In this case, a DataTemplate is not sufficient because I need some custom properties for the subclassed ListBoxItems.

Is there a way to have the ListBox generated mySubClassedListBoxItem items for the bound data?

Thanks,
Bart

Best Answer

You need to create your own subclass of ListBox so you can override the method which creates the container, e.g.

public class MyListBox : ListBox
{
    public MyListBox()
    {
        // Should get the default style & template since styles are not inherited
        Style = FindResource(typeof(ListBox)) as Style;
    }

    protected override DependencyObject GetContainerForItemOverride()
    {
        var container = new MyListBoxItem();
        return container;
    }
}

public class MyListBoxItem : ListBoxItem
{
    public MyListBoxItem()
    {
        Style = FindResource(typeof(ListBoxItem)) as Style;
        // To easily see that these are custom ListBoxItems:
        // TextElement.SetForeground(this, Brushes.Red);
    }

    // ...
}