ComboBox ItemTemplate only working in dropdown

Question

I am trying to show a ComboBox whose ItemsSource is a collection of Controls (it is part of a PropertyGrid, the ComboBox should display the names of the controls, and the us

Answer 1

The ComboBox, for some very complex reasons exposes a read-only property called SelectionBoxItem. The content presenter in the ComboBox template binds on this property. It is the SelectionBoxItem that exposes the string representation of non-UI elements allowing you to see the selected value. The use of this property is what prevents the content presenter from using data templates. This is why the template applies to the drop down but not the selected item. Here is the part of the default ComboBox template causing the issue:

You can however create your own ComboBox style that overrides the default ContentPresenter and uses the SelectedItem instead of SelectionBoxItem and ItemTemplate instead of SelectionItemBoxTemplate. This will resolve the issue.