wpf create a style for a custom control

Question

I have a custom control that inherits from another (third party) control:

public class Int32EditBox : Xceed.Wpf.Toolkit.IntegerUpDown { }

Then, I tried to create a style for this control:

xmlns:Controls="clr-namespace:MyApp.Controls;assembly=MyApp.Controls"
...     
<Style TargetType="{x:Type Controls:Int32EditBox}" BasedOn="{StaticResource {x:Type Controls:Int32EditBox}}">
            <Setter Property="ContextMenu" Value="{StaticResource DefaultDesignerContextMenu}" />
            <Setter Property="IsReadOnly" Value="True" />
          </Style>

The problem is that I get an error that says the resource "MyApp.Control.Int32EditBox" cannot be found.

Does anybody know why I'm getting this error?

Answer 1

Add this to the static constructor of your custom control, otherwise it will use the style for Xceed.Wpf.Toolkit.IntegerUpDown or whatever base class has set the default style key:

static Int32EditBox()
{
    DefaultStyleKeyProperty.OverrideMetadata(typeof(Int32EditBox), new FrameworkPropertyMetadata(typeof(Int32EditBox)));
}

And in order for the BasedOn to work, there must be another style with that key within the visual tree.