Custom Control Dependency Property Binding

Question

I am going insane trying to get this to work with even the most basic example. I cannot for the life of me get binding to work. Here is a super easy example that is not work

Answer 1

You haven't set the proper binding source. You would either have to set RelativeSource:

<Label Content="{Binding TestProp, RelativeSource={RelativeSource Mode=TemplatedParent}}" />

Or use TemplateBinding:

<Label Content="{TemplateBinding TestProp}"/>