Question

I use a TabControl
Each tab has its default button.
The first default button is working.
The second default button is a normal button.
How to fix that?

Answer 1

You could bind each Button’s IsDefault property to its corresponding TabItem’s IsSelected Property. Each time the selected tab item changes, another button would become the default, then.

Something like that:

<TabControl>
  <TabItem x:Name="tab1" ... />
  <!-- ... other tabs ... -->
</TabControl>
<Button x:Name="button1" IsDefault="{Binding IsSelected, ElementName=tab1}"/>
<!-- ... other buttons ... -->