How to know, during design-time, which control is active / focused by the user in a custom items control, so as to show the rendering for that selected item?
I'm after functionality similar to TabControl. The difference in my control is that it displays a very simple, sequential workflow, with transitions in between, and will show breadcrumbs in place of tabs. I've tried extended the TabControl, but haven't gotten anything that works. Currently, I'm just displaying the first panel content of the control. I need to know when a developer has another panel active in the XAML editor to display content of that panel, accordingly.
I'm currently after a value that would be available in MeasureOverride, but would be flexible as long as I have anything available in the code-behind.I've tried such hacks as
panel.GotFocus += focusHandler;
but haven't met with any luck thus far.
The TabControl is obviously aware of which element is active at design-time. How is that known? Or, is there a styling I could apply to the TabControl that would change tabs to breadcrumbs and allow a transition between tab contents?