Question about ViewModel Management (DesignTime Vs Run Time)

Question

I have a fairly basic WPF UI whereby user requests cause a new tab to open in my TabControl. The TabControl is bound to an ObservableCollection

Answer 1

There is an easier way to do this. Have a DesignTimeUserAdministrationViewModel and populate it with static data in the constructor and refer that in UserControl as:

This way you have a design time test data bound to d:DataContext and runtime live data bound to the actual DataContext. More details here.