ansaurus

Question

WPF + MVVM - Access object/property in UserControl

Answer 1

+1 A:

You can have the selected item be either a Dependency Property on your UserControl, or just be it's DataContext. You could then just setup the UserControl using binding:

<UserControl1 DataContext="{Binding TheSelectedObjectProperty}" />

If your list box binds to that same TheSelectedObjectProperty, the UserControl will see the selected item when you change items in the list box automatically.

Reed Copsey 2010-08-03 15:34:51

Thank you very much for the answer! I guess i should've been more specific, so i wouldnt waste your time, but: the thing is that the user control has its own viewmodel, and in the xaml of the usercontrol, the datacontext is set to that viewmodel. So i guess i cant set the datacontext again.I have tried to make the selected item a dependency property, but i couldnt make it work. I guess there is a possibility that i missed something when trying it though.Thank you!

MrZ 2010-08-03 16:11:43

Maybe i should also ask if it is possible to use binding with a relative source and findancestor to get the property?

MrZ 2010-08-03 16:13:28

@user409816: If you make the SelectedItem a dependency property, you should be able to setup the binding to it from teh "container" holding the UserControl. That will work fine.

Reed Copsey 2010-08-03 16:31:52

@user409816: This, btw, is effectively a master-detail scenario. I also wrote an article showing how to use Behaviors to accomplish this. It might be of use: http://reedcopsey.com/2009/10/14/using-a-behavior-to-aggregate-values-in-a-master-detail-view-in-m-v-vm/

Reed Copsey 2010-08-03 16:32:51

I'll definitely look in to this.. thank you very much for your help!

MrZ 2010-08-03 16:45:22

ansaurus

tags:

views:

answers:

WPF + MVVM - Access object/property in UserControl

related questions