In WPF, Binding Between a UserControl and an Application

Question

Hi,
I realize a WPF application under VS 2017 Community. I start in this technique. I added a UserControl to the solution and I integrated it into the application. But I can not achieve the binding of a UserControl object (Background) to the same property of an identical object of the main application.
In the application, there is a Border named "Feu" which must receive the Border Background also named "Feu" which is located in the UserControl.
Who can help me ? thank you very much
Here is the source code of solution.

Henriot · Answer

I'm sorry my explanations are confusing. My bad English is certainly the cause and I apologize for not writing it better. So I start in WPF and maybe my vision of its possibilities is wrong ... But you are very kind to help me. To make you understand better my idea, I realized this little simulator in WinForm that I mastered better. The important thing is not to see how he works but especially what he does. The Control (My UserControl) has an F1 indicator. A mouse click on this F1 causes its color change, which is reflected on the F2 indicator of the main application. Obviously, in the reality of my application, it is an event internal to Control that causes the color change of F1 indicator. It is this mechanism that I want to realize in WPF where F1 (in UserControl) and F2 (in application) are defined as two Border  elements, only by Binding from the Background of F1 to the Background of F2 . Is it clearer now? Thank You  Best regards

Henriot · Answer

Thank you Piyush for your very quick answer. But that's not quite it. The UserControl has its own management. It contains a Border element named Feu whose Background changes color under the Mouse-Up action of the mouse placed on it. OK. The UserControl is added to the main app as SrcFeu " ...>. OK.   The main app also has a Border named Feu that must take the color of the Feu that is in the UserControl (SrcFeu). A change in the Color of the UserControl Feu must cause the change of color of the Feu of the main app . In your last proposal: The UserControl Feu is managed by the main app (Mouse_Up) It's all the background of the UserControl that is returned in the Feu app, not that of his Border Feu. I think it's possible to link only the properties of the UserControl with the main app. But I do not know how to do that. Do you know how to do it ?   Best regards

Piyush Pansuriya · Answer

Hi, I don't understand what you want to do, but i have made changes as I understand till. Please check attachment

Henriot · Answer

Thank you Piyush for your answer and the correction you made in the code. But, what I want to achieve is control the "Feu" of the application by that of the UserControl, as indicated on the attached screenshot. I do not know how to use a UserControl since the application. Can you help me in this case?   Thank you

Piyush Pansuriya · Answer

Hi, Have Done Changes in your code. Please check attachment, is it fulfill your requirement or not?