NavigationViewHeaderBehaviour does not work correctly when setting HeaderContext to Page

[sibille]

Raising a separate issue for this (X-Ref:#1229)

We're facing an issue in the NavViewHeaderBehaviour with CodeBehind.
X:Bind is not working in the DataTemplate when HeaderContext is set to a Page.

Possible workarounds would be:

• Bind to a HelperClass
• Not setting HeaderContext and use binding instead of x:bind.

I've attached a solution where you can see the problem and the workaround:
App1.zip

• App1_XBind_Page: This project shows the problem, binding seems to work fine, but value is not shown.
• App1_XBind_Helper: Solution 1: Bind to a HelperClass
• App1_Binding: Solution 2: Use Binding instead of xBind
• App1_ContentPresenter: This project shows what we suspect is the underlying problem, a ContentPresenter with Content bound to a page does not resolve bindings in ContentTemplate correctly, a ContentPresenter with content bound to another class does.

[sibille]

Moving to 3.0 to revisit once problem is solved on the control

[crutkas]

pushing to 3.1 / hot fix depending on WinUI

[sibille]

Looking into this with the WinUI team we think the best solution is using binding for the CodeBehind design pattern.