Bind Dependency Property, defined in Code-Behind, through Xaml to a Property in the DataContext of a UserControl

Question

I want to use code similar to that found here. The issue I'm having is that I'd like to extend it to allow the value set in the XAML to use {Binding PropertyOfViewModel} like this:


  
    {Binding PropertyOfViewModel}

The problem, is that it errors with "Cannot Convert "{Binding PropertyOfViewModel}"". The TestObject property is defined as a dependency property in the code-behind of the view.

If I can get it to work, this will allow me to write code like this in the parent control:

Which means in the UserControl I can also bind to commands and other items exposed in my TCViewModel, and the control can be mostly self-contained, and all a consumer need to is set the DataContext property.

edit

This is the entire control:

In order to get it to compile with the code suggested, I had to re-arrange my xaml, now it both crashes Visual Studio in Design Mode, and when I run it, I get a StackOverflow exception on InitializeComponent(); in the Views Constructor.

edit 2

This is the code that puts this UserControl on the window:

Interestingly: if I remove this code from the Window, it runs/compiles OK. If I remove all of the type code from within the View, it also runs OK. But does not do what I want because I cannot bind my DP to the DataContext.

If I change the UserControl to the below, everything compiles fine, I just loose the binding on my code-behind dependency property:

Code-Behind Dependency Property:

    public bool IsInAcceptDataMode
    {
        get { return (bool)GetValue(IsInAcceptDataModeProperty); }
        set 
        {
            SetValue(IsInAcceptDataModeProperty, value); 

            if (value)
            {
                VisualStateManager.GoToState(this, "Show", false);
            }
            else
            {
                VisualStateManager.GoToState(this, "Hide", false);
            }
        }
    }

    public static readonly DependencyProperty IsInAcceptDataModeProperty =
        DependencyProperty.Register("IsInAcceptDataMode", typeof(bool), typeof(AddClientView), new UIPropertyMetadata(false, null));

edit 3

So I've been informed that there are issues with XAML based binding, I tried moving to code-behind, and I still cannot get it to work. So, I'm looking at this point for a code-behind based way to bind my DependencyProperty to an item in the ViewModel which is specified to the DataContext of my UserControl.

Pavlo Glazkov · Accepted Answer

If I understood everything correctly then what you need is a standard MVVM scenario and standard bindings.

It can be done either like this:

Or like this:

Update: In response to the code of your UserControl you've shown...

What you are doing is placing a control inside itself, which obviously will give you a StackOverflow exception. You don't need to define a ContentTemplate inside UserControl. You can just place the content directly as a child element:

Bind Dependency Property, defined in Code-Behind, through Xaml to a Property in the DataContext of a UserControl

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