Question

Possible Duplicate:
WPF: XAML property declarations not being set via Setters?

I am stuck on seemingly silly problem.

I have a user control, MyControl.xaml, and MyControl.xaml.cs defines a public dependency property:

public static readonly DependencyProperty VisibleItemsProperty =
    DependencyProperty.Register("VisibleItems", typeof(object), typeof(MyControl));

public object VisibleItems
{
    get { return (object)GetValue(VisibleItemsProperty); }
    set { SetValue(VisibleItemsProperty, value); }
}

Within another view SomeOtherViewA, i declare my control:

<cc:MyControl VisibleItems="{Binding VisibleTables}"  />

VisibleTables is a dependency property on the viewmodel SomeOtherViewModelA.

I know that VisibleTables returns values, because it is bound to other controls within SomeOtherViewA (such as ListBox) and they work fine.

For some reason the dependency property within my custom user control is never set. Am i missing something obvious?

Answer 1

I think i just found a duplicate.

Also more about this on MSDN:

The WPF XAML processor uses property
system methods for dependency
properties when loading binary XAML
and processing attributes that are
dependency properties. This
effectively bypasses the property
wrappers. When you implement custom
dependency properties, you must
account for this behavior and should
avoid placing any other code in your
property wrapper other than the
property system methods GetValue and
SetValue.

(SetValue is being called directly, those wrapper properties are just there for convenience in code behind)