Silverlight dependency property not updating
But creating the enum with a value of –1 doesn’t work: This is why setting –1 to the default value of the dependency property doesn’t work (unless you of course have a –1 value in the enum!
So I have been using Dependency Properties on Templated Controls and had no issues...
In the following example, the custom class Public Class My State Control Inherits Button Base Public Sub New() My Base.
New() End Sub Public Property State() As Boolean Get Return CType(Me.
Receiving notifications for dependency property changes on an existing object is a very common scenario in order to update my view model or the UI.
Subsequent attempts to override metadata on the same type will raise an exception.
There, the UIProperty Meta Data can be used for Attached Properties and DPs.
I suggest leaving these untouched and creating new snippets named (for instance) slpropa and slpropdp.
The control just changes background color when you set the enum to On (green), or Off (red). The problem is that the dependency property will take the enum member with number 0 as default, On Off. And when setting the value in XAML (or code for that matter) will not update the property backing the dependency property: The code to render this is found here: As you can see the left one is NOT green. On (value 0), and setting it (again) to On doesn’t trigger the execution of On Property Changed Callback.
We can solve this (of course, otherwise what would be the point of writing this?
Calls to Override Metadata must be performed within the static constructors of the type that provides itself as the parameter of Override Metadata.