This is the situation , you can test it for yourselves : The microsoft documentation specifies that when the initialized event is fired , all the properties are set (except bindings) If you create a new user control and in the code behind file you define a simple string property, then you put this new control on a page and set that property there , when the initialized event is fired on the user control that property will not be set. What is the workaround for this except for using the loaded event (cannot do that as I am only creating the controls in memory without displaying them.
Here is the code for the user control :
Public Class UserControl1
Private _Test As String
Public Property test() As String
Get
Return _Test
End Get
Set(ByVal v开发者_开发技巧alue As String)
_Test = value
End Set
End Property
Public Sub New()
' This call is required by the designer.
InitializeComponent()
' Add any initialization after the InitializeComponent() call.
End Sub
Protected Overrides Sub OnInitialized(ByVal e As System.EventArgs)
'MyBase.OnInitialized(e)
Debug.Write(_Test)
End Sub
Private Sub UserControl_Initialized(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Initialized
Dim parent As FrameworkElement = Me.Parent
parent = LogicalTreeHelper.GetParent(Me)
End Sub
End Class
I'm wondering why you comment out MyBase.OnInitialized(e)
?
What your trying to do is to set a property on a child element via XAML. I believe the MSDN article is saying that properties for the current UserControl (if set in XAML) will be set during the call to InitializeComponent.
InitializeComponent is called during the constructor of the UserControl. The parent element (your page) will have to create the UserControl, and therefore cause the constructor to run, before setting any properties on it.
If you want your child to be notified when a property is set, simply add code to that properties setter.
Another option may be to call a sub on the child after the parent has fully loaded.
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