Example of using a delegate in wpf forms to pass a paramater from a child to sub in parent

Question

Hi
Looking for a example or explanation of how to use delegate to pass a parameter from a wpf form child to a sub in the parent to be executed in vb.net.
Thanks

Answer 1

Hi Paul
As trying to use a delegate as declaring and referencing along the lines of  
https://msdn.microsoft.com/query/dev12.query?appId=Dev12IDEF1&l=EN-US&k=k(vb.Delegate);k(SolutionItemsProject);k(TargetFrameworkMoniker-.NETFramework,Version%3Dv4.5);k(DevLang-VB)&rd=true
Thanks
RB_IA
My experience with using delegates is related to Multi-threading or otherwise accessing members/methods running on separate threads.
A WPF example of that would be something like this:
Option Strict On
Option Explicit On
Option Infer Off
Class MainWindow
Delegate Sub dSetTitle(window As Window, text As String)
Dim dispatched As Boolean = False
Private Sub btnSafeCall_Click(sender As Object, e As RoutedEventArgs) Handles btnSafeCall.Click
Dim th As New System.Threading.Thread(AddressOf SafeThread)
th.Start()
End Sub
Private Sub btnUnsafeCall1_Click(sender As Object, e As RoutedEventArgs) Handles btnUnsafeCall1.Click
Dim th As New System.Threading.Thread(AddressOf UnsafeThread)
th.Start()
End Sub
Sub SetTitle(window As Window, text As String)
If Not dispatched Then
dispatched = True
Dispatcher.Invoke(New dSetTitle(AddressOf SetTitle), window, text)
Else
dispatched = False
window.Title = text
End If
End Sub
Sub SafeThread()
SetTitle(Me, "test2")
End Sub
Sub UnsafeThread()
Me.Title = "test"
End Sub
End Class
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