Callback Delegate on UI thread?

Hi !

Ok below is the code which uses a delegate and also specify's a callback sub
now the callback sub should be on UI Thread if that is true then why does the below code do not work and it also does not give any kind of error

I have been struggling with delegates
any help would be greatly appreciated

Delegate Function dlg() As Boolean

Dim tvDlg As New dlg(AddressOf updatetv)

Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load

    ' Passed the delegate into the BeginInvoke so it can be retrieved later.
    tvDlg.BeginInvoke(New AsyncCallback(AddressOf updatecomplete), tvDlg)

End Sub

Function updatetv() As Boolean
    Try
        ' TreeView1.Nodes.Add("ok")
        'if i uncommnet the above line it will give a error that on a wrong thread , ok that is fine i understand that
        Return True
    Catch ex As Exception
        Debug.WriteLine(ex.Message)
    End Try
End Function

Sub updatecomplete(ByVal ar As IAsyncResult)
    Dim oDel As dlg
    Dim bResult As Boolean
    Dim objResult As AsyncResult

    ' Extract the delegate from the AsyncResult
    objResult = CType(ar, AsyncResult)
    oDel = objResult.AsyncDelegate

    ' Obtain the result
    bResult = oDel.EndInvoke(ar)

    ' now this function is not wokring also there is no error
    w()
End Sub

Function w()
    TreeView1.Nodes.Add ("ok")
    Debug.WriteLine("done")
End Function

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Callback Delegate on UI thread?

bfellner
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Callback Delegate on UI thread?

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