Newbie: Invalid cross thread access with using busyindicator (silverlight and wcf service)
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I have a problem with the busyindicator control of silverlight.
I have a datagrid (datagrid1) with its source set to a wcf service (client).
I would like to use the busyindicator control (bi) of silvelright toolkit when the datagrid loads itself.

But I have an "Invalid cross thread access" when I use "ThreadPool".

    Sub LoadGrid()
            Dim caisse As Integer = ddl_caisse.SelectedValue
            Dim env As Integer = ddl_env.SelectedValue
    
            bi.IsBusy = True
            ThreadPool.QueueUserWorkItem(Sub(state)
                                             AddHandler client.Get_PosteSPTCompleted, AddressOf client_Get_PosteSPTCompleted
                                             client.Get_PosteSPTAsync(caisse, env)
                                             Dispatcher.BeginInvoke(Sub()
                                                                        bi.IsBusy = False
                                                                    End Sub)
                                         End Sub)
    End Sub
    
    Private Sub client_Get_PosteSPTCompleted(sender As Object, e As ServiceReference1.Get_PosteSPTCompletedEventArgs)
    	DataGrid1.ItemsSource = e.Result ' Here, Invalid cross thread access
    End Sub

I know that the datagrid control doesn't exist in the "new thread", but how have to I make to avoid this error?

Thank you.

William