I am trying to switch a UserControl from using the RadToolTip to using the RadToolTipManager with load on demand. I had the page working with the regular tooltip, but now it pops up the tooltip window, but it is just blank (the on demand control never shows).
I can set break points and see that the control loads, and the properties are being set, but the preRender event never fires (I don't know if needs to in this case).
Anyway, I don't get any errors, the control just doesn't display. I must be doing something stupid, but I can't figure out what it is.
Here is the ascx code:
Width="360" Height="288" Animation="Slide"
Position="MiddleRight" Sticky="true" AutoCloseDelay="1000"
Here is the .vb code
Protected Sub OnAjaxUpdate(ByVal sender As Object, ByVal args As ToolTipUpdateEventArgs)
Private Sub UpdateToolTip(ByVal contextKey As String, ByVal panel As UpdatePanel)
If contextKey = "" Then Exit Sub
Dim ctrl As Control = Page.LoadControl("~/App_WebUserControls/bpThumbnail.ascx")
Dim bigThumbnail As App_WebUserControls_bpThumbnail = DirectCast(ctrl, App_WebUserControls_bpThumbnail)
bigThumbnail.AltText = contextKey