wxpython dialog - do something after ShowModal()?

[Iain King]

Hi.  I have a modal dialog whcih has a "Browse..." button which pops
up a file selector.  This all works fine, but the first thing the user
has to do when they open the dialog is select a file, so I would like
the dialog to automatically call the onBrowse function as soon as the
dialog opens.  However, I don't know how to do this.

dlg.ShowModal()
onBrowse()

obviously doesn't work, and neither does the reverse.  I was hoping
that the dialog would throw some kind of "I have been shown" event,
but it doesn't (as far as I can tell).  How do I make the dialog do
something as soon as it's been shown?

Iain