[Fxruby-users] creating an error message without showing main window

[Joel V. <vj...@PA...>]

I just realized how easy this is to do, so here is for posterity (i.e., 
so I can google it when I forget how to do it :) The trick is to avoid 
app.run (which would never terminate by itself because win.show never 
happened, so there's nothing to close). Apologies if this is common 
knowledge...

require 'fox'
include Fox

app = FXApp.new
win = FXMainWindow.new(app, "")

app.create

FXMessageBox.error(win, MBOX_OK, "caption", "message")