Unable to get currect interact between Racket threads and Gtk main loop

[zhaose233]

I want to change the widgets in a racket thread, but after 3 seconds nothing happens, after a very long time ( randomly ), it works. Then I tried to use GLib.iddel_add to interact with the main loop, the type of Racket function is not a so it throws an error. But even the error happens a long time after 3 seconds.