Problem with raising event before the user leaves the page

Anvil Q&A
6

I guess it’s worth remembering you can do this all in python now


from anvil.js import window

class MyForm(MyFormTemplate):
    ...

    def handle_unload(self, e):
        if ...: # delete_proposal condition
            e.returnValue = ""
            e.preventDefault()
            # rest of the logic for delete_proposal
  
    # hook up form_show and form_hide events
    def form_show(self, **event_args):
        window.onbeforeunload = self.handle_unload

    def form_hide(self, **event_args):
        window.onbeforeunload = None
5 Likes