Dialog box with exit?

Anvil Q&A
4

In that particular app, the alert is in a while loop:

  while anvil.users.get_user() is None:
    choice = anvil.alert(d, title="Log In", dismissible=True, buttons=BUTTONS)

Unless the user logs in with the alert, anvil.users.get_user() will be None, and so the loop will continue, and the alert will be continously re-created.

At the end of the loop, there is:

    elif choice is None and allow_cancel:
      break

So if you want to simply break out of the loop if the alert is dismissed, set allow_cancel=True.