Hide the root window when a Toplevel window is opened and make it reappear when the Toplevel is destroyed

Question

How can I hide the MAIN window when the SECOND window is opened and then make the MAIN window reappear when the SECOND window is closed?

I understand the use of withdraw

Answer 1

You can put a binding on <Destroy> of the second window which will call a function that will call deiconify on the master.

This would be easier in your code if Second was a subclass of Toplevel. If you did that, you could hide this code inside the definition of Second. For example:

...
def Open(self):
    second_window = Second(self.master)
...

class Second(Toplevel):

    def __init__(self, master):
        Toplevel.__init__(self, master)
        self.master = master
        self.master.withdraw()
        self.bind("<Destroy>", self.on_destroy)

    def on_destroy(self, event):
        if event.widget == self:
            self.master.deiconify()