Child windows are handled separately from the main window

#include <GUIConstantsEx.au3>$mainwindow= Guicreate ("Hello World", -, $) Guictrlcreatelabel ("Hello world!", -,Ten) $okbutton= Guictrlcreatebutton ("opened the subform", -, -, MaxThe main window clicks the button and creates a new subwindow, and the main window closes when the Subwindow is closed.
$dummywindow= Guicreate ("Dummy window for testing", $, -) Guiswitch ($mainwindow) guisetstate (@SW_SHOW) while1$msg= Guigetmsg (1) Select case $msg [0] =$okbutton guisetstate (@SW_SHOW, $dummywindow) Case $msg [0] = $GUI _event_close and $msg [1] =$mainwindow Exit case $msg [0] = $GUI _event_close and $msg [1] =$dummywindow guisetstate (@SW_HIDE, $dummywindow) endselectwend

Child windows are handled separately from the main window