Is there any event when a submenu (in a popupmenu) is opened?
I have a very large menu with multiple levels kind of like a file system, so I do not want to create the entire menu at once. Rather when the user opens one submenu/directory, it should initialize that submenu and then the next one only when the user opens another directory.
On GTK it works with OnClick on the directory menuitem, but it does not seem to work on Windows