Is it possible to group items in a NSPopupButton?

Question

I'm trying to display a list of system voices, but I'd like to group them by region.

This is an example of select in html.

Ideally I'd like to create a dropdown that is similar to accessibility language selection.

Is there any way to replicate this in Interface Builder / swift? Any pointers would be appreciated.

Update:

The reason for this, is because I am displaying a list of speech voices to the user. At the moment, it mixes all the regions together, which is very confusing.

There is an update I'm working on, where I can display "English (United Kingdom)", but I'd like to group them up before releasing it.

Answer 1

The following code groups menu, but not like the way you mentioned.

let items = [["First","Second"],["First","Second"],["First","Second"]]

lazy var addNewViewButton : NSPopUpButton = {
    let popupButton = NSPopUpButton()

    let firstMenuItem = NSMenuItem(title: "First Group", action: nil, keyEquivalent: "")
    let secondMenuItem = NSMenuItem(title: "Second Group", action: nil, keyEquivalent: "")
    let thirdMenuItem = NSMenuItem(title: "Third Group", action: nil, keyEquivalent: "")

    let superMenu = NSMenu()
    superMenu.addItem(firstMenuItem)
    superMenu.addItem(secondMenuItem)
    superMenu.addItem(thirdMenuItem)

    for (index,item) in items.enumerated()
    {
        let menu = NSMenu()
        for title in item
        {
            let menuItem = NSMenuItem(title: title, action: nil, keyEquivalent: "")
            menuItem.target = self
            menu.addItem(menuItem)
        }
        menu.addItem(NSMenuItem.separator())
        superMenu.setSubmenu(menu, for: superMenu.items[index])
    }
    popupButton.menu = superMenu

    popupButton.translatesAutoresizingMaskIntoConstraints = false

    return popupButton
}()

Add the popupbutton in your code and you will get results like this

Each one will be having its own items inside.