namespace AppKit
{
    [Register("NSPopUpButton", true)]
    [SupportedOSPlatform("macos")]
    [UnsupportedOSPlatform("maccatalyst")]
    public class NSPopUpButton : NSButton
    {
        public static class Notifications
        {
            public static NSObject! ObserveWillPopUp(NSObject! objectToObserve, EventHandler<NSNotificationEventArgs!>! handler);
        }
    }
}