How to show Menu on button press instead of right mouse click in os x

Question

When I assign a Menu to a button, the menu will be shown when the user right click the button.

I want to open the menu when the user left click the button.

Something similar to this:

---

I got it working using this code, However the menu is shown at the top right corner of my screen. What am I doing wrong?

@IBOutlet var meeenu: NSMenu!
@IBAction func Options(sender: NSButtonCell) {
    meeenu.popUpMenuPositioningItem(meeenu.itemAtIndex(0), atLocation: NSEvent.mouseLocation(), inView: self.view)
}

Answer 1

I got it working finally using this code:

@IBOutlet var meeenu: NSMenu!
@IBAction func Options(sender: NSButtonCell) {
    meeenu.popUpMenuPositioningItem(meeenu.itemAtIndex(0), atLocation: NSEvent.mouseLocation(), inView: nil)
}