重写NSView的右键点击函数：
override func rightMouseDown(with event: NSEvent) {
let location = self.convert(event.locationInWindow, to: nil)
self.menu?.popUp(positioning: nil, at: location, in: self)
}
可以通过xib、代码等创建的NSMenu和自定义NSView的menu进行关联：
view.menu = rightMenu //rightMenu是作为右键事件弹出的菜单
