Cocoa Button that will light up with mouse over

Setup a tracking area for the view with addTrackingArea (provided you are using Leopard or newer OS X). You'll get events on mouse enter and mouse exit.

something below maybe the answer.

class HoverButton: NSButton{

var backgroundColor: NSColor?
var hoveredBackgroundColor: NSColor?
var pressedBackgroundColor: NSColor?

private var hovered: Bool = false

override var wantsUpdateLayer:Bool{
    return true
}

required init?(coder: NSCoder) {
    super.init(coder: coder)
    self.commonInit()
}

override init(frame frameRect: NSRect) {
    super.init(frame: frameRect)
    self.commonInit()
}

func commonInit(){
    self.wantsLayer = true
    self.createTrackingArea()
    self.hovered = false
    self.hoveredBackgroundColor = NSColor.selectedTextBackgroundColor()
    self.pressedBackgroundColor = NSColor.selectedTextBackgroundColor()
    self.backgroundColor = NSColor.clearColor()
}

private var trackingArea: NSTrackingArea!
func createTrackingArea(){
    if(self.trackingArea != nil){
        self.removeTrackingArea(self.trackingArea!)
    }
    let circleRect = self.bounds
    let flag = NSTrackingAreaOptions.MouseEnteredAndExited.rawValue + NSTrackingAreaOptions.ActiveInActiveApp.rawValue
    self.trackingArea = NSTrackingArea(rect: circleRect, options: NSTrackingAreaOptions(rawValue: flag), owner: self, userInfo: nil)
    self.addTrackingArea(self.trackingArea)
}

override func mouseEntered(theEvent: NSEvent) {
    self.hovered = true
    NSCursor.pointingHandCursor().set()
    self.needsDisplay = true
}

override func mouseExited(theEvent: NSEvent) {
    self.hovered = false
    NSCursor.arrowCursor().set()
    self.needsDisplay = true
}

override func updateLayer() {
    if(hovered){
        if (self.cell!.highlighted){
            self.layer?.backgroundColor = pressedBackgroundColor?.CGColor
        }
        else{
            self.layer?.backgroundColor = hoveredBackgroundColor?.CGColor
        }
    }
    else{
        self.layer?.backgroundColor = backgroundColor?.CGColor
    }
}

}

link: https://github.com/fancymax/HoverButton