Simple mouseover effect on NSButton

Question

I am creating a custom NSButtonCell for a custom rendering.

Now, I want to have different aspect depending if the mouse is over the button or not. How can

Answer 1

Swift 3:

Create the button with code or just use it's @IBOutlet. Then define the button's tracking area for mouse over (hover):

let area = NSTrackingArea.init(rect: yourButtonName.bounds,
                               options: [.mouseEnteredAndExited, .activeAlways], 
                               owner: self, 
                               userInfo: nil)
yourButtonName.addTrackingArea(area)

Then override mouseEntered and mouseExited, set whatever you want to change (button color, button image, button text,..) in these functions:

override func mouseEntered(with event: NSEvent) {
    print("Entered: \(event)")
}

override func mouseExited(with event: NSEvent) {
    print("Exited: \(event)")
}

If you have multiple buttons (with tracking area added for each) and you need to identify which button triggered the mouseEntered event, you can add some userInfo information for this purpose, so instead of:

userInfo: nil

Add your custom button name in userInfo for each button, for example:

userInfo: ["btnName": "yourButtonName"]

Then you can write a switch-case or if statements in your mouseEntered and mouseExited functions like this:

override func mouseEntered(with event: NSEvent) {
        // Identify which button triggered the mouseEntered event
        if let buttonName = event.trackingArea?.userInfo?.values.first as? String {
            switch (buttonName) {
            case "yourButtonName":
                //do whatever you want for this button..
            case "anotherButtonName":
                //do whatever you want for this button..
            default:
                print("The given button name: \"\(buttonName)\" is unknown!")
            }
        }
    }