How to use a UIButton as a toggle switch

Question

I am using a UIButton of custom type and what I want is use it like a toggle switch with the change of image. Like when it is clicked if previously it was not in selected mo

Answer 1

In order to do so we can use UIButton Subclass:

class UIToggleButton: UIButton {
    fileprivate let onImage: UIImage
    fileprivate let offImage: UIImage
    fileprivate let target: AnyObject
    fileprivate let onAction: Selector
    fileprivate let offAction: Selector
    var isOn: Bool {
        didSet {
            let image = isOn ? onImage : offImage
            setImage(image, for: UIControlState())
        }
    }

    init(onImage: UIImage,
        offImage: UIImage,
        target: AnyObject,
        onAction: Selector,
        offAction: Selector)
    {
        isOn = false
        self.onImage = onImage
        self.offImage = offImage
        self.target = target
        self.onAction = onAction
        self.offAction = offAction
        super.init(frame: CGRect.zero)
        setImage(offImage, for: UIControlState())
        addTarget(self, action: #selector(UIToggleButton.tapAction), for: .touchUpInside)
    }

    required init?(coder aDecoder: NSCoder) {
        fatalError("init(coder:) has not been implemented")
    }

    @objc func tapAction() {
        let sel = isOn ? onAction : offAction
        isOn = !isOn
        _ = target.perform(sel)
    }
}