Change lazy button opacity from outside of the class - ios

Question

I need to change alpha value of the button in another class. But the problem is button created as "lazy var" so I can not change that value.
lazy var middleButton: UIButton = {
let button = UIButton(type: .custom)
button.frame.size = CGSize(width: 56, height: 56)
button.layer.cornerRadius = button.frame.width / 2
button.layer.masksToBounds = true
button.backgroundColor = .white
button.setImage(UIImage(named: "iconBasket"), for: .normal)
button.contentMode = .center
button.imageView?.contentMode = .scaleAspectFit
button.imageEdgeInsets = UIEdgeInsets(top: 0, left: 0, bottom: 0, right: 0)
button.addTarget(self, action: #selector(btnBasketClicked))
addSubview(button)
return button
}()
I want this button's alpha as 0.2 when view is scrolling. Here is the code
extension ProductListView: UIScrollViewDelegate{
func scrollViewDidScroll(_ scrollView: UIScrollView) {
if scrollView.panGestureRecognizer.translation(in: scrollView).y < 0{
// alpha = 0.2
MyTabBar.shared.scrollDown()
}
else{
// alpha = 1.0
MyTabBar.shared.scrollUp()
}
}
}
func scrollDown(){
middleButton.alpha = 0.2
}
I've tried lots of way but doesn't work. Calling "addSubView()" function in "layoutSubviews()" solve my problem but this causes another problem which my function "basketButtonClicked()" are not called. I used Delegate pattern and here it is.
protocol BasketButtonDelegate: class {
func basketButtonClicked()
}
#objc private func btnBasketClicked(_ sender: UIButton!){
delegate?.basketButtonClicked()
}
override func layoutSubviews() {
super.layoutSubviews()
addSubview(middleButton)
}
When I call "addSubView" function in "layoutSubviews()", "basketbuttonClicked" never called.
extension TabCoordinator : BasketButtonDelegate
{
func basketButtonClicked(){
log.debug("basketButtonClicked")
let coor = CartCoordinator(navigationController, hidesBar: true)
childCoordinators.append(coor)
coor.start()
}
}
(I assigned delegate so the problem is not about it.)
A bit complicated but I hope we can figure it out.

Answer 1

You need to add protocol to your MyTabBar class . It should be like this
class MyTabBar {
static var shared = MyTabBar()
weak var delegate : abc?
func scrollDown(){
delegate?.xyz()
}
}
protocol abc : AnyObject {
func xyz()
}
And in your class
class btnView : UIView , abc{
lazy var middleButton: UIButton = {
let button = UIButton(type: .custom)
button.frame.size = CGSize(width: 56, height: 56)
button.layer.cornerRadius = button.frame.width / 2
button.layer.masksToBounds = true
button.backgroundColor = .red
button.contentMode = .center
button.imageView?.contentMode = .scaleAspectFit
button.imageEdgeInsets = UIEdgeInsets(top: 0, left: 0, bottom: 0, right: 0)
button.addTarget(self, action: #selector(btnBasketClicked), for: .touchUpInside)
return button
}()
required init?(coder: NSCoder) {
super.init(coder: coder)
}
override init(frame: CGRect) {
super.init(frame: frame)
}
#objc func btnBasketClicked(){
print("Im here")
}
func addMiddleButton(){
self.addSubview(middleButton)
}
func alphaaa(){
self.middleButton.alpha = 0.2
}
func xyz() {
self.alphaaa()
}
}
Last , in your ProductListView create and instance of your view , or if you add with autolayout just call 2. function in your viewDidLoad
var viewwww = btnView(frame: CGRect(x: 10, y: 10, width: 100, height: 100))
viewwww.addMiddleButton() // call to add btn to custom view
and extension
func scrollViewDidScroll(_ scrollView: UIScrollView) {
if scrollView.panGestureRecognizer.translation(in: scrollView).y < 0{
// alpha = 0.2
MyTabBar.shared.delegate = viewwww
MyTabBar.shared.scrollDown()
}
else{
// alpha = 1.0
MyTabBar.shared.scrollUp()
}
}