nil in UIPageControl view subview - ios

Question

I'm new in ios swift and want to change UIPageControl dots size via images.
I found same issue here (UIPageControl custom class - found nil changing image to the dots)
but seems the answer is wrong, still in page control view subviews(UIImageView) is nil
As I don't have enough reputation have to ask here.
here how I'm adding image views to the scroll view
let imgOne = UIImageView(frame: CGRectMake(0, 0,scrollViewWidth, scrollViewHeight))
imgOne.image = UIImage(named: "1")
let imgTwo = UIImageView(frame: CGRectMake(scrollViewWidth, 0,scrollViewWidth, scrollViewHeight))
imgTwo.image = UIImage(named: "2")
let imgThree = UIImageView(frame: CGRectMake(scrollViewWidth*2, 0,scrollViewWidth, scrollViewHeight))
imgThree.image = UIImage(named: "3")
let imgFour = UIImageView(frame: CGRectMake(scrollViewWidth*3, 0,scrollViewWidth, scrollViewHeight))
imgFour.image = UIImage(named: "4")
self.scrollView.addSubview(imgOne)
self.scrollView.addSubview(imgTwo)
self.scrollView.addSubview(imgThree)
self.scrollView.addSubview(imgFour)
and below the answer to the problem
class PageControl: UIPageControl {
var activeImage: UIImage!
var inactiveImage: UIImage!
override var currentPage: Int {
willSet {
self.updateDots()
}
}
convenience init(activeImage: UIImage, inactiveImage: UIImage) {
self.init()
self.activeImage = activeImage
self.inactiveImage = inactiveImage
self.pageIndicatorTintColor = UIColor.clearColor()
self.currentPageIndicatorTintColor = UIColor.clearColor()
}
func updateDots() {
for var i = 0; i < count(subviews); i++ {
var view: UIView = subviews[i] as! UIView
if count(view.subviews) == 0 {
self.addImageViewOnDotView(view, imageSize: activeImage.size)
}
var imageView: UIImageView = view.subviews.first as! UIImageView // nil
imageView.image = self.currentPage == i ? activeImage : inactiveImage
}
}
// MARK: - Private
func addImageViewOnDotView(view: UIView, imageSize: CGSize) {
var frame = view.frame
frame.origin = CGPointZero
frame.size = imageSize
var imageView = UIImageView(frame: frame)
imageView.contentMode = UIViewContentMode.Center
view.addSubview(imageView)
}
}

Answer 1

Spending few days I solved it in the following way...
Don't know how is good the solution, feel free to to improve...
There was 2 problems
1: in function updateDots, should look like this
func updateDots() {
for var i = 0; i < subviews.count; i++ {
var imageView: UIImageView? = nil
let view: UIView = subviews[i]
if (view.subviews.first is UIImageView) {
if (subviews.count == 0) {
addImageViewOnDotView(view, imageSize: activeImage.size)
}
imageView = (view.subviews.first as! UIImageView)
imageView!.image = self.currentPage == i ? activeImage : inactiveImage
}
if (imageView == nil) {
imageView = UIImageView(frame: CGRectMake(0.0, 0.0, view.frame.size.width, view.frame.size.height));
imageView!.image = self.currentPage == i ? activeImage : inactiveImage
view.addSubview(imageView!)
}
}
}
2: When call this function, should be after (didSet) scroll not before (willSet)
override var currentPage: Int {
didSet {
self.updateDots()
}
}