Custom UIPageControl with dot images

Question

When I needed to custom my UIPageControl I used this and this solution.

Slightly modifying it for the new version of swift we have :

class myPageCont         


        

Answer 1

I improved @CodenameDuchess's answer a bit. You can also customize the images on xibs/storyboards.

class CustomPageControl: UIPageControl {

@IBInspectable var currentPageImage: UIImage?

@IBInspectable var otherPagesImage: UIImage?

override var numberOfPages: Int {
    didSet {
        updateDots()
    }
}

override var currentPage: Int {
    didSet {
        updateDots()
    }
}

override func awakeFromNib() {
    super.awakeFromNib()
    pageIndicatorTintColor = .clear
    currentPageIndicatorTintColor = .clear
    clipsToBounds = false
}

private func updateDots() {

    for (index, subview) in subviews.enumerated() {
        let imageView: UIImageView
        if let existingImageview = getImageView(forSubview: subview) {
            imageView = existingImageview
        } else {
            imageView = UIImageView(image: otherPagesImage)

            imageView.center = subview.center
            subview.addSubview(imageView)
            subview.clipsToBounds = false
        }
        imageView.image = currentPage == index ? currentPageImage : otherPagesImage
    }
}

private func getImageView(forSubview view: UIView) -> UIImageView? {
    if let imageView = view as? UIImageView {
        return imageView
    } else {
        let view = view.subviews.first { (view) -> Bool in
            return view is UIImageView
        } as? UIImageView

        return view
    }
}
}

Answer 2

Swift 3.0 ... you know if you are OK with accepting stated risk: "Modifying the subviews of an existing control is fragile".

You will have to call "updateDots()" in viewDidAppear() and your valueChanged handler for the page control.

 import UIKit

 class CustomImagePageControl: UIPageControl {

   let activeImage:UIImage = UIImage(named: "SelectedPage")!
   let inactiveImage:UIImage = UIImage(named: "UnselectedPage")!

   override func awakeFromNib() {
         super.awakeFromNib()

         self.pageIndicatorTintColor = UIColor.clear
         self.currentPageIndicatorTintColor = UIColor.clear
         self.clipsToBounds = false
    }

    func updateDots() {
         var i = 0
         for view in self.subviews {
             if let imageView = self.imageForSubview(view) {
                 if i == self.currentPage {
                     imageView.image = self.activeImage
                 } else {
                     imageView.image = self.inactiveImage
                 }
                 i = i + 1
             } else {
                 var dotImage = self.inactiveImage
                 if i == self.currentPage {
                     dotImage = self.activeImage
                 }
                 view.clipsToBounds = false
                 view.addSubview(UIImageView(image:dotImage))
                 i = i + 1
             }
         }
     }

     fileprivate func imageForSubview(_ view:UIView) -> UIImageView? {
         var dot:UIImageView?

         if let dotImageView = view as? UIImageView {
             dot = dotImageView
         } else {
             for foundView in view.subviews {
                 if let imageView = foundView as? UIImageView {
                     dot = imageView
                     break
                 }
             }
         }

         return dot
     }
 }

Answer 3

You can use UIStackView to achieve the effect you want.

Put your activeImageView and other inactiveImageViews into aStackView. Than just change the index of activeImageView in scrollViewDidScroll(_:).

func scrollViewDidScroll(_ scrollView: UIScrollView) {
  let index = Int(scrollView.contentOffset.x / scrollView.frame.width)
  aStackView.insertArrangedSubview(activeImageView, at: index)
}  

ps. UIStackView's insertArrangedSubview(_:at:) just updates the stack index of the arranged subview if it's already in the arrangedSubviews list.

Answer 4

Apple had introduced some new APIs for UIPageControll. From iOS 14 there is an option for providing a custom image.

Here is the updated code supporting iOS 14

class CustomPageControl: UIPageControl {

@IBInspectable var currentPageImage: UIImage?

@IBInspectable var otherPagesImage: UIImage?

override var numberOfPages: Int {
    didSet {
        updateDots()
    }
}

override var currentPage: Int {
    didSet {
        updateDots()
    }
}

override func awakeFromNib() {
    super.awakeFromNib()
    if #available(iOS 14.0, *) {
        defaultConfigurationForiOS14AndAbove()
    } else {
        pageIndicatorTintColor = .clear
        currentPageIndicatorTintColor = .clear
        clipsToBounds = false
    }
}

private func defaultConfigurationForiOS14AndAbove() {
    if #available(iOS 14.0, *) {
        for index in 0..<numberOfPages {
            let image = index == currentPage ? currentPageImage : otherPagesImage
            setIndicatorImage(image, forPage: index)
        }

        // give the same color as "otherPagesImage" color.
        pageIndicatorTintColor = .gray
        
        // give the same color as "currentPageImage" color.
        currentPageIndicatorTintColor = .red 
        /*
         Note: If Tint color set to default, Indicator image is not showing. So, give the same tint color based on your Custome Image.
        */
    }
}

private func updateDots() {
    if #available(iOS 14.0, *) {
        defaultConfigurationForiOS14AndAbove()
    } else {
        for (index, subview) in subviews.enumerated() {
            let imageView: UIImageView
            if let existingImageview = getImageView(forSubview: subview) {
                imageView = existingImageview
            } else {
                imageView = UIImageView(image: otherPagesImage)
                
                imageView.center = subview.center
                subview.addSubview(imageView)
                subview.clipsToBounds = false
            }
            imageView.image = currentPage == index ? currentPageImage : otherPagesImage
        }
    }
}

private func getImageView(forSubview view: UIView) -> UIImageView? {
    if let imageView = view as? UIImageView {
        return imageView
    } else {
        let view = view.subviews.first { (view) -> Bool in
            return view is UIImageView
        } as? UIImageView

        return view
    }
}
}