Custom PageControl image - Swift

问题

I am trying to set an image for UIPageControl dots.

I need to change the default dots, instead of that I need an image. I used the below code

self.pageCtrl.currentPageIndicatorTintColor = UIColor.init(patternImage: UIImage(named: "Page Indicator_Selected")!)
self.pageCtrl.pageIndicatorTintColor = UIColor.init(patternImage: UIImage(named: "Page Indicator_Normal")!)

I could set the image in Pagecontrol but, it is overlapping with default dots.

回答1:

I improved Agent Smith's answer to work with any number of pages. You can 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
    }
}
}

回答2:

This approach works for me. I create a custom pageControl class and change the images for dots to be any custom image.

In the code below I changed the image for the first dot in pageControl with any custom image.

You can change updateDots() method as per your needs.

Hope it helps!!!

override func viewDidLoad() {
    super.viewDidLoad()

    let pageControl = CustomPageControl(frame: CGRect(x: 100, y: 100, width: 104, height: 40))
    pageControl.numberOfPages = 5
    pageControl.currentPage = 0
    self.view.addSubview(pageControl)
}


class CustomPageControl: UIPageControl {


var imageToBeReplacedByDot: UIImage {
    return // Image you want to replace with dots
}
var circleImage: UIImage {

    return //Default Image
}


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

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

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 {
        var imageView = self.imageView(forSubview: view)
        if imageView == nil {
            if i == 0 {
                imageView = UIImageView(image: imageToBeReplacedByDot)
            } else {
                imageView = UIImageView(image: circleImage)
            }
            imageView!.center = view.center
            view.addSubview(imageView!)
            view.clipsToBounds = false
        }
        if i == self.currentPage {
            imageView!.alpha = 1.0
        } else {
            imageView!.alpha = 0.5
        }
        i += 1
    }
}

fileprivate func imageView(forSubview 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
}
}

来源：https://stackoverflow.com/questions/47279137/custom-pagecontrol-image-swift