ios - 如何将分段 Controller 按钮从 UILabel 更改为 UIImage？

Question

我按照 youtube 上的本教程创建了一个自定义分段 Controller :https://www.youtube.com/watch?v=qT1ZEE2CBDQ

我已成功创建它并使其正常运行。但现在我想将 UILabel 更改为图像图标。

我尝试了几件事，例如，将“var labels : [String] = ["a", "b", "c"] "更改为 "var labels = UIImage(named: "..") 等”

这可能不正确，但值得一试!

这是我当前的代码，其中显示 UILabels:

@IBDesignable class ADVSegmentedControl: UIControl {

    private var labels = [UILabel]()



   // var items: [UIImage] = [UIImage(named: "heart")!,UIImage(named: "camera")!,UIImage(named: "cameraRoll")!]

    var items: [String] = ["Item 1", "Item 2", "Item 3"]
        {
        didSet {
            setupLabels()
        }
    }

    var selectedIndex : Int = 0 {
        didSet {
            displayNewSelectedIndex()
        }
    }

    @IBInspectable var selectedLabelColor : UIColor = UIColor.blackColor()
    @IBInspectable var unselectedLabelColor : UIColor = UIColor.grayColor()


    @IBInspectable var borderColor : UIColor = UIColor.blackColor() {
        didSet {
            layer.borderColor = borderColor.CGColor
        }
    }

    @IBInspectable var font : UIFont! = UIFont.systemFontOfSize(12) {
        didSet {
            setFont()
        }
    }

    override init(frame: CGRect) {
        super.init(frame: frame)

        setupView()
    }

    required init?(coder: NSCoder) {
        super.init(coder: coder)
        setupView()
    }

    func setupView(){


        //layer.borderColor = UIColor(white: 1.0, alpha: 0.5).CGColor
        layer.borderWidth = 1

        backgroundColor = UIColor.clearColor()

        setupLabels()

        addIndividualItemConstraints(labels, mainView: self, padding: 0)


    }







    func setupLabels(){

        for label in labels {
            label.removeFromSuperview()
        }

        labels.removeAll(keepCapacity: true)

        for index in 1...items.count {

            let label = UILabel(frame: CGRectMake(0, 0, 70, 40))
            label.text = items[index - 1]
            label.backgroundColor = UIColor.clearColor()
            label.textAlignment = .Center
            label.font = UIFont(name: "Avenir-Black", size: 15)
            label.textColor = index == 1 ? unselectedLabelColor : unselectedLabelColor
            label.translatesAutoresizingMaskIntoConstraints = false
            self.addSubview(label)
            labels.append(label)
        }

        addIndividualItemConstraints(labels, mainView: self, padding: 0)
    }









    override func beginTrackingWithTouch(touch: UITouch, withEvent event: UIEvent?) -> Bool {

        let location = touch.locationInView(self)

        var calculatedIndex : Int?
        for (index, item) in labels.enumerate() {
            if item.frame.contains(location) {
                calculatedIndex = index
            }
        }


        if calculatedIndex != nil {
            selectedIndex = calculatedIndex!
            sendActionsForControlEvents(.ValueChanged)
        }

        return false
    }

    func displayNewSelectedIndex(){
        for (index, item) in labels.enumerate() {
            item.textColor = unselectedLabelColor
        }

        let label = labels[selectedIndex]
        label.textColor = selectedLabelColor

        UIView.animateWithDuration(0.5, delay: 0.0, usingSpringWithDamping: 0.5, initialSpringVelocity: 0.8, options: [], animations: {


            }, completion: nil)
    }

    func addIndividualItemConstraints(items: [UIView], mainView: UIView, padding: CGFloat) {

        let constraints = mainView.constraints

        for (index, button) in items.enumerate() {

            let topConstraint = NSLayoutConstraint(item: button, attribute: NSLayoutAttribute.Top, relatedBy: NSLayoutRelation.Equal, toItem: mainView, attribute: NSLayoutAttribute.Top, multiplier: 1.0, constant: 0)

            let bottomConstraint = NSLayoutConstraint(item: button, attribute: NSLayoutAttribute.Bottom, relatedBy: NSLayoutRelation.Equal, toItem: mainView, attribute: NSLayoutAttribute.Bottom, multiplier: 1.0, constant: 0)

            var rightConstraint : NSLayoutConstraint!

            if index == items.count - 1 {

                rightConstraint = NSLayoutConstraint(item: button, attribute: NSLayoutAttribute.Right, relatedBy: NSLayoutRelation.Equal, toItem: mainView, attribute: NSLayoutAttribute.Right, multiplier: 1.0, constant: -padding)

            }else{

                let nextButton = items[index+1]
                rightConstraint = NSLayoutConstraint(item: button, attribute: NSLayoutAttribute.Right, relatedBy: NSLayoutRelation.Equal, toItem: nextButton, attribute: NSLayoutAttribute.Left, multiplier: 1.0, constant: -padding)
            }


            var leftConstraint : NSLayoutConstraint!

            if index == 0 {

                leftConstraint = NSLayoutConstraint(item: button, attribute: NSLayoutAttribute.Left, relatedBy: NSLayoutRelation.Equal, toItem: mainView, attribute: NSLayoutAttribute.Left, multiplier: 1.0, constant: padding)

            }else{

                let prevButton = items[index-1]
                leftConstraint = NSLayoutConstraint(item: button, attribute: NSLayoutAttribute.Left, relatedBy: NSLayoutRelation.Equal, toItem: prevButton, attribute: NSLayoutAttribute.Right, multiplier: 1.0, constant: padding)

                let firstItem = items[0]

                let widthConstraint = NSLayoutConstraint(item: button, attribute: .Width, relatedBy: NSLayoutRelation.Equal, toItem: firstItem, attribute: .Width, multiplier: 1.0  , constant: 0)

                mainView.addConstraint(widthConstraint)
            }

            mainView.addConstraints([topConstraint, bottomConstraint, rightConstraint, leftConstraint])
        }
    }

    func setSelectedColors(){
        for item in labels {
            item.textColor = unselectedLabelColor
        }

        if labels.count > 0 {
            labels[0].textColor = unselectedLabelColor
        }


    }

    func setFont(){
        for item in labels {
            item.font = font
        }
    }


}

如果有人可以提供帮助，我将非常感激!

致以诚挚的问候。

Answer 1

您可以有一个存储图像名称的字符串数组。例如

var images: [String] = ["image1.png", "image2.png", "image"]

在 setupLabels 中，您可以使用以下命令创建图像

var img = UIImage(named: images[index - 1])
let imageView = UIImageView(image: img!)
imageView.frame = CGRectMake(0, 0, 70, 40)
self.addSubview(imageView)