Question

我已将此extension用于UISegmentedControl，因为您可以看到here.

但我希望UISegementedControl的工作略有不同。当我选择一个细分时，我希望所选细分的图像将颜色更改为colorGreyLight，而不是将背景颜色更改为colorGreyDark，并且选定的细分图像会更改为UIColor.clearColor() （你可以看到here）

那我怎么能这样做呢？

我的代码

UISegmented Control Extension：

extension UISegmentedControl {
    func removeBorders() {
        setBackgroundImage(imageWithColor(UIColor.clearColor()), forState: .Normal, barMetrics: .Default)
        setBackgroundImage(imageWithColor(tintColor), forState: .Selected, barMetrics: .Default)
        setDividerImage(imageWithColor(UIColor.clearColor()), forLeftSegmentState: .Normal, rightSegmentState: .Normal, barMetrics: .Default)
    }

    // create a 1x1 image with this color
    private func imageWithColor(color: UIColor) -> UIImage {
        let rect = CGRectMake(0.0, 0.0, 1.0, 1.0)
        UIGraphicsBeginImageContext(rect.size)
        let context = UIGraphicsGetCurrentContext()
        CGContextSetFillColorWithColor(context, color.CGColor);
        CGContextFillRect(context, rect);
        let image = UIGraphicsGetImageFromCurrentImageContext();
        UIGraphicsEndImageContext();
        return image
    }
}

UISegemented Control：

    let types = ["rectangle", "circle", "triangle"]
    shapeSelector = UISegmentedControl(items: types)
    shapeSelector.frame = CGRectMake(0, 0, sliderHeight*3 + 30, sliderHeight)
    shapeSelector.center = CGPoint(x: drawToolbar.bounds.width/2, y: sliderCenterY)
    shapeSelector.tintColor = colorGreyDark
    shapeSelector.removeBorders()
    shapeSelector.selectedSegmentIndex = 0 //default: select rectangle
    shapeSelector.addTarget(self, action: "selectShape:", forControlEvents: .ValueChanged)
    shapeSelector.setImage(UIImage(named: "rectangle"), forSegmentAtIndex: 0)
    shapeSelector.setImage(UIImage(named: "circle"), forSegmentAtIndex: 1)
    shapeSelector.setImage(UIImage(named: "triangle"), forSegmentAtIndex: 2)
    shapeSelector.contentMode = UIViewContentMode.ScaleAspectFit
    drawToolbar.addSubview(shapeSelector)

如果我有任何疑虑，请使用：

IOS 9.2
Swift 2
Xcode 7.2

更新好的，所以我按照Keyur的建议更改了我的代码（如下面的评论标记）

UISegmented Control Extension：

extension UISegmentedControl {
    func removeBorders() {
        setBackgroundImage(imageWithColor(UIColor.clearColor()), forState: .Normal, barMetrics: .Default)
        setBackgroundImage(imageWithColor(UIColor.clearColor()), forState: .Selected, barMetrics: .Default) //change to clear color
        setDividerImage(imageWithColor(UIColor.clearColor()), forLeftSegmentState: .Normal, rightSegmentState: .Normal, barMetrics: .Default)
    }

    // create a 1x1 image with this color
    private func imageWithColor(color: UIColor) -> UIImage {
        let rect = CGRectMake(0.0, 0.0, 1.0, 1.0)
        UIGraphicsBeginImageContext(rect.size)
        let context = UIGraphicsGetCurrentContext()
        CGContextSetFillColorWithColor(context, color.CGColor);
        CGContextFillRect(context, rect);
        let image = UIGraphicsGetImageFromCurrentImageContext();
        UIGraphicsEndImageContext();
        return image
    }
}

UISegemented Control：

    let types = ["rectangle", "circle", "triangle"]
    shapeSelector = UISegmentedControl(items: types)
    shapeSelector.frame = CGRectMake(0, 0, sliderHeight*3 + 30, sliderHeight)
    shapeSelector.center = CGPoint(x: drawToolbar.bounds.width/2, y: sliderCenterY)
    shapeSelector.tintColor = colorGreyDark
    shapeSelector.removeBorders()
    shapeSelector.selectedSegmentIndex = 0 //default: select rectangle
    (shapeSelector.subviews[0] as UIView).tintColor = colorGreyLight //added this line
    shapeSelector.addTarget(self, action: "selectShape:", forControlEvents: .ValueChanged)
    shapeSelector.setImage(UIImage(named: "rectangle"), forSegmentAtIndex: 0)
    shapeSelector.setImage(UIImage(named: "circle"), forSegmentAtIndex: 1)
    shapeSelector.setImage(UIImage(named: "triangle"), forSegmentAtIndex: 2)
    shapeSelector.contentMode = UIViewContentMode.ScaleAspectFit
    drawToolbar.addSubview(shapeSelector)

selectShape()功能：

func selectShape(sender: UISegmentedControl){
    switch sender.selectedSegmentIndex{
    case 0: //rectangle
        shapeType = "rectangle"
        (sender.subviews[0] as UIView).tintColor = colorGreyLight
        (sender.subviews[1] as UIView).tintColor = colorGreyDark
        (sender.subviews[2] as UIView).tintColor = colorGreyDark
    case 1: //circle
        shapeType = "circle"
        (sender.subviews[0] as UIView).tintColor = colorGreyDark
        (sender.subviews[1] as UIView).tintColor = colorGreyLight
        (sender.subviews[2] as UIView).tintColor = colorGreyDark
    case 2: //triangle
        shapeType = "triangle"
        (sender.subviews[0] as UIView).tintColor = colorGreyDark
        (sender.subviews[1] as UIView).tintColor = colorGreyDark
        (sender.subviews[2] as UIView).tintColor = colorGreyLight
    default:
        shapeType = "rectangle"
        (sender.subviews[0] as UIView).tintColor = colorGreyLight
        (sender.subviews[1] as UIView).tintColor = colorGreyDark
        (sender.subviews[2] as UIView).tintColor = colorGreyDark
    }
}

除非我尝试使用时，所选的形状并不总是突出显示的形状，因为您可以看到here。它似乎几乎随机地突出了形状，我不明白为什么。

对此的任何帮助将不胜感激！

Answer 1

在removeborders（）函数中设置颜色。

setBackgroundImage（imageWithColor（UIColor.clearColor（）），forState：.Normal，barMetrics：.Default） setBackgroundImage（imageWithColor（UIColor.lightGrayColor（）），forState：.Selected，barMetrics：.Default）

Answer 2

感谢this post.

，我找到了答案

显然选择的索引不是分配色调颜色的可靠方法。相反，我必须自己跟踪细分。

这就是我在创建UISegmentedControl shapeSelector之后所做的事情：

var segments: [UIView] = [UIView]()
for i in 0...shapeSelector.subviews.count-1{
    segments.append(shapeSelector.subviews[i])
}

在UISegmentedControl的功能中，我做了：

func selectShape(sender: UISegmentedControl){
    let i = sender.selectedSegmentIndex
    for s in segments{
        s.tintColor = colorGreyDark
    }
    segments[i].tintColor = colorGreyLight

    switch i{
    case 0:
        shapeType = "rectangle"
    case 1:
        shapeType = "circle"
    case 2:
        shapeType = "triangle"
    default:
        shapeType = "rectangle"
    }
}

现在一切都很完美！

完整代码

extension UISegmentedControl {
    func removeBorders() {
        setBackgroundImage(imageWithColor(UIColor.clearColor()), forState: .Normal, barMetrics: .Default)
        setBackgroundImage(imageWithColor(UIColor.clearColor()), forState: .Selected, barMetrics: .Default)
        setDividerImage(imageWithColor(UIColor.clearColor()), forLeftSegmentState: .Normal, rightSegmentState: .Normal, barMetrics: .Default)
}

    // create a 1x1 image with this color
    private func imageWithColor(color: UIColor) -> UIImage {
        let rect = CGRectMake(0.0, 0.0, 1.0, 1.0)
        UIGraphicsBeginImageContext(rect.size)
        let context = UIGraphicsGetCurrentContext()
        CGContextSetFillColorWithColor(context, color.CGColor);
        CGContextFillRect(context, rect);
        let image = UIGraphicsGetImageFromCurrentImageContext();
        UIGraphicsEndImageContext();
        return image
    }
}

class DrawViewController: UIViewController {

    var shapeSelector: UISegmentedControl = UISegmentedControl()
    var segments: [UIView] = [UIView]()

    override func viewDidLoad() {
        super.viewDidLoad()

        //set up shape selector
        let types = ["rectangle", "circle", "triangle"]
        shapeSelector = UISegmentedControl(items: types)
        shapeSelector.frame = CGRectMake(shapeTypeLabel.frame.maxX + sliderSpace, 0, sliderHeight*3 + 30, sliderHeight)
        shapeSelector.center.y = shapeTypeLabel.center.y
        shapeSelector.tintColor = colorGreyDark
        shapeSelector.removeBorders()
        shapeSelector.addTarget(self, action: "selectShape:", forControlEvents: .ValueChanged)
        shapeSelector.setImage(UIImage(named: "rectangle"), forSegmentAtIndex: 0)
        shapeSelector.setImage(UIImage(named: "circle"), forSegmentAtIndex: 1)
        shapeSelector.setImage(UIImage(named: "triangle"), forSegmentAtIndex: 2)
        for i in 0...shapeSelector.subviews.count-1{
            segments.append(shapeSelector.subviews[i])
        }
        shapeSelector.selectedSegmentIndex = 0 //default: select rectangle
        segments[0].tintColor = colorGreyLight
        shapeSelector.contentMode = UIViewContentMode.ScaleAspectFit
        drawToolbar.addSubview(shapeSelector)
    }

    func selectShape(sender: UISegmentedControl){
        let i = sender.selectedSegmentIndex
        for s in segments{
            s.tintColor = colorGreyDark
        }
        segments[i].tintColor = colorGreyLight

        switch i{
        case 0:
            shapeType = "rectangle"
        case 1:
            shapeType = "circle"
        case 2:
            shapeType = "triangle"
        default:
            shapeType = "rectangle"
        }
    }
}

自定义UISegmentedControl：如何更改所选片段图像的色调？

3 个答案: