ios - 自定义 UISegmentedControl : how change tint color of selected segment's image?

Question

我用过这个extension对于 UISegmentedControl 其工作方式如您所见 here.

但我希望 UISegementedControl 的工作方式略有不同。当我选择一个片段时，我希望所选片段的图像将颜色更改为 colorGreyLight 而不是将背景颜色更改为 colorGreyDark 并将所选片段图像更改为 UIColor.clearColor()(如你所见 here )

那我该怎么做呢？

我的代码

UISegmented 控件扩展:

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
    }
}

UI分段控制:

    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)

如果对我使用的有任何疑问:

• iOS 9.2
• swift 2
• Xcode 7.2

---

更新 好的，我已经按照 Keyur 的建议更改了我的代码(如下面的评论标记)

UISegmented 控件扩展:

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
    }
}

UI分段控制:

    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() 函数:

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
    }
}

除非我尝试过，否则所选形状并不总是突出显示的形状，如您所见here .它似乎几乎是随机地突出显示形状，我不明白为什么。

如有任何帮助，我们将不胜感激!

Answer 1

(shapeSelector.subviews[2] as UIView).tintColor = UIColor .redColor()
(shapeSelector.subviews[1] as UIView).tintColor = UIColor .redColor()
(shapeSelector.subviews[0] as UIView).tintColor = UIColor .redColor()