缩小的 UILabel 的质量

Question

我正在使用 Swift 3 创建一个 iOS 界面，其中一些包含（除其他外）UILabels 的 UIViews 会根据它们在屏幕上的位置进行放大和缩小。我的第一种方法是以舒适的大尺寸（比如 100x100）创建和填充视图，然后根据需要使用 CGAffineTransform(scaleX:y:) 缩放它们，但是我注意到标签中文本的缩小一点也不优雅，并且文本在小范围内变得像素化并且接近不可读。作为比较（参见下面的示例），直接更改字体大小会产生更好的结果，但是我的视图中的结构有些复杂，并且必须根据某些大小因素重新绘制所有内容会很麻烦。有没有更好更顺畅的方法来解决这个问题？

这是我为说明问题而创建的示例项目，以及模拟器中的输出（与 iPhone 本身相同），缩小的视图位于左侧（红色），更改后的字体大小位于右侧（绿色）。

class ViewController: UIViewController {

    override func viewDidLoad() {
        super.viewDidLoad()
        // Do any additional setup after loading the view, typically from a nib.

        for i in 1...10 {
            let f = CGFloat(1.0) / CGFloat(i)
            let view1 = UIView(frame: CGRect(x: 0, y: 0, width: 150, height: 50))
            view1.backgroundColor = UIColor.red
            let label1 = UILabel(frame: CGRect(x: 0, y: 0, width: 150, height: 50))
            label1.text = "\(100 / i)%"
            label1.font = UIFont(name: "Verdana", size: 24.0)
            label1.textAlignment = .right
            view1.addSubview(label1)
            view1.transform = CGAffineTransform(scaleX: f, y: f)
            view1.center = CGPoint(x: 160 - 75.0 * f, y: CGFloat(60 * i) + 25.0 * f)
            self.view.addSubview(view1)

            let view2 = UIView(frame: CGRect(x: CGFloat(170), y: CGFloat(60 * i), width: 150 * f, height: 50 * f))
            view2.backgroundColor = UIColor.green
            let label2 = UILabel(frame: CGRect(x: 0, y: 0, width: 150 * f, height: 50 * f))
            label2.text = "\(100 / i)%"
            label2.font = UIFont(name: "Verdana", size: 24.0 * f)
            view2.addSubview(label2)
            self.view.addSubview(view2)

        }

    }

    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
    }


}

Answer 1

这可能是一个答案 - 但不太适合发表评论，所以...

试一试 - 它使用.adjustsFontSizeToFitWidth 创建黄色背景视图的第三“列”。字体大小将根据包含标签的视图大小自动调整。

override func viewDidLoad() {
    super.viewDidLoad()
    // Do any additional setup after loading the view, typically from a nib.

    for i in 1...10 {
        let f = CGFloat(1.0) / CGFloat(i)
        let view1 = UIView(frame: CGRect(x: 0, y: 0, width: 150, height: 50))
        view1.backgroundColor = UIColor.red
        let label1 = UILabel(frame: CGRect(x: 0, y: 0, width: 150, height: 50))
        label1.text = "\(100 / i)%"
        label1.font = UIFont(name: "Verdana", size: 24.0)
        label1.textAlignment = .right
        view1.addSubview(label1)
        view1.transform = CGAffineTransform(scaleX: f, y: f)
        view1.center = CGPoint(x: 160 - 75.0 * f, y: CGFloat(60 * i) + 25.0 * f)
        self.view.addSubview(view1)

        let view2 = UIView(frame: CGRect(x: CGFloat(170), y: CGFloat(60 * i), width: 150 * f, height: 50 * f))
        view2.backgroundColor = UIColor.green
        let label2 = UILabel(frame: CGRect(x: 0, y: 0, width: 150 * f, height: 50 * f))
        label2.text = "\(100 / i)%"
        label2.font = UIFont(name: "Verdana", size: 24.0 * f)
        view2.addSubview(label2)
        self.view.addSubview(view2)

        let view3 = UIView(frame: CGRect(x: CGFloat(270), y: CGFloat(60 * i), width: 150 * f, height: 50 * f))
        view3.backgroundColor = UIColor.yellow
        let label3 = UILabel(frame: view3.bounds)
        label3.text = "\(100 / i)%"
        label3.font = UIFont(name: "Verdana", size: 24.0)
        label3.adjustsFontSizeToFitWidth = true
        label3.minimumScaleFactor = 0.05
        label3.numberOfLines = 0
        // we want the label to resize with the view, if the view frame changes
        label3.autoresizingMask = [.flexibleWidth, .flexibleHeight]
        view3.autoresizesSubviews = true
        view3.addSubview(label3)
        self.view.addSubview(view3)

    }
}