縮小UILabels的質量

Question

我使用Swift 3創建一個iOS界面，其中某些UIView包含（其中包括）UILabel s根據它們在屏幕上的位置放大和縮小。我的第一個方法是創建一個舒適的大尺寸（比如100x100）並填充視圖，然後根據需要使用CGAffineTransform(scaleX:y:)進行縮放，但是我注意到標籤中文本的縮小比例並不優雅，而且文本變得像素化並且在小尺度下接近不可讀。作爲比較（參見下面的示例），直接更改字體大小會得到更好的結果，但是我的視圖中的結構有些複雜，並且不得不根據某個大小因素重新繪製所有內容，這將是一件麻煩事。有沒有更好更平滑的方法來解決這個問題？

下面是我創建的一個示例項目，用於說明問題以及模擬器中的輸出（與iPhone本身相同），縮小視圖位於左側（紅色），更改的字體大小是右側（綠色）。

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

這可能一個答案 - 但不是真的適合評論，所以...

試試這個 - 它創造的黃色第三屆「欄」 - 背景視圖，使用.adjustsFontSizeToFitWidth。字體大小將根據包含標籤的視圖的大小自動調整。

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) 

    } 
}