滚动查看不滚动到底部

我正在努力与ScrollView的工作方式。我观看了scrollview上的视频教程，你必须添加一个滚动视图，然后UIView，然后添加约束，并设置视图控制器为自由形式，并将高度设置为1000.滚动查看不滚动到底部

在我的应用程序中，我正在加载3优惠券是图像视图，这些图像视图是以编程方式设置的。这里的代码，任何人都可以请帮我使用scrollViews？谢谢。

import UIKit 

class ViewController: UIViewController { 

@IBOutlet weak var scrollView: UIScrollView! 

@IBOutlet weak var UIView: UIView! 

struct MyCoupons { 
    static var couponsString: UIImage? 
    static var siteCoupons: [String?] = [] 
    static var count: Int = 0 
} 

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

} 


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

override func viewDidAppear(_ animated: Bool) { 
    var i: Int = 0 
    var x: Int = 0 
    var y: Int = 0 
    var width: Int = 0 
    var height: Int = 0 

    ViewController.PopulateDataCoupons() 

    i=0 
    height = 300 
    repeat { 
     let imageName = MyCoupons.siteCoupons[i]//"Coupons1.jpg" 
     let image = UIImage(named: imageName!) 
     let imageView = UIImageView(image: image!) 

     y = i * height + 50 
     imageView.frame = CGRect(x: 50, y: y, width: 250, height: 300) 

     view.addSubview(imageView) 
     i += 1 

    } 
     while (i < MyCoupons.count-1) 
} 

public class func PopulateDataCoupons() { 
    var i = 0 
    var abc: String 


    if let path = Bundle.main.path(forResource: "Coupons", ofType: "txt") { 
     do { 
      let data = try String(contentsOfFile: path, encoding: .utf8) 
      let myStrings = data.components(separatedBy: .newlines) 
      abc = myStrings.joined(separator: ",") 

      let couponsArr = abc.components(separatedBy: ",") 
      print("couponsArr.count", couponsArr.count) 

      repeat { 
       MyCoupons.siteCoupons.append(couponsArr[i]) 
       i+=1 
      } while i < ((couponsArr.count)-1) 

      MyCoupons.count = couponsArr.count 
     } catch { 
      print(error) 
     } 
    } 

}

}