用UIViews编程填充的UIStackView不在UIScrollView内滚动

Question

I'm still a SO and Swift newbie, so please, be patient :-)

I have a UIViewController .

Inside this viewcontroller there's a UIScrollView .

Inside the UIScrollView there's a UIStackView (pinned with AutoLayout at 0,0,0,0 and centered vertically and horizontally), with horizontal axis.

My goal is to add subviews to the stackview and make the scrollview scroll horizontally.

So, I did the following:

import UIKit

    class ViewController: UIViewController, UIScrollViewDelegate {

        @IBOutlet weak var scroller: UIScrollView!
        @IBOutlet weak var stack: UIStackView!

        override func viewDidLoad() {

            super.viewDidLoad()
            scroller.delegate = self

            for i in 0..<10 {

                let customView = UIView(frame: CGRect(x: 0, y: 0, width: 240, height: 128))
                // .random is unimportant here
                customView.backgroundColor = .random()
                stack.addArrangedSubview(customView)

            }

        }

        override func viewDidLayoutSubviews(){
            self.scroller.contentSize = CGSize(width:2400,height:128)
            print(self.scroller.contentSize) // 2400
            print(self.stack.subviews)
        }

        func scrollViewDidScroll(_ scrollView: UIScrollView) {
            print("scrollin'")
        }


    }

Problem is there is something I must be missing because the scrollview doesn't scroll at all. I only see one view (of course, anytime with a different color).

I'm sure the views are loaded because this is second print output:

[<UIView: 0x159e01a10; frame = (0 0; 240 128); layer = <CALayer: 0x28115d7a0>>, <UIView: 0x159e03f10; frame = (0 0; 240 128); layer = <CALayer: 0x28115d800>>, <UIView: 0x159e046d0; frame = (0 0; 240 128); layer = <CALayer: 0x28115d960>>, <UIView: 0x159e0e410; frame = (0 0; 240 128); layer = <CALayer: 0x28115da80>>, <UIView: 0x159e0e7c0; frame = (0 0; 240 128); layer = <CALayer: 0x28115db20>>, <UIView: 0x159e0e9a0; frame = (0 0; 240 128); layer = <CALayer: 0x28115da60>>, <UIView: 0x159e0eb80; frame = (0 0; 240 128); layer = <CALayer: 0x28115dbe0>>, <UIView: 0x159e0ed60; frame = (0 0; 240 128); layer = <CALayer: 0x28115dc80>>, <UIView: 0x159e0ef40; frame = (0 0; 240 128); layer = <CALayer: 0x28115dd20>>, <UIView: 0x159e0f120; frame = (0 0; 240 128); layer = <CALayer: 0x28115ddc0>>]

So, what is it happening? Why the scrollview doesn't scroll?

Answer 1

Replace this

  let customView = UIView(frame: CGRect(x: 0, y: 0, width: 240, height: 128))

with

let customView = UIView(frame: CGRect(x: CGFloat( i * 240 ) , y: 0, width: 240, height: 128))

I see no need for the stackView , and

scroller.addSubview(customView)

Look to this Scroller

Answer 2

try this code, i hope it helps you.

override func viewDidLoad() {

    super.viewDidLoad()
    scroller.delegate = self

        for i in 0..<10 {
            let xPosition = 240 * CGFloat(i)
            let customView = UIView(frame: CGRect(x: xPosition, y: 0, width: 240, height: 128))
            // .random is unimportant here
            customView.backgroundColor = .random()
            scroller.addSubview(customView)
        }
    scroller.contentSize.width = 2400
}