Insert Space To Scroll View on Drag end

ViewControler.swift

//
//  ViewController.swift
//  ScrollViewInsertTest
//
//  Created by Terry Sahaidak on 18.10.2023.
//

import UIKit

class ViewController: UIViewController, UIScrollViewDelegate {
  
  let scrollView = UIScrollView()
  let stackView = UIStackView()
  
  override func viewDidLoad() {
    super.viewDidLoad()
    setupScrollViewWithStackView()
    scrollView.delegate = self
  }
  
  func scrollViewDidEndDragging(_ scrollView: UIScrollView, willDecelerate decelerate: Bool) {
    if (scrollView.contentOffset.y < -100) {
      scrollView.bounces = false
      let myEmptyView = UIView()
      myEmptyView.heightAnchor.constraint(equalToConstant: scrollView.contentOffset.y * -1 - 60).isActive = true
      myEmptyView.backgroundColor = .white
      stackView.insertArrangedSubview(myEmptyView, at: 0)
    }
  }
  
  func scrollViewDidEndDecelerating(_ scrollView: UIScrollView) {
     scrollView.bounces = true
  }
  
  
  func setupScrollViewWithStackView() {
    scrollView.frame = view.bounds
    scrollView.autoresizingMask = [.flexibleWidth, .flexibleHeight]
    view.addSubview(scrollView)
    
    stackView.axis = .vertical
    stackView.distribution = .fill
    stackView.alignment = .fill
    stackView.spacing = 10 // adjust this value for spacing between text views
    
    scrollView.addSubview(stackView)
    
    stackView.translatesAutoresizingMaskIntoConstraints = false
    NSLayoutConstraint.activate([
      stackView.topAnchor.constraint(equalTo: scrollView.topAnchor),
      stackView.bottomAnchor.constraint(equalTo: scrollView.bottomAnchor),
      stackView.leadingAnchor.constraint(equalTo: scrollView.leadingAnchor),
      stackView.trailingAnchor.constraint(equalTo: scrollView.trailingAnchor),
      stackView.widthAnchor.constraint(equalTo: scrollView.widthAnchor)
    ])
    
    setupTextViews(in: stackView)
  }
  
  func setupTextViews(in stackView: UIStackView) {
    for i in 1...20 {
      let textView = UITextView()
      textView.text = "Item \(i)"
      textView.heightAnchor.constraint(equalToConstant: 40).isActive = true
      stackView.addArrangedSubview(textView)
    }
  }
}