Проблема с переключением представлений в UIStackView в зависимости от условия ⇐ IOS

[Anonymous]

В моем проекте iOS я работаю с UIStackView, который содержит несколько подпредставлений. Я хочу динамически переворачивать или перемещать вверх и вниз определенные представления в виде стека в зависимости от условия. В частности,
я пытаюсь манипулировать позициями двух текстовых полей с именами FIRST и SECOND. Однако я столкнулся с проблемой, из-за которой переворачивание работает правильно только при каждом втором касании или щелчке.
Вот мой код для того же

Код: Выделить всё

import UIKit
import Combine

import SnapKit

class ViewController: UIViewController {

private var toggleSubject = PassthroughSubject()
private var toggle = false
private var store = Set()

private lazy var topField: AppTextField = {
let view = AppTextField(title: "First")
view.translatesAutoresizingMaskIntoConstraints = false
return view
}()

private lazy var bottomField: AppTextField = {
let view = AppTextField(title: "Second")
view.translatesAutoresizingMaskIntoConstraints = false
return view
}()

private lazy var lineView: UIImageView = {
let view = UIImageView(frame: .zero)
view.backgroundColor = .red
view.translatesAutoresizingMaskIntoConstraints = false
return view
}()

private lazy var stackView: UIStackView = {
let view = UIStackView(arrangedSubviews: [topField, lineView, bottomField, toggleButton])
view.axis  = .vertical
view.spacing = 4.0
view.distribution = .fill
view.alignment = .fill
view.translatesAutoresizingMaskIntoConstraints = false
return view
}()

private lazy var toggleButton: UIButton = {
let view = UIButton(frame: .zero)
view.setTitle("Toggle", for: .normal)
view.setTitleColor(.white, for: .normal)
view.setTitleColor(.systemYellow, for: .highlighted)
view.backgroundColor = .darkGray
view.translatesAutoresizingMaskIntoConstraints = false
return view
}()

private lazy var selectedTopFieldLabel: UILabel = {
let view = UILabel(frame: .zero)
view.textAlignment = .center
view.translatesAutoresizingMaskIntoConstraints = false
return view
}()

override func viewDidLoad() {
super.viewDidLoad()
self.view.addSubview(stackView)
self.view.addSubview(selectedTopFieldLabel)
toggleSubject.send(toggle)

stackView.snp.makeConstraints { make in
make.leading.trailing.centerY.equalToSuperview().inset(16)
}

lineView.snp.makeConstraints { make in
make.height.equalTo(0.5)
}

selectedTopFieldLabel.snp.makeConstraints { make in
make.top.equalToSuperview().offset(200)
}

toggleButton.addTarget(self, action: #selector(toggleButtonAction), for: .touchUpInside)

toggleSubject.sink { toggle in
print("---> Changed Toggle",toggle)
self.updateUI(toggle: toggle)
UIView.animate(withDuration: 0.25) {
self.stackView.layoutIfNeeded()
}
}.store(in: &store)
self.updateUI(toggle: toggle)
}

@objc func toggleButtonAction() {
toggle.toggle()
toggleSubject.send(toggle)
}

private func updateUI(toggle: Bool) {
let arrangedSubviews = self.stackView.arrangedSubviews

guard var first = arrangedSubviews[0] as? AppTextField,
var second = arrangedSubviews[2] as? AppTextField else {return}
stackView.arrangedSubviews.forEach({$0.removeFromSuperview()})
let changedViews = toggle ? [first, lineView, second, toggleButton] : [second, lineView, first , toggleButton]

guard let firstTextField = changedViews.first as? AppTextField,
let firstfieldPlaceholder = firstTextField.placeholder else {return}

self.selectedTopFieldLabel.text =  "Selected On Top " + " -> "  + firstfieldPlaceholder

changedViews.forEach { view in
self.stackView.addArrangedSubview(view)
}
// Update constraints
UIView.animate(withDuration: 0.25) {
self.stackView.setNeedsLayout()
self.stackView.layoutIfNeeded()
}
}
}

class AppTextField: UIView {

private lazy var inputField: UITextField = {
let textField = UITextField(frame: .zero)
textField.backgroundColor = .lightGray.withAlphaComponent(0.15)
textField.translatesAutoresizingMaskIntoConstraints = false
return textField
}()

var title: String? {
get { return inputField.placeholder }
set { inputField.placeholder = newValue }
}

var placeholder: String? {
get { return inputField.placeholder }
set { inputField.placeholder = newValue }
}

var text: String? {
get { return inputField.text }
set { inputField.text = newValue }
}

init(title: String) {
super.init(frame: .zero)
self.title = title
setupViews()
}

@available(*, unavailable)
required init?(coder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}

private func setupViews() {
addSubview(inputField)
inputField.snp.makeConstraints { make in
make.edges.equalToSuperview()
make.height.equalTo(48)
}
}
}

Заранее спасибо.

Подробнее здесь: https://stackoverflow.com/questions/783 ... -condition