带有嵌套堆栈视图的 Swift UIStackView 间距答案

【问题标题】：Swift UIStackView spacing with nested stack view(s)带有嵌套堆栈视图的 Swift UIStackView 间距
【发布时间】：2021-04-27 06:50:01
【问题描述】：

按照 Apple 的指南 here（我已改为以编程方式完成），我创建了 3 个嵌套在垂直堆栈视图中的水平堆栈视图。为了使文本字段对齐，它们也都位于水平堆栈视图中。

有没有办法快速浏览文本字段堆栈视图，以便我可以看到 3 个字符的占位符文本？我也尝试过.fill、.fillProportionally 和其他人，但水平堆栈视图的标签最终为 50/50

我是自动布局的新手，所以我将其构建为一个学习练习。必须有更好的方法来做到这一点，对吧？

类似这样（1/4-1/3 的标签空间和 2/3-3/4 的文本字段）。

import UIKit

class RunningPaceCalculatorViewController: UIViewController {

private lazy var timeDistancePaceStackView: UIStackView = {
    let timeStackView = UIStackView.textFieldsStackView("Time")
    let distanceStackView = UIStackView.distanceStackView()
    let paceStackView = UIStackView.textFieldsStackView("Pace")
    return UIStackView.customStackView(.vertical, backgroundColor: .systemTeal, subviews: [timeStackView, distanceStackView, paceStackView])
}()

private lazy var buttonStackView: UIStackView = {
    return UIStackView.buttonStackView()
}()

private lazy var constainerStackView: UIStackView = {
    return UIStackView.customStackView(.vertical, backgroundColor: .gray, subviews: [timeDistancePaceStackView, buttonStackView])
}()

override func viewDidLoad() {
    setUpView()
}

func setUpView() {
    view.backgroundColor = .orange
    view.addSubview(constainerStackView)
    
    NSLayoutConstraint.activate([
        constainerStackView.heightAnchor.constraint(equalTo: view.heightAnchor, multiplier: 0.55),
        constainerStackView.centerXAnchor.constraint(equalTo: view.centerXAnchor),
        constainerStackView.centerYAnchor.constraint(equalTo: view.centerYAnchor),
        constainerStackView.leadingAnchor.constraint(equalTo: view.leadingAnchor, constant: 10),
        constainerStackView.trailingAnchor.constraint(equalTo: view.trailingAnchor, constant: -10)
    ])
}
}

private extension UITextField {
static func customTextField(_ placeholder: String) -> UITextField {
    let textField = UITextField()
    textField.placeholder = placeholder
    textField.backgroundColor = .white
    return textField
}
}

private extension UIStackView {
static func customStackView(_ orientation: NSLayoutConstraint.Axis, distribution: UIStackView.Distribution = UIStackView.Distribution.fill, backgroundColor: UIColor, subviews: [UIView]) -> UIStackView {
    let stackView = UIStackView(arrangedSubviews: subviews)
    stackView.axis = orientation
    stackView.distribution = .fillEqually
    stackView.backgroundColor = backgroundColor
    stackView.spacing = 5.0
    stackView.directionalLayoutMargins = NSDirectionalEdgeInsets(top: 2, leading: 2, bottom: 2, trailing: 2)
    stackView.isLayoutMarginsRelativeArrangement = true
    stackView.translatesAutoresizingMaskIntoConstraints = false
    return stackView
}

static func textFieldsStackView(_ title: String) -> UIStackView {
    let COLON = ":"
    let label = UILabel.customLabel(title)
    label.setContentHuggingPriority(.defaultHigh + 1, for: .horizontal)
    label.setContentHuggingPriority(.defaultHigh + 1, for: .vertical)
    let paceTextField1 = UITextField.customTextField("Hrs")
    let colonLabel1 = UILabel.customLabel(COLON)
    let paceTextField2 = UITextField.customTextField("Min")
    let colonLabel2 = UILabel.customLabel(COLON)
    let paceTextField3 = UITextField.customTextField("Sec")
    let textFieldContainerStackView = UIStackView.customStackView(.horizontal, backgroundColor: .systemPink, subviews: [paceTextField1, colonLabel1, paceTextField2, colonLabel2, paceTextField3])
    textFieldContainerStackView.setContentHuggingPriority(.defaultLow - 50, for: .horizontal)
    textFieldContainerStackView.setContentCompressionResistancePriority(.defaultLow - 1, for: .horizontal)
    return UIStackView.customStackView(.horizontal, distribution: .fill, backgroundColor: .systemBlue, subviews: [label, textFieldContainerStackView])
}

static func distanceStackView() -> UIStackView {
    let DISTANCE = "Distance"
    let label = UILabel.customLabel(DISTANCE)
    let distanceTextField = UITextField.customTextField(DISTANCE)
    return UIStackView.customStackView(.horizontal, distribution: .equalCentering, backgroundColor: .systemGray, subviews: [label, distanceTextField])
}

static func buttonStackView() -> UIStackView {
    let calculateButton = UIButton.customButton("Calculate")
    let resetButton = UIButton.customButton("Reset")
    return UIStackView.customStackView(.horizontal, backgroundColor: .green, subviews: [calculateButton, resetButton])
}
}

private extension UIButton {
static func customButton(_ title: String) -> UIButton {
    let button = UIButton()
    button.setTitle(title, for: .normal)
    return button
}
}

private extension UILabel {
static func customLabel(_ text: String) -> UILabel {
    let timeLabel = UILabel()
    timeLabel.text = text
    return timeLabel
}
}

【问题讨论】：

标签： ios swift autolayout uikit uistackview

【解决方案1】：

您可以在标签和 textfieldsStackview 之间添加一个透明的 UIView（所谓的间隔视图）并为其添加宽度约束。容器stackview（包含所有三个视图）的分布应该是.fill。

[UILabel][UIView][UIStackView]
[UILabel][UIView][UIStackView] 
[UILabel][UIView][UIStackView]

import UIKit

class RunningPaceCalculatorViewController: UIViewController {

    private lazy var timeDistancePaceStackView: UIStackView = {
        let timeStackView = UIStackView.textFieldsStackView("Time")
        let distanceStackView = UIStackView.distanceStackView()
        let paceStackView = UIStackView.textFieldsStackView("Pace")
        return UIStackView.customStackView(.vertical, backgroundColor: .systemTeal, subviews: [timeStackView, distanceStackView, paceStackView])
    }()

    private lazy var buttonStackView: UIStackView = {
        return UIStackView.buttonStackView()
    }()

    private lazy var constainerStackView: UIStackView = {
        return UIStackView.customStackView(.vertical, backgroundColor: .gray, subviews: [timeDistancePaceStackView, buttonStackView])
    }()

    override func viewDidLoad() {
        setUpView()
    }

    func setUpView() {
        view.backgroundColor = .orange
        view.addSubview(constainerStackView)

        NSLayoutConstraint.activate([
            constainerStackView.heightAnchor.constraint(equalTo: view.heightAnchor, multiplier: 0.55),
            constainerStackView.centerXAnchor.constraint(equalTo: view.centerXAnchor),
            constainerStackView.centerYAnchor.constraint(equalTo: view.centerYAnchor),
            constainerStackView.leadingAnchor.constraint(equalTo: view.leadingAnchor, constant: 10),
            constainerStackView.trailingAnchor.constraint(equalTo: view.trailingAnchor, constant: -10)
        ])
    }
}

private extension UITextField {
    static func customTextField(_ placeholder: String) -> UITextField {
        let textField = UITextField()
        textField.placeholder = placeholder
        textField.backgroundColor = .white
        return textField
    }
}

private extension UIStackView {
    static func customStackView(_ orientation: NSLayoutConstraint.Axis, distribution: UIStackView.Distribution = UIStackView.Distribution.fill, backgroundColor: UIColor, subviews: [UIView]) -> UIStackView {
        let stackView = UIStackView(arrangedSubviews: subviews)
        stackView.axis = orientation
        stackView.distribution = .fillEqually
        stackView.backgroundColor = backgroundColor
        stackView.spacing = 5.0
        stackView.directionalLayoutMargins = NSDirectionalEdgeInsets(top: 2, leading: 2, bottom: 2, trailing: 2)
        stackView.isLayoutMarginsRelativeArrangement = true
        stackView.translatesAutoresizingMaskIntoConstraints = false
        return stackView
    }

    static func textFieldsStackView(_ title: String) -> UIStackView {
        let COLON = ":"
        let label = UILabel.customLabel(title)
        label.translatesAutoresizingMaskIntoConstraints = false
        label.setContentHuggingPriority(.defaultHigh + 1, for: .horizontal)
        label.setContentHuggingPriority(.defaultHigh + 1, for: .vertical)

        let spacerView = UIView()
        spacerView.backgroundColor = .clear
        spacerView.translatesAutoresizingMaskIntoConstraints = false
        spacerView.widthAnchor.constraint(equalToConstant: 10).isActive = true

        let paceTextField1 = UITextField.customTextField("Hrs")
        paceTextField1.translatesAutoresizingMaskIntoConstraints = false
        let colonLabel1 = UILabel.customLabel(COLON)
        colonLabel1.translatesAutoresizingMaskIntoConstraints = false
        colonLabel1.widthAnchor.constraint(equalToConstant: 20).isActive = true

        let paceTextField2 = UITextField.customTextField("Min")
        paceTextField2.translatesAutoresizingMaskIntoConstraints = false
        let colonLabel2 = UILabel.customLabel(COLON)
        colonLabel2.translatesAutoresizingMaskIntoConstraints = false
        colonLabel2.widthAnchor.constraint(equalToConstant: 20).isActive = true

        let paceTextField3 = UITextField.customTextField("Sec")
        paceTextField3.translatesAutoresizingMaskIntoConstraints = false

        let textFieldContainerStackView = UIStackView.customStackView(.horizontal, backgroundColor: .systemPink, subviews: [paceTextField1, colonLabel1, paceTextField2, colonLabel2, paceTextField3])
        textFieldContainerStackView.setContentHuggingPriority(.defaultLow - 50, for: .horizontal)
        textFieldContainerStackView.setContentCompressionResistancePriority(.defaultLow - 1, for: .horizontal)
        textFieldContainerStackView.distribution = .fill

        paceTextField1.widthAnchor.constraint(equalTo: paceTextField2.widthAnchor).isActive = true
        paceTextField2.widthAnchor.constraint(equalTo: paceTextField3.widthAnchor).isActive = true

        let stackView = UIStackView.customStackView(.horizontal, distribution: .fill, backgroundColor: .systemBlue, subviews: [label, spacerView, textFieldContainerStackView])
        stackView.distribution = .fill
        return stackView
    }

    static func distanceStackView() -> UIStackView {
        let DISTANCE = "Distance"
        let label = UILabel.customLabel(DISTANCE)
        let distanceTextField = UITextField.customTextField(DISTANCE)
        return UIStackView.customStackView(.horizontal, distribution: .equalCentering, backgroundColor: .systemGray, subviews: [label, distanceTextField])
    }

    static func buttonStackView() -> UIStackView {
        let calculateButton = UIButton.customButton("Calculate")
        let resetButton = UIButton.customButton("Reset")
        return UIStackView.customStackView(.horizontal, backgroundColor: .green, subviews: [calculateButton, resetButton])
    }
}

private extension UIButton {
    static func customButton(_ title: String) -> UIButton {
        let button = UIButton()
        button.setTitle(title, for: .normal)
        return button
    }
}

private extension UILabel {
    static func customLabel(_ text: String) -> UILabel {
        let timeLabel = UILabel()
        timeLabel.text = text
        return timeLabel
    }
}

【讨论】：

您能举个例子吗？当我将分布设置为.fill 并添加一个间隔视图并添加一个像spacerView.widthAnchor.constraint(equalToConstant: 1) or 1,000,000 这样的约束时，它会在标签和文本字段之间产生更大的间隙

【解决方案2】：

拥有一个包含具有 AutoLayout 约束的常规 UIViews 的垂直堆栈视图可能更容易，然后让每个 UIViews 包含一个 UILabel 和另一个水平 UIStackView（或文本视图，用于第 2 行）。这样您就可以轻松控制标签和子视图的大小和间距。

【讨论】：

在界面构建器中做所有事情变得更加容易?

【解决方案3】：

创建“列”可能有点棘手......

根据你的图片和描述，我猜你想要这个（或至少接近这个）作为你的最终结果：

要做到这一点，需要做几件事：

将水平“行”堆栈视图上的分布设置为.fill
将水平“字段：字段：字段”堆栈视图上的分布设置为.fill
使用.multiplier为每个“标题”标签赋予一个等于其堆栈视图百分比的widthAnchor（赋予每个“行”相同的百分比值）
将“冒号”标签的 HUGGING 设置为 .required
将“min”和“sec”字段宽度限制设置为等于“hrs”字段宽度

这是您的代码，经过修改以生成我的屏幕截图。我尝试只更改必要的内容，并且我认为我包含了足够多的 cmets 以使其清楚：

class RunningPaceCalculatorViewController: UIViewController {
    
    // percent of overall width for Time/Distance/Pace "column" of labels
    private let labelWidth: CGFloat = 0.33
    
    private lazy var timeDistancePaceStackView: UIStackView = {
        // added titleWidth parameter -- percent of width of stack view
        let timeStackView = UIStackView.textFieldsStackView("Time", titleWidth: labelWidth)
        let distanceStackView = UIStackView.distanceStackView(labelWidth)
        let paceStackView = UIStackView.textFieldsStackView("Pace", titleWidth: labelWidth)
        // include setting distribution parameter
        return UIStackView.customStackView(.vertical, distribution: .fillEqually, backgroundColor: .systemTeal, subviews: [timeStackView, distanceStackView, paceStackView])
    }()
    
    private lazy var buttonStackView: UIStackView = {
        return UIStackView.buttonStackView()
    }()
    
    private lazy var constainerStackView: UIStackView = {
        // include setting distribution parameter
        return UIStackView.customStackView(.vertical, distribution: .fillEqually, backgroundColor: .gray, subviews: [timeDistancePaceStackView, buttonStackView])
    }()
    
    override func viewDidLoad() {
        setUpView()
    }
    
    func setUpView() {
        view.backgroundColor = .orange
        view.addSubview(constainerStackView)
        
        NSLayoutConstraint.activate([
            constainerStackView.heightAnchor.constraint(equalTo: view.heightAnchor, multiplier: 0.55),
            // we're setting Leading and Trailing, so we don't need centerX
            //constainerStackView.centerXAnchor.constraint(equalTo: view.centerXAnchor),
            constainerStackView.centerYAnchor.constraint(equalTo: view.centerYAnchor),
            constainerStackView.leadingAnchor.constraint(equalTo: view.leadingAnchor, constant: 10),
            constainerStackView.trailingAnchor.constraint(equalTo: view.trailingAnchor, constant: -10)
        ])
    }
}

private extension UITextField {
    static func customTextField(_ placeholder: String) -> UITextField {
        let textField = UITextField()
        textField.placeholder = placeholder
        textField.backgroundColor = .white
        return textField
    }
}

private extension UIStackView {
    static func customStackView(_ orientation: NSLayoutConstraint.Axis, distribution: UIStackView.Distribution = UIStackView.Distribution.fill, backgroundColor: UIColor, subviews: [UIView]) -> UIStackView {
        let stackView = UIStackView(arrangedSubviews: subviews)
        stackView.axis = orientation
        
        // use distribution parameter, not hard-coded .fillEqually
        //stackView.distribution = .fillEqually
        stackView.distribution = distribution
        
        stackView.backgroundColor = backgroundColor
        stackView.spacing = 5.0
        stackView.directionalLayoutMargins = NSDirectionalEdgeInsets(top: 2, leading: 2, bottom: 2, trailing: 2)
        stackView.isLayoutMarginsRelativeArrangement = true
        stackView.translatesAutoresizingMaskIntoConstraints = false
        return stackView
    }
    
    static func textFieldsStackView(_ title: String, titleWidth: CGFloat) -> UIStackView {
        let COLON = ":"
        let label = UILabel.customLabel(title)
        let paceTextField1 = UITextField.customTextField("Hrs")
        let colonLabel1 = UILabel.customLabel(COLON)
        let paceTextField2 = UITextField.customTextField("Min")
        let colonLabel2 = UILabel.customLabel(COLON)
        let paceTextField3 = UITextField.customTextField("Sec")
        // include setting distribution parameter
        let textFieldContainerStackView = UIStackView.customStackView(.horizontal, distribution: .fill, backgroundColor: .systemPink, subviews: [paceTextField1, colonLabel1, paceTextField2, colonLabel2, paceTextField3])
        
        // create the stack view to return
        let retStack = UIStackView.customStackView(.horizontal, distribution: .fill, backgroundColor: .systemBlue, subviews: [label, textFieldContainerStackView])
        // colon labels should HUG their content
        colonLabel1.setContentHuggingPriority(.required, for: .horizontal)
        colonLabel2.setContentHuggingPriority(.required, for: .horizontal)
        NSLayoutConstraint.activate([
            // constrain "title label" width to percentage of stack view width
            label.widthAnchor.constraint(equalTo: retStack.widthAnchor, multiplier: titleWidth),
            // constrain text field widths to each other
            paceTextField2.widthAnchor.constraint(equalTo: paceTextField1.widthAnchor),
            paceTextField3.widthAnchor.constraint(equalTo: paceTextField1.widthAnchor),
        ])
        return retStack
    }
    
    static func distanceStackView(_ titleWidth: CGFloat) -> UIStackView {
        let DISTANCE = "Distance"
        let label = UILabel.customLabel(DISTANCE)
        let distanceTextField = UITextField.customTextField(DISTANCE)

        // create the stack view to return
        let retStack = UIStackView.customStackView(.horizontal, distribution: .fill, backgroundColor: .systemGray, subviews: [label, distanceTextField])
        NSLayoutConstraint.activate([
            // constrain "title label" width to percentage of stack view width
            label.widthAnchor.constraint(equalTo: retStack.widthAnchor, multiplier: titleWidth),
        ])
        return retStack
    }
    
    static func buttonStackView() -> UIStackView {
        let calculateButton = UIButton.customButton("Calculate")
        let resetButton = UIButton.customButton("Reset")
        // include setting distribution parameter
        return UIStackView.customStackView(.horizontal, distribution: .fillEqually, backgroundColor: .green, subviews: [calculateButton, resetButton])
    }
}

private extension UIButton {
    static func customButton(_ title: String) -> UIButton {
        let button = UIButton()
        button.setTitle(title, for: .normal)
        return button
    }
}

private extension UILabel {
    static func customLabel(_ text: String) -> UILabel {
        let timeLabel = UILabel()
        timeLabel.text = text
        return timeLabel
    }
}

【讨论】：