Factory for simplifying UIKit views creation from code.

ViewFactory.swift

import UIKit

public struct ViewFactory {
    public static var labelColor: UIColor = .black
    public static var secondaryLabelColor: UIColor = .gray
    public static var labelFont: UIFont = .systemFont(ofSize: 15, weight: .medium)
    public static var fieldFont: UIFont = .systemFont(ofSize: 15, weight: .semibold)

    public static func view(
        _ backgroundColor: UIColor? = UIColor.clear,
        corners: CACornerMask? = nil,
        radius: CGFloat = 0
    ) -> UIView {
        let view = UIView()
        view.translatesAutoresizingMaskIntoConstraints = false
        view.layer.cornerRadius = radius
        corners.flatMap { view.layer.maskedCorners = $0 }
        backgroundColor.flatMap { view.backgroundColor = $0 }
        return view
    }
    
    public static func label(
        _ color: UIColor? = labelColor,
        font: UIFont? = labelFont,
        adjustsFontSizeToFitWidth: Bool = true,
        align: NSTextAlignment = .left,
        lines: Int = 0,
        breakMode: NSLineBreakMode = .byWordWrapping,
        minimumScaleMultiplier: CGFloat? = 0.8,
        text: String = ""
    ) -> UILabel {
        let view = UILabel()
        view.text = text
        view.translatesAutoresizingMaskIntoConstraints = false
        font.flatMap { view.font = $0 }
        color.flatMap { view.textColor = $0 }
        view.numberOfLines = 0
        view.lineBreakMode = breakMode
        view.textAlignment = align
        view.numberOfLines = lines
        view.adjustsFontSizeToFitWidth = adjustsFontSizeToFitWidth

        if let scale = minimumScaleMultiplier {
            view.allowsDefaultTighteningForTruncation = true
            view.minimumScaleFactor = scale
        }

        return view
    }
    
    public static func textField(
        hint: String = "",
        textColor: UIColor? = labelColor,
        font: UIFont? = fieldFont,
        hintColor: UIColor? = secondaryLabelColor
    ) -> UITextField {
        let view = UITextField()
        view.translatesAutoresizingMaskIntoConstraints = false
        view.font = font
        textColor.flatMap { view.textColor = $0 }

        hintColor.flatMap {
            view.attributedPlaceholder = NSAttributedString(
                string: hint,
                attributes: [.foregroundColor: $0]
            )
        }
        return view
    }

    public static func scroll(delegate: UIScrollViewDelegate? = nil) -> UIScrollView {
        let view = UIScrollView()
        view.translatesAutoresizingMaskIntoConstraints = false
        view.delegate = delegate
        return view
    }
    
    public static func table() -> UITableView {
        let view = UITableView()
        view.translatesAutoresizingMaskIntoConstraints = false
        return view
    }
    
    public static func stack(
        _ spacing: CGFloat = 0,
        margins: NSDirectionalEdgeInsets = .zero,
        axis: NSLayoutConstraint.Axis = .vertical,
        align: UIStackView.Alignment = .fill,
        distrib: UIStackView.Distribution = .fill,
        subviews: [UIView] = []
    ) -> UIStackView {
        let view = UIStackView(arrangedSubviews: subviews)
        view.translatesAutoresizingMaskIntoConstraints = false
        view.spacing = spacing
        view.distribution = distrib
        view.alignment = align
        view.axis = axis

        view.isLayoutMarginsRelativeArrangement = true
        view.directionalLayoutMargins = margins
        return view
    }

    public static func image(
        _ imageName: String? = nil,
        image: UIImage? = nil,
        tint: UIColor? = nil,
        contentMode: UIView.ContentMode = .scaleAspectFit
    ) -> UIImageView {
        let view = UIImageView()
        view.translatesAutoresizingMaskIntoConstraints = false
        view.contentMode = contentMode
        imageName.flatMap { view.image = UIImage(named: $0) }
        image.flatMap { view.image = $0 }
        tint.flatMap { view.tintColor = $0 }
        return view
    }
}

public extension CACornerMask {
    static let top: CACornerMask = [.layerMinXMinYCorner, .layerMaxXMinYCorner]
    static let bottom: CACornerMask = [.layerMinXMaxYCorner, .layerMaxXMaxYCorner]
    static let all: CACornerMask = top.union(bottom)
    static let none: CACornerMask = []
}