Action Sheet Presentation Controller

README.md

Action Sheet Presentation Controller

Use any view controller in an action sheet. This is not worthy of a dedicated pod or a framework. Please don't make it one.

Usage

Return an ActionSheetPresentationController from presentationController(forPresented:presenting:) and make sure the presented view controller's view has a measurable Auto Layout size.

To-Dos

• Respect preferredContentSize instead of only Auto Layout size
• Adapt to regular width by switching to a popover presentation
• Switch to a normal UIButton instead of a custom dismiss button.

ActionSheetPresentationController.swift

//  Created by Caleb Davenport on 7/14/17.

import UIKit

final class ActionSheetPresentationController: UIPresentationController {

    // MARK: - Properties

    private var dimmingView: UIView!

    private var customPresentedView: UIView!

    override var presentedView: UIView? {
        return customPresentedView
    }

    override var frameOfPresentedViewInContainerView: CGRect {
        let size = customPresentedView.systemLayoutSizeFitting(
            containerView!.bounds.size,
            withHorizontalFittingPriority: UILayoutPriorityRequired,
            verticalFittingPriority: UILayoutPriorityFittingSizeLevel)

        let (slice, _) = containerView!.bounds.divided(atDistance: size.height, from: .maxYEdge)

        return slice
    }


    // MARK: - UIPresentationController

    override func presentationTransitionWillBegin() {
        super.presentationTransitionWillBegin()

        if dimmingView == nil {
            dimmingView = UIView()
            dimmingView.backgroundColor = UIColor(white: 0, alpha: 0.4)

            let cancelGestureRecognizer = UITapGestureRecognizer(target: self, action: #selector(cancel))
            dimmingView.addGestureRecognizer(cancelGestureRecognizer)

            dimmingView.autoresizingMask = [.flexibleWidth, .flexibleHeight]
            dimmingView.frame = containerView!.bounds
            containerView!.addSubview(dimmingView)
        }

        if customPresentedView == nil {
            let dismissButton = ActionSheetPresentationControllerDismissButton()
            dismissButton.addTarget(self, action: #selector(cancel), for: .touchUpInside)
            dismissButton.setContentHuggingPriority(UILayoutPriorityDefaultHigh, for: .vertical)

            let dismissButtonSectionView = ActionSheetPresentationControllerSectionView()
            dismissButton.translatesAutoresizingMaskIntoConstraints = false
            dismissButtonSectionView.addSubview(dismissButton)

            let presentedViewControllerSectionView = ActionSheetPresentationControllerSectionView()
            presentedViewController.view.translatesAutoresizingMaskIntoConstraints = false
            presentedViewControllerSectionView.addSubview(presentedViewController.view)

            NSLayoutConstraint.activate([
                dismissButton.leadingAnchor.constraint(equalTo: dismissButtonSectionView.leadingAnchor),
                dismissButton.trailingAnchor.constraint(equalTo: dismissButtonSectionView.trailingAnchor),
                dismissButton.topAnchor.constraint(equalTo: dismissButtonSectionView.topAnchor),
                dismissButton.bottomAnchor.constraint(equalTo: dismissButtonSectionView.bottomAnchor),

                presentedViewController.view.leadingAnchor.constraint(equalTo: presentedViewControllerSectionView.leadingAnchor),
                presentedViewController.view.trailingAnchor.constraint(equalTo: presentedViewControllerSectionView.trailingAnchor),
                presentedViewController.view.topAnchor.constraint(equalTo: presentedViewControllerSectionView.topAnchor),
                presentedViewController.view.bottomAnchor.constraint(equalTo: presentedViewControllerSectionView.bottomAnchor)])

            let stackView = UIStackView(arrangedSubviews: [presentedViewControllerSectionView, dismissButtonSectionView])
            stackView.autoresizingMask = [.flexibleWidth, .flexibleTopMargin]
            stackView.axis = .vertical
            stackView.isLayoutMarginsRelativeArrangement = true
            stackView.spacing = 10
            stackView.layoutMargins = UIEdgeInsets(top: 10, left: 10, bottom: 10, right: 10)

            customPresentedView = stackView
        }

        dimmingView.alpha = 0

        presentedViewController.transitionCoordinator?.animate(alongsideTransition: { _ in
            self.dimmingView.alpha = 1
        })
    }

    override func dismissalTransitionWillBegin() {
        presentedViewController.transitionCoordinator?.animate(alongsideTransition: { _ in
            self.dimmingView.alpha = 0
        })
    }

    override func viewWillTransition(to size: CGSize, with coordinator: UIViewControllerTransitionCoordinator) {
        super.viewWillTransition(to: size, with: coordinator)

        coordinator.animate(alongsideTransition: { _ in
            self.customPresentedView.frame = self.frameOfPresentedViewInContainerView
        })
    }


    // MARK: - Private

    @objc private func cancel() {
        presentedViewController.dismiss(animated: true, completion: nil)
    }
}

ActionSheetPresentationControllerDismissButton.swift

//  Created by Caleb Davenport on 7/14/17.

import UIKit

final class ActionSheetPresentationControllerDismissButton: UIControl {

    // MARK: - Properties

    private let textLabel: UILabel = {
        let view = UILabel()
        view.font = UIFont.systemFont(ofSize: 20, weight: UIFontWeightSemibold)
        view.text = L10n.General.done.localizedCapitalized
        view.textAlignment = .center
        return view
    }()

    override var intrinsicContentSize: CGSize {
        return CGSize(width: UIViewNoIntrinsicMetric, height: 57)
    }


    // MARK: - Initializers

    override init(frame: CGRect) {
        super.init(frame: frame)
        setup()
    }

    required init?(coder: NSCoder) {
        super.init(coder: coder)
        setup()
    }


    // MARK: - UIView

    override func layoutSubviews() {
        super.layoutSubviews()
        textLabel.frame = bounds
    }

    override func tintColorDidChange() {
        super.tintColorDidChange()
        textLabel.textColor = tintColor
    }


    // MARK: - Private

    private func setup() {
        textLabel.textColor = tintColor
        addSubview(textLabel)
    }
}

ActionSheetPresentationControllerSectionView.swift

//  Created by Caleb Davenport on 7/14/17.

import UIKit

final class ActionSheetPresentationControllerSectionView: UIView {

    // MARK: - Properties

    private let visualEffectView = UIVisualEffectView(effect: UIBlurEffect(style: .extraLight))


    // MARK: - Initializers

    override init(frame: CGRect) {
        super.init(frame: frame)
        setup()
    }

    required init?(coder: NSCoder) {
        super.init(coder: coder)
        setup()
    }


    override func layoutSubviews() {
        super.layoutSubviews()
        visualEffectView.frame = bounds
    }


    // MARK: - Private

    private func setup() {
        layer.masksToBounds = true
        layer.cornerRadius = 14

        visualEffectView.isUserInteractionEnabled = false

        addSubview(visualEffectView)
    }
}

DatePickerViewController.swift

//  Created by Caleb Davenport on 7/14/17.

import UIKit

final class DatePickerViewController: UIViewController {

    // MARK: - Properties

    let datePicker = UIDatePicker()


    // MARK: - Initializers

    init() {
        super.init(nibName: nil, bundle: nil)
        modalPresentationStyle = .custom
        transitioningDelegate = self
    }

    @available(*, unavailable)
    required init?(coder: NSCoder) {
        unimplemented()
    }


    // MARK: - UIViewController

    override func viewDidLoad() {
        super.viewDidLoad()

        datePicker.translatesAutoresizingMaskIntoConstraints = false
        view.addSubview(datePicker)

        NSLayoutConstraint.activate([
            datePicker.leadingAnchor.constraint(equalTo: view.leadingAnchor),
            datePicker.trailingAnchor.constraint(equalTo: view.trailingAnchor),
            datePicker.topAnchor.constraint(equalTo: view.topAnchor),
            datePicker.bottomAnchor.constraint(equalTo: view.bottomAnchor)])
    }
}

extension DatePickerViewController: UIViewControllerTransitioningDelegate {
    func presentationController(forPresented presented: UIViewController, presenting: UIViewController?, source: UIViewController) -> UIPresentationController? {
        return ActionSheetPresentationController(presentedViewController: presented, presenting: presenting)
    }
}