Add completion block to present function (#94)

* Add ability to customize drag indicator background color

* Add default dragIndicatorBackgroundColor test

* update PR according to comments

Package.swift

@@ -0,0 +1,22 @@
+// swift-tools-version:5.1
+// The swift-tools-version declares the minimum version of Swift required to build this package.
+
+import PackageDescription
+
+let package = Package(
+    name: "PanModal",
+    platforms: [.iOS(.v10)],
+    products: [
+        .library(
+            name: "PanModal",
+            targets: ["PanModal"]),
+    ],
+    dependencies: [],
+    targets: [
+        .target(
+            name: "PanModal",
+            dependencies: [],
+            path: "PanModal")
+    ],
+    swiftLanguageVersions: [.version("5.0")]
+)

PanModal.podspec

@@ -8,7 +8,7 @@
 
 Pod::Spec.new do |s|
   s.name             = 'PanModal'
-  s.version          = '1.2.2'
+  s.version          = '1.2.7'
   s.summary          = 'PanModal is an elegant and highly customizable presentation API for constructing bottom sheet modals on iOS.'
 
 # This description is used to generate tags and improve search results.
@@ -24,6 +24,6 @@ Pod::Spec.new do |s|
   s.source           = { :git => 'https://github.com/slackhq/PanModal.git', :tag => s.version.to_s }
   s.social_media_url = 'https://twitter.com/slackhq'
   s.ios.deployment_target = '10.0'
-  s.swift_version = '4.2'
+  s.swift_version = '5.0'
   s.source_files = 'PanModal/**/*.{swift,h,m}'
 end

PanModal/Animator/PanModalAnimator.swift

@@ -5,6 +5,7 @@
 //  Copyright © 2019 Tiny Speck, Inc. All rights reserved.
 //
 
+#if os(iOS)
 import UIKit
 
 /**
@@ -16,19 +17,24 @@ struct PanModalAnimator {
      Constant Animation Properties
      */
     struct Constants {
-        static let transitionDuration: TimeInterval = 0.5
+        static let defaultTransitionDuration: TimeInterval = 0.5
     }
 
     static func animate(_ animations: @escaping PanModalPresentable.AnimationBlockType,
                         config: PanModalPresentable?,
                         _ completion: PanModalPresentable.AnimationCompletionType? = nil) {
 
-        UIView.animate(withDuration: Constants.transitionDuration,
+        let transitionDuration = config?.transitionDuration ?? Constants.defaultTransitionDuration
+        let springDamping = config?.springDamping ?? 1.0
+        let animationOptions = config?.transitionAnimationOptions ?? []
+
+        UIView.animate(withDuration: transitionDuration,
                        delay: 0,
-                       usingSpringWithDamping: config?.springDamping ?? 1.0,
+                       usingSpringWithDamping: springDamping,
                        initialSpringVelocity: 0,
-                       options: [.curveEaseInOut, .allowUserInteraction, .beginFromCurrentState],
+                       options: animationOptions,
                        animations: animations,
                        completion: completion)
     }
 }
+#endif

PanModal/Animator/PanModalPresentationAnimator.swift

@@ -5,6 +5,7 @@
 //  Copyright © 2019 Tiny Speck, Inc. All rights reserved.
 //
 
+#if os(iOS)
 import UIKit
 
 /**
@@ -63,11 +64,16 @@ public class PanModalPresentationAnimator: NSObject {
      */
     private func animatePresentation(transitionContext: UIViewControllerContextTransitioning) {
 
-        guard let toVC = transitionContext.viewController(forKey: .to)
+        guard
+            let toVC = transitionContext.viewController(forKey: .to),
+            let fromVC = transitionContext.viewController(forKey: .from)
             else { return }
 
-        let presentable = toVC as? PanModalPresentable.LayoutType
+        let presentable = panModalLayoutType(from: transitionContext)
 
+        // Calls viewWillAppear and viewWillDisappear
+        fromVC.beginAppearanceTransition(false, animated: true)
+        
         // Presents the view in shortForm position, initially
         let yPos: CGFloat = presentable?.shortFormYPos ?? 0.0
 
@@ -86,6 +92,8 @@ public class PanModalPresentationAnimator: NSObject {
         PanModalAnimator.animate({
             panView.frame.origin.y = yPos
         }, config: presentable) { [weak self] didComplete in
+            // Calls viewDidAppear and viewDidDisappear
+            fromVC.endAppearanceTransition()
             transitionContext.completeTransition(didComplete)
             self?.feedbackGenerator = nil
         }
@@ -96,20 +104,39 @@ public class PanModalPresentationAnimator: NSObject {
      */
     private func animateDismissal(transitionContext: UIViewControllerContextTransitioning) {
 
-        guard let fromVC = transitionContext.viewController(forKey: .from)
+        guard
+            let toVC = transitionContext.viewController(forKey: .to),
+            let fromVC = transitionContext.viewController(forKey: .from)
             else { return }
 
-        let presentable = fromVC as? PanModalPresentable.LayoutType
+        // Calls viewWillAppear and viewWillDisappear
+        toVC.beginAppearanceTransition(true, animated: true)
+        
+        let presentable = panModalLayoutType(from: transitionContext)
         let panView: UIView = transitionContext.containerView.panContainerView ?? fromVC.view
 
         PanModalAnimator.animate({
             panView.frame.origin.y = transitionContext.containerView.frame.height
         }, config: presentable) { didComplete in
             fromVC.view.removeFromSuperview()
+            // Calls viewDidAppear and viewDidDisappear
+            toVC.endAppearanceTransition()
             transitionContext.completeTransition(didComplete)
         }
     }
 
+    /**
+     Extracts the PanModal from the transition context, if it exists
+     */
+    private func panModalLayoutType(from context: UIViewControllerContextTransitioning) -> PanModalPresentable.LayoutType? {
+        switch transitionStyle {
+        case .presentation:
+            return context.viewController(forKey: .to) as? PanModalPresentable.LayoutType
+        case .dismissal:
+            return context.viewController(forKey: .from) as? PanModalPresentable.LayoutType
+        }
+    }
+
 }
 
 // MARK: - UIViewControllerAnimatedTransitioning Delegate
@@ -120,7 +147,13 @@ extension PanModalPresentationAnimator: UIViewControllerAnimatedTransitioning {
      Returns the transition duration
      */
     public func transitionDuration(using transitionContext: UIViewControllerContextTransitioning?) -> TimeInterval {
-        return PanModalAnimator.Constants.transitionDuration
+
+        guard
+            let context = transitionContext,
+            let presentable = panModalLayoutType(from: context)
+            else { return PanModalAnimator.Constants.defaultTransitionDuration }
+
+        return presentable.transitionDuration
     }
 
     /**
@@ -136,3 +169,4 @@ extension PanModalPresentationAnimator: UIViewControllerAnimatedTransitioning {
     }
 
 }
+#endif

PanModal/Controller/PanModalPresentationController.swift

@@ -5,6 +5,7 @@
 //  Copyright © 2019 Tiny Speck, Inc. All rights reserved.
 //
 
+#if os(iOS)
 import UIKit
 
 /**
@@ -22,7 +23,7 @@ import UIKit
  By conforming to the PanModalPresentable protocol & overriding values
  the presented view can define its layout configuration & presentation.
  */
-public class PanModalPresentationController: UIPresentationController {
+open class PanModalPresentationController: UIPresentationController {
 
     /**
      Enum representing the possible presentation states
@@ -105,13 +106,15 @@ public class PanModalPresentationController: UIPresentationController {
      */
     private lazy var backgroundView: DimmedView = {
         let view: DimmedView
-        if let alpha = presentable?.backgroundAlpha {
-            view = DimmedView(dimAlpha: alpha)
+        if let color = presentable?.panModalBackgroundColor {
+            view = DimmedView(dimColor: color)
         } else {
             view = DimmedView()
         }
         view.didTap = { [weak self] _ in
-            self?.dismissPresentedViewController()
+            if self?.presentable?.allowsTapToDismiss == true {
+                self?.presentedViewController.dismiss(animated: true)
+            }
         }
         return view
     }()
@@ -131,7 +134,7 @@ public class PanModalPresentationController: UIPresentationController {
      */
     private lazy var dragIndicatorView: UIView = {
         let view = UIView()
-        view.backgroundColor = .lightGray
+        view.backgroundColor = presentable?.dragIndicatorBackgroundColor
         view.layer.cornerRadius = Constants.dragIndicatorSize.height / 2.0
         return view
     }()
@@ -189,7 +192,14 @@ public class PanModalPresentationController: UIPresentationController {
         })
     }
 
+    override public func presentationTransitionDidEnd(_ completed: Bool) {
+        if completed { return }
+
+        backgroundView.removeFromSuperview()
+    }
+
     override public func dismissalTransitionWillBegin() {
+        presentable?.panModalWillDismiss()
 
         guard let coordinator = presentedViewController.transitionCoordinator else {
             backgroundView.dimState = .off
@@ -207,10 +217,29 @@ public class PanModalPresentationController: UIPresentationController {
         })
     }
 
-    override public func presentationTransitionDidEnd(_ completed: Bool) {
-        if completed { return }
+    override public func dismissalTransitionDidEnd(_ completed: Bool) {
+        if !completed { return }
+        
+        presentable?.panModalDidDismiss()
+    }
 
-        backgroundView.removeFromSuperview()
+    /**
+     Update presented view size in response to size class changes
+     */
+    override public func viewWillTransition(to size: CGSize, with coordinator: UIViewControllerTransitionCoordinator) {
+        super.viewWillTransition(to: size, with: coordinator)
+
+        coordinator.animate(alongsideTransition: { [weak self] _ in
+            guard
+                let self = self,
+                let presentable = self.presentable
+                else { return }
+
+            self.adjustPresentedViewFrame()
+            if presentable.shouldRoundTopCorners {
+                self.addRoundedCorners(to: self.presentedView)
+            }
+        })
     }
 
 }
@@ -223,7 +252,7 @@ public extension PanModalPresentationController {
      Transition the PanModalPresentationController
      to the given presentation state
      */
-    public func transition(to state: PresentationState) {
+    func transition(to state: PresentationState) {
 
         guard presentable?.shouldTransition(to: state) == true
             else { return }
@@ -239,35 +268,27 @@ public extension PanModalPresentationController {
     }
 
     /**
-     Set the content offset of the scroll view
+     Operations on the scroll view, such as content height changes,
+     or when inserting/deleting rows can cause the pan modal to jump,
+     caused by the pan modal responding to content offset changes.
 
-     Due to content offset observation, its not possible to programmatically
-     set the content offset directly on the scroll view while in the short form.
-
-     This method pauses the content offset KVO, performs the content offset change
-     and then resumes content offset observation.
+     To avoid this, you can call this method to perform scroll view updates,
+     with scroll observation temporarily disabled.
      */
-    public func setContentOffset(offset: CGPoint) {
+    func performUpdates(_ updates: () -> Void) {
 
         guard let scrollView = presentable?.panScrollable
             else { return }
 
-        /**
-         Invalidate scroll view observer
-         to prevent its overriding the content offset change
-         */
+        // Pause scroll observer
         scrollObserver?.invalidate()
         scrollObserver = nil
 
-        /**
-         Set scroll view offset & track scrolling
-         */
-        scrollView.setContentOffset(offset, animated:false)
-        trackScrolling(scrollView)
+        // Perform updates
+        updates()
 
-        /**
-         Add the scroll view observer
-         */
+        // Resume scroll observer
+        trackScrolling(scrollView)
         observe(scrollView: scrollView)
     }
 
@@ -278,7 +299,7 @@ public extension PanModalPresentationController {
      - Note: This should be called whenever any
      pan modal presentable value changes after the initial presentation
      */
-    public func setNeedsLayoutUpdate() {
+    func setNeedsLayoutUpdate() {
         configureViewLayout()
         adjustPresentedViewFrame()
         observe(scrollView: presentable?.panScrollable)
@@ -297,7 +318,7 @@ private extension PanModalPresentationController {
     var isPresentedViewAnchored: Bool {
         if !isPresentedViewAnimating
             && extendsPanScrolling
-            && presentedView.frame.minY <= anchoredYPosition {
+            && presentedView.frame.minY.rounded() <= anchoredYPosition.rounded() {
             return true
         }
 
@@ -342,9 +363,22 @@ private extension PanModalPresentationController {
      Reduce height of presentedView so that it sits at the bottom of the screen
      */
     func adjustPresentedViewFrame() {
-        let frame = containerView?.frame ?? .zero
-        let size = CGSize(width: frame.size.width, height: frame.height - anchoredYPosition)
-        presentedViewController.view.frame = CGRect(origin: .zero, size: size)
+
+        guard let frame = containerView?.frame
+            else { return }
+
+        let adjustedSize = CGSize(width: frame.size.width, height: frame.size.height - anchoredYPosition)
+        let panFrame = panContainerView.frame
+        panContainerView.frame.size = frame.size
+        
+        if ![shortFormYPosition, longFormYPosition].contains(panFrame.origin.y) {
+            // if the container is already in the correct position, no need to adjust positioning
+            // (rotations & size changes cause positioning to be out of sync)
+            let yPosition = panFrame.origin.y - panFrame.height + frame.height
+            presentedView.frame.origin.y = max(yPosition, anchoredYPosition)
+        }
+        panContainerView.frame.origin.x = frame.origin.x
+        presentedViewController.view.frame = CGRect(origin: .zero, size: adjustedSize)
     }
 
     /**
@@ -489,7 +523,7 @@ private extension PanModalPresentationController {
                     transition(to: .shortForm)
 
                 } else {
-                    dismissPresentedViewController()
+                    presentedViewController.dismiss(animated: true)
                 }
 
             } else {
@@ -507,7 +541,7 @@ private extension PanModalPresentationController {
                     transition(to: .shortForm)
 
                 } else {
-                    dismissPresentedViewController()
+                    presentedViewController.dismiss(animated: true)
                 }
             }
         }
@@ -646,14 +680,6 @@ private extension PanModalPresentationController {
             else { return number }
         return nearestVal
     }
-
-    /**
-     Dismiss presented view
-     */
-    func dismissPresentedViewController() {
-        presentable?.panModalWillDismiss()
-        presentedViewController.dismiss(animated: true, completion: nil)
-    }
 }
 
 // MARK: - UIScrollView Observer
@@ -758,7 +784,7 @@ private extension PanModalPresentationController {
      */
     func handleScrollViewTopBounce(scrollView: UIScrollView, change: NSKeyValueObservedChange<CGPoint>) {
 
-        guard let oldYValue = change.oldValue?.y
+        guard let oldYValue = change.oldValue?.y, scrollView.isDecelerating
             else { return }
 
         let yOffset = scrollView.contentOffset.y
@@ -798,11 +824,11 @@ extension PanModalPresentationController: UIGestureRecognizerDelegate {
     }
 
     /**
-     Allow simultaneous gesture recognizers only when the other gesture recognizer
-     is a pan gesture recognizer
+     Allow simultaneous gesture recognizers only when the other gesture recognizer's view
+     is the pan scrollable view
      */
     public func gestureRecognizer(_ gestureRecognizer: UIGestureRecognizer, shouldRecognizeSimultaneouslyWith otherGestureRecognizer: UIGestureRecognizer) -> Bool {
-        return otherGestureRecognizer.isKind(of: UIPanGestureRecognizer.self)
+        return otherGestureRecognizer.view == presentable?.panScrollable
     }
 }
 
@@ -863,3 +889,4 @@ private extension UIScrollView {
         return isDragging && !isDecelerating || isTracking
     }
 }
+#endif

PanModal/Delegate/PanModalPresentationDelegate.swift

@@ -5,6 +5,7 @@
 //  Copyright © 2019 Tiny Speck, Inc. All rights reserved.
 //
 
+#if os(iOS)
 import UIKit
 
 /**
@@ -73,8 +74,8 @@ extension PanModalPresentationDelegate: UIAdaptivePresentationControllerDelegate
      Dismisses the presented view controller
      */
     public func adaptivePresentationStyle(for controller: UIPresentationController, traitCollection: UITraitCollection) -> UIModalPresentationStyle {
-        controller.presentedViewController.dismiss(animated: false, completion: nil)
         return .none
     }
 
 }
+#endif

PanModal/Presentable/PanModalHeight.swift

@@ -5,6 +5,7 @@
 //  Copyright © 2019 Tiny Speck, Inc. All rights reserved.
 //
 
+#if os(iOS)
 import UIKit
 
 /**
@@ -40,3 +41,4 @@ public enum PanModalHeight: Equatable {
      */
     case intrinsicHeight
 }
+#endif

PanModal/Presentable/PanModalPresentable+Defaults.swift

@@ -5,6 +5,7 @@
 //  Copyright © 2018 Tiny Speck, Inc. All rights reserved.
 //
 
+#if os(iOS)
 import UIKit
 
 /**
@@ -38,8 +39,20 @@ public extension PanModalPresentable where Self: UIViewController {
         return 0.8
     }
 
-    var backgroundAlpha: CGFloat {
-        return 0.7
+    var transitionDuration: Double {
+        return PanModalAnimator.Constants.defaultTransitionDuration
+    }
+
+    var transitionAnimationOptions: UIView.AnimationOptions {
+        return [.curveEaseInOut, .allowUserInteraction, .beginFromCurrentState]
+    }
+
+    var panModalBackgroundColor: UIColor {
+        return UIColor.black.withAlphaComponent(0.7)
+    }
+
+    var dragIndicatorBackgroundColor: UIColor {
+        return UIColor.lightGray
     }
 
     var scrollIndicatorInsets: UIEdgeInsets {
@@ -64,6 +77,10 @@ public extension PanModalPresentable where Self: UIViewController {
         return true
     }
 
+    var allowsTapToDismiss: Bool {
+        return true
+    }
+
     var isUserInteractionEnabled: Bool {
         return true
     }
@@ -104,4 +121,8 @@ public extension PanModalPresentable where Self: UIViewController {
 
     }
 
+    func panModalDidDismiss() {
+
+    }
 }
+#endif

PanModal/Presentable/PanModalPresentable+LayoutHelpers.swift

@@ -5,6 +5,7 @@
 //  Copyright © 2018 Tiny Speck, Inc. All rights reserved.
 //
 
+#if os(iOS)
 import UIKit
 
 /**
@@ -26,7 +27,11 @@ extension PanModalPresentable where Self: UIViewController {
      Gives us the safe area inset from the top.
      */
     var topLayoutOffset: CGFloat {
-        return UIApplication.shared.keyWindow?.rootViewController?.topLayoutGuide.length ?? 0
+
+        guard let rootVC = rootViewController
+            else { return 0}
+
+        if #available(iOS 11.0, *) { return rootVC.view.safeAreaInsets.top } else { return rootVC.topLayoutGuide.length }
     }
 
     /**
@@ -34,7 +39,11 @@ extension PanModalPresentable where Self: UIViewController {
      Gives us the safe area inset from the bottom.
      */
     var bottomLayoutOffset: CGFloat {
-        return UIApplication.shared.keyWindow?.rootViewController?.bottomLayoutGuide.length ?? 0
+
+       guard let rootVC = rootViewController
+            else { return 0}
+
+        if #available(iOS 11.0, *) { return rootVC.view.safeAreaInsets.bottom } else { return rootVC.bottomLayoutGuide.length }
     }
 
     /**
@@ -99,4 +108,13 @@ extension PanModalPresentable where Self: UIViewController {
         }
     }
 
+    private var rootViewController: UIViewController? {
+
+        guard let application = UIApplication.value(forKeyPath: #keyPath(UIApplication.shared)) as? UIApplication
+            else { return nil }
+
+        return application.keyWindow?.rootViewController
+    }
+
 }
+#endif

PanModal/Presentable/PanModalPresentable+UIViewController.swift

@@ -5,6 +5,7 @@
 //  Copyright © 2018 Tiny Speck, Inc. All rights reserved.
 //
 
+#if os(iOS)
 import UIKit
 
 /**
@@ -29,16 +30,6 @@ public extension PanModalPresentable where Self: UIViewController {
         presentedVC?.transition(to: state)
     }
 
-    /**
-     Programmatically set the content offset of the pan scrollable.
-
-     This is required to use while in the short form presentation state,
-     as due to content offset observation, setting the content offset directly would fail
-     */
-    func panModalSetContentOffset(offset: CGPoint) {
-        presentedVC?.setContentOffset(offset: offset)
-    }
-
     /**
      A function wrapper over the `setNeedsLayoutUpdate()`
      function in the PanModalPresentationController.
@@ -49,6 +40,16 @@ public extension PanModalPresentable where Self: UIViewController {
         presentedVC?.setNeedsLayoutUpdate()
     }
 
+    /**
+     Operations on the scroll view, such as content height changes, or when inserting/deleting rows can cause the pan modal to jump,
+     caused by the pan modal responding to content offset changes.
+
+     To avoid this, you can call this method to perform scroll view updates, with scroll observation temporarily disabled.
+     */
+    func panModalPerformUpdates(_ updates: () -> Void) {
+        presentedVC?.performUpdates(updates)
+    }
+
     /**
      A function wrapper over the animate function in PanModalAnimator.
 
@@ -59,3 +60,4 @@ public extension PanModalPresentable where Self: UIViewController {
     }
 
 }
+#endif

PanModal/Presentable/PanModalPresentable.swift

@@ -5,6 +5,7 @@
 //  Copyright © 2017 Tiny Speck, Inc. All rights reserved.
 //
 
+#if os(iOS)
 import UIKit
 
 /**
@@ -18,7 +19,7 @@ import UIKit
  }
  ```
  */
-public protocol PanModalPresentable {
+public protocol PanModalPresentable: AnyObject {
 
     /**
      The scroll view embedded in the view controller.
@@ -70,13 +71,36 @@ public protocol PanModalPresentable {
     var springDamping: CGFloat { get }
 
     /**
-     The background view alpha.
+     The transitionDuration value is used to set the speed of animation during a transition,
+     including initial presentation.
+
+     Default value is 0.5.
+    */
+    var transitionDuration: Double { get }
+
+    /**
+     The animation options used when performing animations on the PanModal, utilized mostly
+     during a transition.
+
+     Default value is [.curveEaseInOut, .allowUserInteraction, .beginFromCurrentState].
+    */
+    var transitionAnimationOptions: UIView.AnimationOptions { get }
+
+    /**
+     The background view color.
 
      - Note: This is only utilized at the very start of the transition.
 
-     Default Value is 0.7.
-     */
-    var backgroundAlpha: CGFloat { get }
+     Default Value is black with alpha component 0.7.
+    */
+    var panModalBackgroundColor: UIColor { get }
+
+    /**
+     The drag indicator view color.
+
+     Default value is light gray.
+    */
+    var dragIndicatorBackgroundColor: UIColor { get }
 
     /**
      We configure the panScrollable's scrollIndicatorInsets interally so override this value
@@ -111,6 +135,13 @@ public protocol PanModalPresentable {
      */
     var allowsDragToDismiss: Bool { get }
 
+    /**
+     A flag to determine if dismissal should be initiated when tapping on the dimmed background view.
+
+     Default value is true.
+     */
+    var allowsTapToDismiss: Bool { get }
+
     /**
      A flag to toggle user interactions on the container view.
 
@@ -196,4 +227,11 @@ public protocol PanModalPresentable {
      */
     func panModalWillDismiss()
 
+    /**
+     Notifies the delegate after the pan modal is dismissed.
+
+     Default value is an empty implementation.
+     */
+    func panModalDidDismiss()
 }
+#endif

PanModal/Presenter/PanModalPresenter.swift

@@ -5,6 +5,7 @@
 //  Copyright © 2019 Tiny Speck, Inc. All rights reserved.
 //
 
+#if os(iOS)
 import UIKit
 
 /**
@@ -17,7 +18,7 @@ import UIKit
                                              sourceRect: .zero)
  ```
  */
-public protocol PanModalPresenter {
+protocol PanModalPresenter: AnyObject {
 
     /**
      A flag that returns true if the current presented view controller
@@ -28,6 +29,10 @@ public protocol PanModalPresenter {
     /**
      Presents a view controller that conforms to the PanModalPresentable protocol
      */
-    func presentPanModal(_ viewControllerToPresent: PanModalPresentable.LayoutType, sourceView: UIView?, sourceRect: CGRect)
+    func presentPanModal(_ viewControllerToPresent: PanModalPresentable.LayoutType,
+                         sourceView: UIView?,
+                         sourceRect: CGRect,
+                         completion: (() -> Void)?)
 
 }
+#endif

PanModal/Presenter/UIViewController+PanModalPresenter.swift

@@ -5,6 +5,7 @@
 //  Copyright © 2019 Tiny Speck, Inc. All rights reserved.
 //
 
+#if os(iOS)
 import UIKit
 
 /**
@@ -34,10 +35,14 @@ extension UIViewController: PanModalPresenter {
         - viewControllerToPresent: The view controller to be presented
         - sourceView: The view containing the anchor rectangle for the popover.
         - sourceRect: The rectangle in the specified view in which to anchor the popover.
+        - completion: The block to execute after the presentation finishes. You may specify nil for this parameter.
 
      - Note: sourceView & sourceRect are only required for presentation on an iPad.
      */
-    public func presentPanModal(_ viewControllerToPresent: PanModalPresentable.LayoutType, sourceView: UIView? = nil, sourceRect: CGRect = .zero) {
+    public func presentPanModal(_ viewControllerToPresent: PanModalPresentable.LayoutType,
+                                sourceView: UIView? = nil,
+                                sourceRect: CGRect = .zero,
+                                completion: (() -> Void)? = nil) {
 
         /**
          Here, we deliberately do not check for size classes. More info in `PanModalPresentationDelegate`
@@ -54,7 +59,8 @@ extension UIViewController: PanModalPresenter {
             viewControllerToPresent.transitioningDelegate = PanModalPresentationDelegate.default
         }
 
-        present(viewControllerToPresent, animated: true, completion: nil)
+        present(viewControllerToPresent, animated: true, completion: completion)
     }
 
 }
+#endif

PanModal/View/DimmedView.swift

@@ -5,6 +5,7 @@
 //  Copyright © 2017 Tiny Speck, Inc. All rights reserved.
 //
 
+#if os(iOS)
 import UIKit
 
 /**
@@ -31,12 +32,11 @@ public class DimmedView: UIView {
         didSet {
             switch dimState {
             case .max:
-                alpha = dimAlpha
+                alpha = 1.0
             case .off:
                 alpha = 0.0
             case .percent(let percentage):
-                let val = max(0.0, min(1.0, percentage))
-                alpha = dimAlpha * val
+                alpha = max(0.0, min(1.0, percentage))
             }
         }
     }
@@ -53,15 +53,12 @@ public class DimmedView: UIView {
         return UITapGestureRecognizer(target: self, action: #selector(didTapView))
     }()
 
-    private let dimAlpha: CGFloat
-
     // MARK: - Initializers
 
-    init(dimAlpha: CGFloat = 0.7) {
-        self.dimAlpha = dimAlpha
+    init(dimColor: UIColor = UIColor.black.withAlphaComponent(0.7)) {
         super.init(frame: .zero)
         alpha = 0.0
-        backgroundColor = .black
+        backgroundColor = dimColor
         addGestureRecognizer(tapGesture)
     }
 
@@ -76,3 +73,4 @@ public class DimmedView: UIView {
     }
 
 }
+#endif

PanModal/View/PanContainerView.swift

@@ -5,6 +5,7 @@
 //  Copyright © 2018 Tiny Speck, Inc. All rights reserved.
 //
 
+#if os(iOS)
 import UIKit
 
 /**
@@ -20,8 +21,9 @@ class PanContainerView: UIView {
         addSubview(presentedView)
     }
 
+    @available(*, unavailable)
     required init?(coder aDecoder: NSCoder) {
-        fatalError()
+        fatalError("init(coder:) has not been implemented")
     }
 
 }
@@ -33,7 +35,10 @@ extension UIView {
      from the view hierachy
      */
     var panContainerView: PanContainerView? {
-        return subviews.compactMap({ $0 as? PanContainerView }).first
+        return subviews.first(where: { view -> Bool in
+            view is PanContainerView
+        }) as? PanContainerView
     }
 
 }
+#endif

PanModalDemo.xcodeproj/project.pbxproj

@@ -41,6 +41,7 @@
 		943904ED2226366700859537 /* AlertViewController.swift in Sources */ = {isa = PBXBuildFile; fileRef = 943904EC2226366700859537 /* AlertViewController.swift */; };
 		943904EF2226383700859537 /* NavigationController.swift in Sources */ = {isa = PBXBuildFile; fileRef = 943904EE2226383700859537 /* NavigationController.swift */; };
 		943904F32226484F00859537 /* UserGroupStackedViewController.swift in Sources */ = {isa = PBXBuildFile; fileRef = 943904F22226484F00859537 /* UserGroupStackedViewController.swift */; };
+		944EBA2E227BB7F400C4C97B /* FullScreenNavController.swift in Sources */ = {isa = PBXBuildFile; fileRef = 944EBA2D227BB7F400C4C97B /* FullScreenNavController.swift */; };
 		94795C9B21F0335D008045A0 /* PanModalPresentationDelegate.swift in Sources */ = {isa = PBXBuildFile; fileRef = 94795C9A21F0335D008045A0 /* PanModalPresentationDelegate.swift */; };
 		94795C9D21F03368008045A0 /* PanContainerView.swift in Sources */ = {isa = PBXBuildFile; fileRef = 94795C9C21F03368008045A0 /* PanContainerView.swift */; };
 		DC13905E216D90D5007A3E64 /* Assets.xcassets in Resources */ = {isa = PBXBuildFile; fileRef = DC13905D216D90D5007A3E64 /* Assets.xcassets */; };
@@ -112,6 +113,7 @@
 		943904EC2226366700859537 /* AlertViewController.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = AlertViewController.swift; sourceTree = "<group>"; };
 		943904EE2226383700859537 /* NavigationController.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = NavigationController.swift; sourceTree = "<group>"; };
 		943904F22226484F00859537 /* UserGroupStackedViewController.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = UserGroupStackedViewController.swift; sourceTree = "<group>"; };
+		944EBA2D227BB7F400C4C97B /* FullScreenNavController.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = FullScreenNavController.swift; sourceTree = "<group>"; };
 		94795C9A21F0335D008045A0 /* PanModalPresentationDelegate.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = PanModalPresentationDelegate.swift; sourceTree = "<group>"; };
 		94795C9C21F03368008045A0 /* PanContainerView.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = PanContainerView.swift; sourceTree = "<group>"; };
 		DC13905D216D90D5007A3E64 /* Assets.xcassets */ = {isa = PBXFileReference; lastKnownFileType = folder.assetcatalog; path = Assets.xcassets; sourceTree = "<group>"; };
@@ -238,6 +240,22 @@
 			path = Presenter;
 			sourceTree = "<group>";
 		};
+		944EBA2B227BB7D900C4C97B /* Basic */ = {
+			isa = PBXGroup;
+			children = (
+				943904EA2226354100859537 /* BasicViewController.swift */,
+			);
+			path = Basic;
+			sourceTree = "<group>";
+		};
+		944EBA2C227BB7E100C4C97B /* Full Screen */ = {
+			isa = PBXGroup;
+			children = (
+				944EBA2D227BB7F400C4C97B /* FullScreenNavController.swift */,
+			);
+			path = "Full Screen";
+			sourceTree = "<group>";
+		};
 		DC13905F216D93AB007A3E64 /* Resources */ = {
 			isa = PBXGroup;
 			children = (
@@ -310,7 +328,8 @@
 		DC139079216D9AAA007A3E64 /* View Controllers */ = {
 			isa = PBXGroup;
 			children = (
-				943904EA2226354100859537 /* BasicViewController.swift */,
+				944EBA2B227BB7D900C4C97B /* Basic */,
+				944EBA2C227BB7E100C4C97B /* Full Screen */,
 				DC3B2EBB222A5882000C8A4A /* Alert */,
 				DC3B2EBC222A5893000C8A4A /* Alert (Transient) */,
 				743CB2AB222661EA00665A55 /* User Groups (Stacked) */,
@@ -567,6 +586,7 @@
 				DC139075216D9458007A3E64 /* DimmedView.swift in Sources */,
 				743CABD322265F2E00634A5A /* ProfileViewController.swift in Sources */,
 				DC139070216D9458007A3E64 /* PanModalPresentationAnimator.swift in Sources */,
+				944EBA2E227BB7F400C4C97B /* FullScreenNavController.swift in Sources */,
 				DCA741AE216D90410021F2F2 /* AppDelegate.swift in Sources */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;
@@ -609,7 +629,7 @@
 				PRODUCT_BUNDLE_IDENTIFIER = com.slack.PanModal;
 				PRODUCT_NAME = "$(TARGET_NAME:c99extidentifier)";
 				SKIP_INSTALL = YES;
-				SWIFT_VERSION = 4.2;
+				SWIFT_VERSION = 5.0;
 				TARGETED_DEVICE_FAMILY = "1,2";
 				VERSIONING_SYSTEM = "apple-generic";
 				VERSION_INFO_PREFIX = "";
@@ -638,7 +658,7 @@
 				PRODUCT_BUNDLE_IDENTIFIER = com.slack.PanModal;
 				PRODUCT_NAME = "$(TARGET_NAME:c99extidentifier)";
 				SKIP_INSTALL = YES;
-				SWIFT_VERSION = 4.2;
+				SWIFT_VERSION = 5.0;
 				TARGETED_DEVICE_FAMILY = "1,2";
 				VERSIONING_SYSTEM = "apple-generic";
 				VERSION_INFO_PREFIX = "";
@@ -659,7 +679,7 @@
 				);
 				PRODUCT_BUNDLE_IDENTIFIER = slack.PanModalTests;
 				PRODUCT_NAME = "$(TARGET_NAME)";
-				SWIFT_VERSION = 4.2;
+				SWIFT_VERSION = 5.0;
 				TARGETED_DEVICE_FAMILY = "1,2";
 				TEST_HOST = "$(BUILT_PRODUCTS_DIR)/PanModalDemo.app/PanModalDemo";
 			};
@@ -679,7 +699,7 @@
 				);
 				PRODUCT_BUNDLE_IDENTIFIER = slack.PanModalTests;
 				PRODUCT_NAME = "$(TARGET_NAME)";
-				SWIFT_VERSION = 4.2;
+				SWIFT_VERSION = 5.0;
 				TARGETED_DEVICE_FAMILY = "1,2";
 				TEST_HOST = "$(BUILT_PRODUCTS_DIR)/PanModalDemo.app/PanModalDemo";
 			};
@@ -743,6 +763,7 @@
 				SDKROOT = iphoneos;
 				SWIFT_ACTIVE_COMPILATION_CONDITIONS = DEBUG;
 				SWIFT_OPTIMIZATION_LEVEL = "-Onone";
+				SWIFT_VERSION = 5.0;
 			};
 			name = Debug;
 		};
@@ -797,6 +818,7 @@
 				SDKROOT = iphoneos;
 				SWIFT_COMPILATION_MODE = wholemodule;
 				SWIFT_OPTIMIZATION_LEVEL = "-O";
+				SWIFT_VERSION = 5.0;
 				VALIDATE_PRODUCT = YES;
 			};
 			name = Release;
@@ -817,7 +839,7 @@
 				);
 				PRODUCT_BUNDLE_IDENTIFIER = com.PanModal;
 				PRODUCT_NAME = "$(TARGET_NAME)";
-				SWIFT_VERSION = 4.2;
+				SWIFT_VERSION = 5.0;
 				TARGETED_DEVICE_FAMILY = "1,2";
 			};
 			name = Debug;
@@ -838,7 +860,7 @@
 				);
 				PRODUCT_BUNDLE_IDENTIFIER = com.PanModal;
 				PRODUCT_NAME = "$(TARGET_NAME)";
-				SWIFT_VERSION = 4.2;
+				SWIFT_VERSION = 5.0;
 				TARGETED_DEVICE_FAMILY = "1,2";
 			};
 			name = Release;

README.md

@@ -1,10 +1,13 @@
+
+### PanModal is an elegant and highly customizable presentation API for constructing bottom sheet modals on iOS.
+
 <p align="center">
     <img src="https://github.com/slackhq/PanModal/raw/master/Screenshots/panModal.gif" width="30%" height="30%" alt="Screenshot Preview" />
 </p>
 
 <p align="center">
     <img src="https://img.shields.io/badge/Platform-iOS_10+-green.svg" alt="Platform: iOS 10.0+" />
-    <a href="https://developer.apple.com/swift" target="_blank"><img src="https://img.shields.io/badge/Language-Swift_4-blueviolet.svg" alt="Language: Swift 4" /></a>
+    <a href="https://developer.apple.com/swift" target="_blank"><img src="https://img.shields.io/badge/Language-Swift_5-blueviolet.svg" alt="Language: Swift 5" /></a>
     <a href="https://cocoapods.org/pods/PanModal" target="_blank"><img src="https://img.shields.io/badge/CocoaPods-v1.0-red.svg" alt="CocoaPods compatible" /></a>
     <a href="https://github.com/Carthage/Carthage" target="_blank"><img src="https://img.shields.io/badge/Carthage-compatible-blue.svg" alt="Carthage compatible" /></a>
     <img src="https://img.shields.io/badge/License-MIT-green.svg" alt="License: MIT" />
@@ -21,6 +24,12 @@
   • <a href="#license">License</a>
 </p>
 
+<p align="center">
+Read our <a href="https://slack.engineering/panmodal-better-support-for-thumb-accessibility-on-slack-mobile-52b2a7596031" target="_blank">blog</a> on how Slack is getting more :thumbsup: with PanModal
+
+Swift 4.2 support can be found on the `Swift4.2` branch.
+</p>
+
 ## Features
 
 * Supports any type of `UIViewController`
@@ -45,6 +54,14 @@ pod 'PanModal'
 github "slackhq/PanModal"
 ```
 
+* <a href="https://swift.org/package-manager/" target="_blank">Swift Package Manager</a>:
+
+```swift
+dependencies: [
+  .package(url: "https://github.com/slackhq/PanModal.git", .exact("1.2.6")),
+],
+```
+
 ## Usage
 
 PanModal was designed to be used effortlessly. Simply call `presentPanModal` in the same way you would expect to present a `UIViewController`
@@ -130,7 +147,7 @@ We will only be fixing critical bugs, thus, for any non-critical issues or featu
 
 ## Authors
 
-[Stephen Sowole](https://github.com/tun57) • [Tosin Afolabi](https://github.com/tosinaf)
+[Stephen Sowole](https://github.com/ste57) • [Tosin Afolabi](https://github.com/tosinaf)
 
 ## License
 

Sample/SampleViewController.swift

@@ -67,6 +67,7 @@ private extension SampleViewController {
 
     enum RowType: Int, CaseIterable {
         case basic
+        case fullScreen
         case alert
         case transientAlert
         case userGroups
@@ -77,6 +78,7 @@ private extension SampleViewController {
         var presentable: RowPresentable {
             switch self {
             case .basic: return Basic()
+            case .fullScreen: return FullScreen()
             case .alert: return Alert()
             case .transientAlert: return TransientAlert()
             case .userGroups: return UserGroup()
@@ -86,33 +88,38 @@ private extension SampleViewController {
         }
 
         struct Basic: RowPresentable {
-            var string: String { return "Basic" }
-            var rowVC: PanModalPresentable.LayoutType { return BasicViewController() }
+            let string: String = "Basic"
+            let rowVC: PanModalPresentable.LayoutType = BasicViewController()
+        }
+
+        struct FullScreen: RowPresentable {
+            let string: String = "Full Screen"
+            let rowVC: PanModalPresentable.LayoutType = FullScreenNavController()
         }
 
         struct Alert: RowPresentable {
-            var string: String { return "Alert" }
-            var rowVC: PanModalPresentable.LayoutType { return AlertViewController() }
+            let string: String = "Alert"
+            let rowVC: PanModalPresentable.LayoutType = AlertViewController()
         }
 
         struct TransientAlert: RowPresentable {
-            var string: String { return "Alert (Transient)"}
-            var rowVC: PanModalPresentable.LayoutType { return TransientAlertViewController() }
+            let string: String = "Alert (Transient)"
+            let rowVC: PanModalPresentable.LayoutType = TransientAlertViewController()
         }
 
         struct UserGroup: RowPresentable {
-            var string: String { return "User Groups" }
-            var rowVC: PanModalPresentable.LayoutType { return UserGroupViewController() }
+            let string: String = "User Groups"
+            let rowVC: PanModalPresentable.LayoutType = UserGroupViewController()
         }
 
         struct Navigation: RowPresentable {
-            var string: String { return "User Groups (NavigationController)" }
-            var rowVC: PanModalPresentable.LayoutType { return NavigationController() }
+            let string: String = "User Groups (NavigationController)"
+            let rowVC: PanModalPresentable.LayoutType = NavigationController()
         }
 
         struct Stacked: RowPresentable {
-            var string: String { return "User Groups (Stacked)" }
-            var rowVC: PanModalPresentable.LayoutType { return UserGroupStackedViewController() }
+            let string: String = "User Groups (Stacked)"
+            let rowVC: PanModalPresentable.LayoutType = UserGroupStackedViewController()
         }
     }
 }

Sample/View Controllers/Alert (Transient)/TransientAlertViewController.swift

@@ -59,8 +59,8 @@ class TransientAlertViewController: AlertViewController {
         return true
     }
 
-    override var backgroundAlpha: CGFloat {
-        return 0.0
+    override var panModalBackgroundColor: UIColor {
+        return .clear
     }
 
     override var isUserInteractionEnabled: Bool {

Sample/View Controllers/Alert/AlertViewController.swift

@@ -46,8 +46,8 @@ class AlertViewController: UIViewController, PanModalPresentable {
         return shortFormHeight
     }
 
-    var backgroundAlpha: CGFloat {
-        return 0.1
+    var panModalBackgroundColor: UIColor {
+        return UIColor.black.withAlphaComponent(0.1)
     }
 
     var shouldRoundTopCorners: Bool {

Sample/View Controllers/Full Screen/FullScreenNavController.swift

@@ -0,0 +1,73 @@
+//
+//  FullScreenNavController.swift
+//  PanModalDemo
+//
+//  Created by Stephen Sowole on 5/2/19.
+//  Copyright © 2019 Detail. All rights reserved.
+//
+
+import UIKit
+
+class FullScreenNavController: UINavigationController {
+
+    override func viewDidLoad() {
+        super.viewDidLoad()
+        pushViewController(FullScreenViewController(), animated: false)
+    }
+}
+
+extension FullScreenNavController: PanModalPresentable {
+
+    var panScrollable: UIScrollView? {
+        return nil
+    }
+
+    var topOffset: CGFloat {
+        return 0.0
+    }
+
+    var springDamping: CGFloat {
+        return 1.0
+    }
+
+    var transitionDuration: Double {
+        return 0.4
+    }
+
+    var transitionAnimationOptions: UIView.AnimationOptions {
+        return [.allowUserInteraction, .beginFromCurrentState]
+    }
+
+    var shouldRoundTopCorners: Bool {
+        return false
+    }
+
+    var showDragIndicator: Bool {
+        return false
+    }
+}
+
+private class FullScreenViewController: UIViewController {
+
+    let textLabel: UILabel = {
+        let label = UILabel()
+        label.text = "Drag downwards to dismiss"
+        label.font = UIFont(name: "Lato-Bold", size: 17)
+        label.translatesAutoresizingMaskIntoConstraints = false
+        return label
+    }()
+
+    override func viewDidLoad() {
+        super.viewDidLoad()
+        title = "Full Screen"
+        view.backgroundColor = .white
+        setupConstraints()
+    }
+
+    private func setupConstraints() {
+        view.addSubview(textLabel)
+        textLabel.centerXAnchor.constraint(equalTo: view.centerXAnchor).isActive = true
+        textLabel.centerYAnchor.constraint(equalTo: view.centerYAnchor).isActive = true
+    }
+
+}

Sample/View Controllers/User Groups (Navigation Controller)/NavigationController.swift

@@ -12,13 +12,17 @@ class NavigationController: UINavigationController, PanModalPresentable {
 
     private let navGroups = NavUserGroups()
 
-    override var preferredStatusBarStyle: UIStatusBarStyle {
-        return .lightContent
+    init() {
+        super.init(nibName: nil, bundle: nil)
+        viewControllers = [navGroups]
     }
 
-    override func viewDidLoad() {
-        super.viewDidLoad()
-        pushViewController(navGroups, animated: false)
+    required init?(coder aDecoder: NSCoder) {
+        fatalError()
+    }
+
+    override var preferredStatusBarStyle: UIStatusBarStyle {
+        return .lightContent
     }
 
     override func popViewController(animated: Bool) -> UIViewController? {

Sample/View Controllers/User Groups/UserGroupViewController.swift

@@ -8,7 +8,7 @@
 
 import UIKit
 
-class UserGroupViewController: UITableViewController, PanModalPresentable, UIGestureRecognizerDelegate {
+class UserGroupViewController: UITableViewController, PanModalPresentable {
 
     let members: [UserGroupMemberPresentable] = [
         UserGroupMemberPresentable(name: "Naida Schill ✈️", role: "Staff Engineer - Mobile DevXP", avatarBackgroundColor: #colorLiteral(red: 0.7215686275, green: 0.9098039216, blue: 0.5607843137, alpha: 1)),

Tests/PanModalTests.swift

@@ -48,17 +48,21 @@ class PanModalTests: XCTestCase {
         XCTAssertEqual(vc.shortFormHeight, PanModalHeight.maxHeight)
         XCTAssertEqual(vc.longFormHeight, PanModalHeight.maxHeight)
         XCTAssertEqual(vc.springDamping, 0.8)
-        XCTAssertEqual(vc.backgroundAlpha, 0.7)
+        XCTAssertEqual(vc.panModalBackgroundColor, UIColor.black.withAlphaComponent(0.7))
+        XCTAssertEqual(vc.dragIndicatorBackgroundColor, UIColor.lightGray)
         XCTAssertEqual(vc.scrollIndicatorInsets, .zero)
         XCTAssertEqual(vc.anchorModalToLongForm, true)
         XCTAssertEqual(vc.allowsExtendedPanScrolling, false)
         XCTAssertEqual(vc.allowsDragToDismiss, true)
+        XCTAssertEqual(vc.allowsTapToDismiss, true)
         XCTAssertEqual(vc.isUserInteractionEnabled, true)
         XCTAssertEqual(vc.isHapticFeedbackEnabled, true)
         XCTAssertEqual(vc.shouldRoundTopCorners, false)
         XCTAssertEqual(vc.showDragIndicator, false)
         XCTAssertEqual(vc.shouldRoundTopCorners, false)
         XCTAssertEqual(vc.cornerRadius, 8.0)
+        XCTAssertEqual(vc.transitionDuration, PanModalAnimator.Constants.defaultTransitionDuration)
+        XCTAssertEqual(vc.transitionAnimationOptions, [.curveEaseInOut, .allowUserInteraction, .beginFromCurrentState])
     }
 
     func testPresentableYValues() {