Can anyone tell me how I can mimic the bottom sheet in the new Apple Maps app in iOS 10?
In Android, you can use a BottomSheet which mimics this behaviour, but I could not find anything like that for iOS.
Is that a simple scroll view with a content inset, so that the search bar is at the bottom?
I am fairly new to iOS programming so if someone could help me creating this layout, that would be highly appreciated.
This is what I mean by "bottom sheet":
I don't know how exactly the bottom sheet of the new Maps app, responds to user interactions. But you can create a custom view that looks like the one in the screenshots and add it to the main view.
I assume you know how to:
1- create view controllers either by storyboards or using xib files.
2- use googleMaps or Apple's MapKit.
Example
1- Create 2 view controllers e.g, MapViewController and BottomSheetViewController. The first controller will host the map and the second is the bottom sheet itself.
Configure MapViewController
Create a method to add the bottom sheet view.
func addBottomSheetView() {
// 1- Init bottomSheetVC
let bottomSheetVC = BottomSheetViewController()
// 2- Add bottomSheetVC as a child view
self.addChildViewController(bottomSheetVC)
self.view.addSubview(bottomSheetVC.view)
bottomSheetVC.didMoveToParentViewController(self)
// 3- Adjust bottomSheet frame and initial position.
let height = view.frame.height
let width = view.frame.width
bottomSheetVC.view.frame = CGRectMake(0, self.view.frame.maxY, width, height)
}
And call it in viewDidAppear method:
override func viewDidAppear(animated: Bool) {
super.viewDidAppear(animated)
addBottomSheetView()
}
Configure BottomSheetViewController
1) Prepare background
Create a method to add blur and vibrancy effects
func prepareBackgroundView(){
let blurEffect = UIBlurEffect.init(style: .Dark)
let visualEffect = UIVisualEffectView.init(effect: blurEffect)
let bluredView = UIVisualEffectView.init(effect: blurEffect)
bluredView.contentView.addSubview(visualEffect)
visualEffect.frame = UIScreen.mainScreen().bounds
bluredView.frame = UIScreen.mainScreen().bounds
view.insertSubview(bluredView, atIndex: 0)
}
call this method in your viewWillAppear
override func viewWillAppear(animated: Bool) {
super.viewWillAppear(animated)
prepareBackgroundView()
}
Make sure that your controller's view background color is clearColor.
2) Animate bottomSheet appearance
override func viewDidAppear(animated: Bool) {
super.viewDidAppear(animated)
UIView.animateWithDuration(0.3) { [weak self] in
let frame = self?.view.frame
let yComponent = UIScreen.mainScreen().bounds.height - 200
self?.view.frame = CGRectMake(0, yComponent, frame!.width, frame!.height)
}
}
3) Modify your xib as you want.
4) Add Pan Gesture Recognizer to your view.
In your viewDidLoad method add UIPanGestureRecognizer.
override func viewDidLoad() {
super.viewDidLoad()
let gesture = UIPanGestureRecognizer.init(target: self, action: #selector(BottomSheetViewController.panGesture))
view.addGestureRecognizer(gesture)
}
And implement your gesture behaviour:
func panGesture(recognizer: UIPanGestureRecognizer) {
let translation = recognizer.translationInView(self.view)
let y = self.view.frame.minY
self.view.frame = CGRectMake(0, y + translation.y, view.frame.width, view.frame.height)
recognizer.setTranslation(CGPointZero, inView: self.view)
}
Scrollable Bottom Sheet:
If your custom view is a scroll view or any other view that inherits from, so you have two options:
First:
Design the view with a header view and add the panGesture to the header. (bad user experience).
Second:
1 - Add the panGesture to the bottom sheet view.
2 - Implement the UIGestureRecognizerDelegate and set the panGesture delegate to the controller.
3- Implement shouldRecognizeSimultaneouslyWith delegate function and disable the scrollView isScrollEnabled property in two case:
The view is partially visible.
The view is totally visible, the scrollView contentOffset property is 0 and the user is dragging the view downwards.
Otherwise enable scrolling.
func gestureRecognizer(_ gestureRecognizer: UIGestureRecognizer, shouldRecognizeSimultaneouslyWith otherGestureRecognizer: UIGestureRecognizer) -> Bool {
let gesture = (gestureRecognizer as! UIPanGestureRecognizer)
let direction = gesture.velocity(in: view).y
let y = view.frame.minY
if (y == fullView && tableView.contentOffset.y == 0 && direction > 0) || (y == partialView) {
tableView.isScrollEnabled = false
} else {
tableView.isScrollEnabled = true
}
return false
}
NOTE
In case you set .allowUserInteraction as an animation option, like in the sample project, so you need to enable scrolling on the animation completion closure if the user is scrolling up.
Sample Project
I created a sample project with more options on this repo which may give you better insights about how to customise the flow.
In the demo, addBottomSheetView() function controls which view should be used as a bottom sheet.
Sample Project Screenshots
- Partial View
- FullView
- Scrollable View
Update iOS 15
In iOS 15, you can now use the native UISheetPresentationController.
if let sheet = viewControllerToPresent.sheetPresentationController {
sheet.detents = [.medium(), .large()]
// your sheet setup
}
present(viewControllerToPresent, animated: true, completion: nil)
Notice that you can even reproduce its navigation stack using the overcurrentcontext presentation mode:
let nextViewControllerToPresent: UIViewController = ...
nextViewControllerToPresent.modalPresentationStyle = .overCurrentContext
viewControllerToPresent.present(nextViewControllerToPresent, animated: true, completion: nil)
Legacy
I released a library based on my answer below.
It mimics the Shortcuts application overlay. See this article for details.
The main component of the library is the OverlayContainerViewController. It defines an area where a view controller can be dragged up and down, hiding or revealing the content underneath it.
let contentController = MapsViewController()
let overlayController = SearchViewController()
let containerController = OverlayContainerViewController()
containerController.delegate = self
containerController.viewControllers = [
contentController,
overlayController
]
window?.rootViewController = containerController
Implement OverlayContainerViewControllerDelegate to specify the number of notches wished:
enum OverlayNotch: Int, CaseIterable {
case minimum, medium, maximum
}
func numberOfNotches(in containerViewController: OverlayContainerViewController) -> Int {
return OverlayNotch.allCases.count
}
func overlayContainerViewController(_ containerViewController: OverlayContainerViewController,
heightForNotchAt index: Int,
availableSpace: CGFloat) -> CGFloat {
switch OverlayNotch.allCases[index] {
case .maximum:
return availableSpace * 3 / 4
case .medium:
return availableSpace / 2
case .minimum:
return availableSpace * 1 / 4
}
}
SwiftUI (12/29/20)
A SwiftUI version of the library is now available.
Color.red.dynamicOverlay(Color.green)
Previous answer
I think there is a significant point that is not treated in the suggested solutions: the transition between the scroll and the translation.
In Maps, as you may have noticed, when the tableView reaches contentOffset.y == 0, the bottom sheet either slides up or goes down.
The point is tricky because we can not simply enable/disable the scroll when our pan gesture begins the translation. It would stop the scroll until a new touch begins. This is the case in most of the proposed solutions here.
Here is my try to implement this motion.
Starting point: Maps App
To start our investigation, let's visualize the view hierarchy of Maps (start Maps on a simulator and select Debug > Attach to process by PID or Name > Maps in Xcode 9).
It doesn't tell how the motion works, but it helped me to understand the logic of it. You can play with the lldb and the view hierarchy debugger.
Our view controller stacks
Let's create a basic version of the Maps ViewController architecture.
We start with a BackgroundViewController (our map view):
class BackgroundViewController: UIViewController {
override func loadView() {
view = MKMapView()
}
}
We put the tableView in a dedicated UIViewController:
class OverlayViewController: UIViewController, UITableViewDataSource, UITableViewDelegate {
lazy var tableView = UITableView()
override func loadView() {
view = tableView
tableView.dataSource = self
tableView.delegate = self
}
[...]
}
Now, we need a VC to embed the overlay and manage its translation.
To simplify the problem, we consider that it can translate the overlay from one static point OverlayPosition.maximum to another OverlayPosition.minimum.
For now it only has one public method to animate the position change and it has a transparent view:
enum OverlayPosition {
case maximum, minimum
}
class OverlayContainerViewController: UIViewController {
let overlayViewController: OverlayViewController
var translatedViewHeightContraint = ...
override func loadView() {
view = UIView()
}
func moveOverlay(to position: OverlayPosition) {
[...]
}
}
Finally we need a ViewController to embed the all:
class StackViewController: UIViewController {
private var viewControllers: [UIViewController]
override func viewDidLoad() {
super.viewDidLoad()
viewControllers.forEach { gz_addChild($0, in: view) }
}
}
In our AppDelegate, our startup sequence looks like:
let overlay = OverlayViewController()
let containerViewController = OverlayContainerViewController(overlayViewController: overlay)
let backgroundViewController = BackgroundViewController()
window?.rootViewController = StackViewController(viewControllers: [backgroundViewController, containerViewController])
The difficulty behind the overlay translation
Now, how to translate our overlay?
Most of the proposed solutions use a dedicated pan gesture recognizer, but we actually already have one : the pan gesture of the table view.
Moreover, we need to keep the scroll and the translation synchronised and the UIScrollViewDelegate has all the events we need!
A naive implementation would use a second pan Gesture and try to reset the contentOffset of the table view when the translation occurs:
func panGestureAction(_ recognizer: UIPanGestureRecognizer) {
if isTranslating {
tableView.contentOffset = .zero
}
}
But it does not work. The tableView updates its contentOffset when its own pan gesture recognizer action triggers or when its displayLink callback is called. There is no chance that our recognizer triggers right after those to successfully override the contentOffset.
Our only chance is either to take part of the layout phase (by overriding layoutSubviews of the scroll view calls at each frame of the scroll view) or to respond to the didScroll method of the delegate called each time the contentOffset is modified. Let's try this one.
The translation Implementation
We add a delegate to our OverlayVC to dispatch the scrollview's events to our translation handler, the OverlayContainerViewController :
protocol OverlayViewControllerDelegate: class {
func scrollViewDidScroll(_ scrollView: UIScrollView)
func scrollViewDidStopScrolling(_ scrollView: UIScrollView)
}
class OverlayViewController: UIViewController {
[...]
func scrollViewDidScroll(_ scrollView: UIScrollView) {
delegate?.scrollViewDidScroll(scrollView)
}
func scrollViewDidEndDragging(_ scrollView: UIScrollView, willDecelerate decelerate: Bool) {
delegate?.scrollViewDidStopScrolling(scrollView)
}
}
In our container, we keep track of the translation using a enum:
enum OverlayInFlightPosition {
case minimum
case maximum
case progressing
}
The current position calculation looks like :
private var overlayInFlightPosition: OverlayInFlightPosition {
let height = translatedViewHeightContraint.constant
if height == maximumHeight {
return .maximum
} else if height == minimumHeight {
return .minimum
} else {
return .progressing
}
}
We need 3 methods to handle the translation:
The first one tells us if we need to start the translation.
private func shouldTranslateView(following scrollView: UIScrollView) -> Bool {
guard scrollView.isTracking else { return false }
let offset = scrollView.contentOffset.y
switch overlayInFlightPosition {
case .maximum:
return offset < 0
case .minimum:
return offset > 0
case .progressing:
return true
}
}
The second one performs the translation. It uses the translation(in:) method of the scrollView's pan gesture.
private func translateView(following scrollView: UIScrollView) {
scrollView.contentOffset = .zero
let translation = translatedViewTargetHeight - scrollView.panGestureRecognizer.translation(in: view).y
translatedViewHeightContraint.constant = max(
Constant.minimumHeight,
min(translation, Constant.maximumHeight)
)
}
The third one animates the end of the translation when the user releases its finger. We calculate the position using the velocity & the current position of the view.
private func animateTranslationEnd() {
let position: OverlayPosition = // ... calculation based on the current overlay position & velocity
moveOverlay(to: position)
}
Our overlay's delegate implementation simply looks like :
class OverlayContainerViewController: UIViewController {
func scrollViewDidScroll(_ scrollView: UIScrollView) {
guard shouldTranslateView(following: scrollView) else { return }
translateView(following: scrollView)
}
func scrollViewDidStopScrolling(_ scrollView: UIScrollView) {
// prevent scroll animation when the translation animation ends
scrollView.isEnabled = false
scrollView.isEnabled = true
animateTranslationEnd()
}
}
Final problem: dispatching the overlay container's touches
The translation is now pretty efficient. But there is still a final problem: the touches are not delivered to our background view. They are all intercepted by the overlay container's view.
We can not set isUserInteractionEnabled to false because it would also disable the interaction in our table view. The solution is the one used massively in the Maps app, PassThroughView:
class PassThroughView: UIView {
override func hitTest(_ point: CGPoint, with event: UIEvent?) -> UIView? {
let view = super.hitTest(point, with: event)
if view == self {
return nil
}
return view
}
}
It removes itself from the responder chain.
In OverlayContainerViewController:
override func loadView() {
view = PassThroughView()
}
Result
Here is the result:
You can find the code here.
Please if you see any bugs, let me know ! Note that your implementation can of course use a second pan gesture, specially if you add a header in your overlay.
Update 23/08/18
We can replace scrollViewDidEndDragging with
willEndScrollingWithVelocity rather than enabling/disabling the scroll when the user ends dragging:
func scrollView(_ scrollView: UIScrollView,
willEndScrollingWithVelocity velocity: CGPoint,
targetContentOffset: UnsafeMutablePointer<CGPoint>) {
switch overlayInFlightPosition {
case .maximum:
break
case .minimum, .progressing:
targetContentOffset.pointee = .zero
}
animateTranslationEnd(following: scrollView)
}
We can use a spring animation and allow user interaction while animating to make the motion flow better:
func moveOverlay(to position: OverlayPosition,
duration: TimeInterval,
velocity: CGPoint) {
overlayPosition = position
translatedViewHeightContraint.constant = translatedViewTargetHeight
UIView.animate(
withDuration: duration,
delay: 0,
usingSpringWithDamping: velocity.y == 0 ? 1 : 0.6,
initialSpringVelocity: abs(velocity.y),
options: [.allowUserInteraction],
animations: {
self.view.layoutIfNeeded()
}, completion: nil)
}
Try Pulley:
Pulley is an easy to use drawer library meant to imitate the drawer
in iOS 10's Maps app. It exposes a simple API that allows you to use
any UIViewController subclass as the drawer content or the primary
content.
https://github.com/52inc/Pulley
I wrote my own library to achieve the intended behaviour in ios Maps app. It is a protocol oriented solution. So you don't need to inherit any base class instead create a sheet controller and configure as you wish. It also supports inner navigation/presentation with or without UINavigationController.
See below link for more details.
https://github.com/OfTheWolf/UBottomSheet
You can try my answer https://github.com/SCENEE/FloatingPanel. It provides a container view controller to display a "bottom sheet" interface.
It's easy to use and you don't mind any gesture recognizer handling! Also you can track a scroll view's(or the sibling view) in a bottom sheet if needed.
This is a simple example. Please note that you need to prepare a view controller to display your content in a bottom sheet.
import UIKit
import FloatingPanel
class ViewController: UIViewController {
var fpc: FloatingPanelController!
override func viewDidLoad() {
super.viewDidLoad()
fpc = FloatingPanelController()
// Add "bottom sheet" in self.view.
fpc.add(toParent: self)
// Add a view controller to display your contents in "bottom sheet".
let contentVC = ContentViewController()
fpc.set(contentViewController: contentVC)
// Track a scroll view in "bottom sheet" content if needed.
fpc.track(scrollView: contentVC.tableView)
}
...
}
Here is another example code to display a bottom sheet to search a location like Apple Maps.
iOS 15 in 2021 adds UISheetPresentationController, which is Apple's first public release of an Apple Maps-style "bottom sheet":
UISheetPresentationController
UISheetPresentationController lets you present your view controller as a sheet. Before you present your view controller, configure its sheet presentation controller with the behavior and appearance you want for your sheet.
Sheet presentation controllers specify a sheet's size based on a detent, a height where a sheet naturally rests. Detents allow a sheet to resize from one edge of its fully expanded frame while the other three edges remain fixed. You specify the detents that a sheet supports using detents, and monitor its most recently selected detent using selectedDetentIdentifier.
https://developer.apple.com/documentation/uikit/uisheetpresentationcontroller
This new bottom sheet control is explored in WWDC Session 10063: Customize and Resize Sheets in UIKit
Unfortunately....
In iOS 15, the UISheetPresentationController has launched with only medium and large detents.
A small detent is notably absent from the iOS 15 API, which would be required to display an always-presented "collapsed" bottom sheet like Apple Maps:
Custom smaller Detents in UISheetPresentationController?
The medium detent was released to handle use cases such as the Share Sheet or the "••• More" menu in Mail: a button-triggered half sheet.
In iOS 15, Apple Maps is now using this UIKit sheet presentation rather than a custom implementation, which is a huge step in the right direction. Apple Maps in iOS 15 continues to show the "small" bar, as well as a 1/3rd height bar. But those view sizes are not public API available to developers.
UIKit engineers at the WWDC 2021 Labs seemed to know that a small detent would be a hugely popular UIKit component. I would expect to see an API expansion for iOS 16 next year.
We’ve just released a pure Swift Package supporting iOS 11.4+ which provides you a BottomSheet with theme and behavior options you can customize. This component is easy to use, and flexible. You can find it here: https://github.com/LunabeeStudio/LBBottomSheet.
A demo project is available in this repository too.
For example, it supports different ways to manage the needed height, and also adds to the controller behind it the ability to detect height changes and adapt its bottom content inset.
You can find more information on the GitHub repository and in the documentation: https://lbbottomsheet.lunabee.studio.
I think it can help you to do what you’re looking for. Don’t hesitate to tell me if you have comments/questions :)
Here you can see one of all the possible BottomSheet configurations:
**for iOS 15 Native Support available for this **
#IBAction func openSheet() {
let secondVC = self.storyboard?.instantiateViewController(withIdentifier: "SecondViewController")
// Create the view controller.
if #available(iOS 15.0, *) {
let formNC = UINavigationController(rootViewController: secondVC!)
formNC.modalPresentationStyle = UIModalPresentationStyle.pageSheet
guard let sheetPresentationController = formNC.presentationController as? UISheetPresentationController else {
return
}
sheetPresentationController.detents = [.medium(), .large()]
sheetPresentationController.prefersGrabberVisible = true
present(formNC, animated: true, completion: nil)
} else {
// Fallback on earlier versions
}
}
iOS 15 finally adds a native UISheetPresentationController!
Official documentation
https://developer.apple.com/documentation/uikit/uisheetpresentationcontroller
I recently created a component called SwipeableView as subclass of UIView, written in Swift 5.1 . It support all 4 direction, has several customisation options and can animate and interpolate different attributes and items ( such as layout constraints, background/tint color, affine transform, alpha channel and view center, all of them demoed with the respective show case ). It also supports the swiping coordination with the inner scroll view if set or auto detected. Should be pretty easy and straightforward to be used ( I hope 🙂)
Link at https://github.com/LucaIaco/SwipeableView
proof of concept:
Hope it helps
If you are looking for a SwiftUI 2.0 solution that uses View Struct, here it is:
https://github.com/kenfai/KavSoft-Tutorials-iOS/tree/main/MapsBottomSheet
Maybe you can try my answer https://github.com/AnYuan/AYPannel, inspired by Pulley. Smooth transition from moving the drawer to scrolling the list. I added a pan gesture on the container scroll view, and set shouldRecognizeSimultaneouslyWithGestureRecognizer to return YES. More detail in my github link above. Wish to help.
Related
I have added a collectionView on top of a UITabBar but its touch is not working.The screeshot for the tabBar and collectionView
The code is attached below, I want the collectionView to be touchable. Here quickAccessView is the UIView that contains the collectionView. For constraints I'm using snapKit
override func viewWillLayoutSubviews() {
super.viewWillLayoutSubviews()
self.tabBar.bringSubviewToFront(quickAccessView)
}
private func setupQuickAccessView(){
print("this is tabBar's height", self.tabBar.frame.size.height)
self.tabBar.frame.size.height = 150
print("this is new tabBar's height", self.tabBar.frame.size.height)
self.tabBar.addSubview(quickAccessView)
quickAccessView.clipsToBounds = true
}
private func addQuickAccessViewConstraints(){
quickAccessView.snp.makeConstraints { make in
make.right.left.equalTo(self.tabBar.safeAreaLayoutGuide)
make.height.equalTo(76)
make.bottom.equalTo(self.tabBar.snp.bottom).offset(-80)
}
}
this is after modification that Aman told
The UITabBarController
final class MainTabBarController: UITabBarController {
private lazy var quickAccessView: QuickAccessView = .fromNib()
var quickAccessSupportedTabBar: QuickAccessSupportedTabBar {
self.tabBar as! QuickAccessSupportedTabBar // Even code is crashing here
}
// Even code is crashing here
override func viewDidLoad() {
super.viewDidLoad()
self.tabBar.backgroundColor = .white
}
override func viewDidAppear(_ animated: Bool) {
super.viewDidAppear(animated)
self.view.frame = self.quickAccessView.bounds
setupUI()
}
}
extension MainTabBarController{
private func setupUI(){
setupQuickAcessView()
addQuickAcessViewConstraints()
}
}
// MARK: - Setting Up Quick Access view
extension MainTabBarController {
private func setupQuickAcessView(){
self.quickAccessSupportedTabBar.addSubview(quickAccessView)
}
private func addQuickAcessViewConstraints(){
quickAccessView.snp.makeConstraints { make in
make.left.right.equalTo(self.quickAccessSupportedTabBar.safeAreaLayoutGuide)
make.height.equalTo(66)
make.bottom.equalTo(self.quickAccessSupportedTabBar.snp.top)
}
}
}
the UItabBar and here it is throwing error and I too am confuse that how to access it and convert it to points
class QuickAccessSupportedTabBar: UITabBar {
override public func hitTest(_ point: CGPoint, with event: UIEvent?) -> UIView? {
// if `quickAccessView` is visible, then convert `point` to its coordinate-system
// and check if it is within its bounds; if it is, then ask `quickAccessView`
// to perform the hit-test; you may skip the `isHidden` check, in-case this view
// is always present in your app; I'm assuming based on your screenshot that
// the user can dismiss / hide the `quickAccessView` using the cross icon
if !quickAccessView.isHidden {
// Convert the point to the target view's coordinate system.
// The target view isn't necessarily the immediate subview
let targetPoint = quickAccessView.convert(point, from: self)
if quickAccessView.bounds.contains(targetPoint) {
// The target view may have its view hierarchy, so call its
// hitTest method to return the right hit-test view
return quickAccessView.hitTest(targetPoint, with: event)
}
}
// else execute tabbar's default implementation
return super.hitTest(point, with: event)
}
}
I think what may be happening here is that since you've added quickAccessView as tab bar's subview, it is not accepting touches. This would be so because the tabbar's hist test will fail in this scenario.
To get around this, instead of using a UITabBar, subclass UITabBar, let us call it ToastyTabBar for reference. See the code below:
class ToastyTabBar: UITabBar {
override public func hitTest(_ point: CGPoint, with event: UIEvent?) -> UIView? {
// if `quickAccessView` is visible, then convert `point` to its coordinate-system
// and check if it is within its bounds; if it is, then ask `quickAccessView`
// to perform the hit-test; you may skip the `isHidden` check, in-case this view
// is always present in your app; I'm assuming based on your screenshot that
// the user can dismiss / hide the `quickAccessView` using the cross icon
if !quickAccessView.isHidden {
// Convert the point to the target view's coordinate system.
// The target view isn't necessarily the immediate subview
let targetPoint = quickAccessView.convert(point, from: self)
if quickAccessView.bounds.contains(targetPoint) {
// The target view may have its view hierarchy, so call its
// hitTest method to return the right hit-test view
return quickAccessView.hitTest(targetPoint, with: event)
}
}
// else execute tabbar's default implementation
return super.hitTest(point, with: event)
}
}
Set this as the class of your tabBar (both in the storyboard and the swift file), and then see if that solves it for you.
You'll have to figure out a way to make quickAccessView accessible to the tabbar for the hit test check. I haven't advised on that above because I'm not familiar with your class hierarchy, and how and where you set stuff up, but this should be trivial.
If this solves it for you, please consider marking this as the answer, and if it does not then please share a little more info here about where you're having the problem.
Edit (for someone using a UITabBarController):
In response to your comment about "how to access UITabBar class from UITabBarController" here's how I would go about it.
I'm assuming you have a storyboard with the UITabBarController.
The first step (ignore this step if you already have a UITabBarController custom subclass) is that you need to subclass UITabBarController. Let us call this class ToastyTabBarController for reference. Set this class on the UITabBarController in your storyboard using the identity inspector pane in xcode.
The second step is to set the class of the UITabBar in your storyboard as ToastyTabBar (feel free to name it something more 'professional' 😊).
This is to be done in the same storyboard, in your UITabBarController scene itself. It will show the tabBar under your UITabBarController, and you can set the custom class on it using the identity inspector pane just like earlier.
The next step is to expose a computed property on your custom UITabBarController class, as shown below.
var toastyTabBar: ToastyTabBar {
self.tabBar as! ToastyTabBar
}
And that's it. Now you have a property on your UITabBarController subclass which is of ToastyTabBar type and you can use this new property, toastyTabBar, however you require.
Hope this helps.
I know there are several posts on SE relating to this issue but I couldn't get around them to find a proper solution for my situation.
I've a map view inside a view controller. I'm presenting another view controller with modalPresentationStyle set as custom(housing the card view) on top of the map view VC:
What I want for this scenario is that the map view to still be able to recognise touches when the location card view is presented along with the location card still recognising touches inside itself. Like how Apple Maps functions when the below list view is presented.
I know I can't pass touches through view controllers but I can't decide in between:
dumping the location card into the map view which I'll highly dislike,
presenting the location card via addChildViewController which I'm not quite sure how to implement in order to achieve the effect I want.
This SE question gives a detailed answer and a small sample project on mimicking Apple Maps' interface although I still can't figure out how to solve my issue.
I went with the option of dumping the location card view into the map view. BUT I didn't like it.
The thing was that I didn't want any of the logic of the location card inside the map view. But at the same time, iOS didn't provided an infrastructure and touch transfer between view controllers is basically not possible and the suggested workarounds seemed hard to implement.
First off, I migrated the location card view from a view controller to a struct.
Then, I defined a protocol named LocationCardPresentable which when extended, requires Self to be of type MapVC. Therefore, inside the protocol extension, I can work like if I'm inside MapVC but actually not. The protocol extension has various methods for presenting and dismissing the location card which I can call from inside MapVC.
So I managed to fix this just now by using a combination of loadView() and point(inside) to replace the rootView in the presented ViewController.
First, make a subclass of UIView which you will use as your rootView in any ViewControllers where you want touches to be passed on the ViewControllers underneath:
IgnoreTouchesView
import UIKit
class IgnoreTouchesView: UIView {
override init(frame: CGRect) {
super.init(frame: frame)
}
required init?(coder aDecoder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
override func point(inside point: CGPoint, with event: UIEvent?) -> Bool {
for view in self.subviews {
if view.isKind(of: UIButton) {
let foundButtonView = view
if foundButtonView.isUserInteractionEnabled && !foundButtonView.isHidden && foundButtonView.point(inside: self.convert(point, to: foundButtonView), with: event) {
return true
}
}
}
return false
}
The point(inside) function checks if the user taps on any UIButtons in the OverlayVC, in that case touches should still be handled. Any other touches get passed on to the VC below. This could be done different by only ignoring the rootView but I haven't figured out quiet how to do this yet.
Then, in the VC that you want to present, add the following:
let ignoreView: IgnoreTouchesView = {
let view = IgnoreTouchesView(frame: .zero)
view.translatesAutoresizingMaskIntoConstraints = false
return view
}()
override func loadView() {
view = ignoreView
}
Now add the ViewControllers to your original ViewController:
lazy var overlayVC : OverlayVC = {
let vc = SongOverlayVC()
vc.view.translatesAutoresizingMaskIntoConstraints = false
vc.delegate = self
return vc
}()
viewDidLoad(){
view.addSubview(songOverlayVC.view)
}
And that's it :)
Let me know if you run into any issues.
I have been experimenting with custom interactive view controller presentation and dismissal (using a combination of UIPresentationController, UIPercentDrivenInteractiveTransition, UIViewControllerAnimatedTransitioning, and UIViewControllerTransitioningDelegate) and have mostly gotten things working well for my needs.
However, there is one common scenario that I've yet to find addressed in any of the tutorials or documentation that I've read, leading me to the following question:
...
What is the proper way of handling custom interactive view controller dismissal, via a pan gesture, when the dismissed view contains a UIScrollView (ie. UITableView, UICollectionView, WKWebView, etc)?
...
Basically, what I'd like is for the following:
View controllers are interactively dismissible by panning them down. This is common UX in many apps.
If the dismissed view controller contains a (vertically-scrolling) scroll view, panning down scrolls that view as expected until the user reaches the top, after which the scrolling ceases and the pan-to-dismiss occurs.
Scroll views should otherwise behave as normal.
I know that this is technically possible - I've seen it in other apps, such as Overcast and Apple's own Music app - but I've not been able to find the key to coordinating the behavior of my pan gesture with that of the scroll view(s).
Most of my own attempts center on trying to conditionally enable/disable the scrollview (or its associated pan gesture recognizer) based on its contentOffset.y while scrolling and having the view controller dismissal's pan gesture recognizer take over from there, but this has been fraught with problems and I fear that I am overthinking it.
I feel like the secret mostly lies in the following pan gesture recognizer delegate method:
func gestureRecognizer(_ gestureRecognizer: UIGestureRecognizer, shouldRecognizeSimultaneouslyWith otherGestureRecognizer: UIGestureRecognizer) -> Bool {
// ...
}
I have created a reduced sample project which should demonstrate the scenario more clearly. Any code suggestions are highly welcome!
https://github.com/Darchmare/SlidePanel-iOS
Solution
Make scrollView stop scrolling after it reached top by using UIScrollView's bounces property and scrollViewDidScroll(_:) method.
func scrollViewDidScroll(_ scrollView: UIScrollView) {
scrollView.bounces = (scrollView.contentOffset.y > 10);
}
Don't forget to set scrollView.delegate = self
Only handle panGestureRecognizer when scrollView reached top - It means when scrollView.contentOffset.y == 0 by using a protocol.
protocol PanelAnimationControllerDelegate {
func shouldHandlePanelInteractionGesture() -> Bool
}
ViewController
func shouldHandlePanelInteractionGesture() -> Bool {
return (scrollView.contentOffset.y == 0);
}
PanelInteractionController
class PanelInteractionController: ... {
var startY:CGFloat = 0
private weak var viewController: (UIViewController & PanelAnimationControllerDelegate)?
#objc func handlePanGestureRecognizer(_ gestureRecognizer: UIPanGestureRecognizer) {
switch gestureRecognizer.state {
case .began:
break
case .changed:
let translation = gestureRecognizer.translation(in: gestureRecognizer.view!.superview!)
let velocity = gestureRecognizer.velocity(in: gestureRecognizer.view!.superview)
let state = gestureRecognizer.state
// Don't do anything when |scrollView| is scrolling
if !(viewController?.shouldHandlePanelInteractionGesture())! && percentComplete == 0 {
return;
}
var rawProgress = CGFloat(0.0)
rawProgress = ((translation.y - startTransitionY) / gestureRecognizer.view!.bounds.size.height)
let progress = CGFloat(fminf(fmaxf(Float(rawProgress), 0.0), 1.0))
if abs(velocity.x) > abs(velocity.y) && state == .began {
// If the user attempts a pan and it looks like it's going to be mostly horizontal, bail - we don't want it... - JAC
return
}
if !self.interactionInProgress {
// Start to pan |viewController| down
self.interactionInProgress = true
startTransitionY = translation.y;
self.viewController?.dismiss(animated: true, completion: nil)
} else {
// If the user gets to a certain point within the dismissal and releases the panel, allow the dismissal to complete... - JAC
self.shouldCompleteTransition = progress > 0.2
update(progress)
}
case .cancelled:
self.interactionInProgress = false
startTransitionY = 0
cancel()
case .ended:
self.interactionInProgress = false
startTransitionY = 0
if self.shouldCompleteTransition == false {
cancel()
} else {
finish()
}
case .failed:
self.interactionInProgress = false
startTransitionY = 0
cancel()
default:
break;
}
}
}
Result
For more detail, you can take a look at my sample project
For me, this little bit of code answered a lot of my issues and greatly helped my custom transitions in scrollviews, it will hold a negative scrollview offset from moving while trying to start a transition or showing an activity indicator on the top. My guess is that this will solve at least some of your transition/animation hiccups:
func scrollViewDidEndDragging(_ scrollView: UIScrollView, willDecelerate decelerate: Bool) {
if scrollView.contentOffset.y < -75 {
scrollView.contentInset.top = -scrollView.contentOffset.y
}
// Do animation or transition
}
I believe you don't need an additional pan gesture recognizer to implement this. You can simply hook onto the different delegate methods of the scroll view to achieve the "pan to dismiss" effect. Here is how I went about it
// Set the dragging property to true
func scrollViewWillBeginDragging(_: UIScrollView) {
isDragging = true
}
func scrollViewDidScroll(_ scrollView: UIScrollView) {
// If not dragging, we could make an early exit
guard isDragging else {
return
}
let topOffset = scrollView.contentOffset.y + statusBarHeight
// If The dismissal has not already started and the user has scrolled to the top and they are currently scrolling, then initiate the interactive dismissal
if !isDismissing && topOffset <= 0 && scrollView.isTracking {
startInteractiveTransition()
return
}
// If its already being dismissed, then calculate the progress and update the interactive dismissal animator
if isDismissing {
updateInteractiveTransitionProgress()
}
}
// Once the scroll ends, check for a few things
func scrollViewWillEndDragging(_ scrollView: UIScrollView, withVelocity velocity: CGPoint, targetContentOffset: UnsafeMutablePointer<CGPoint>) {
// Early return
if !isDismissing {
return
}
// Optional check to dismiss the controller, if swiped from the top
checkForFastSwipes()
// If dragged enough, dismiss the controller, otherwise cancel the
transition
if interactor?.shouldFinish ?? false {
interactor?.finish()
} else {
interactor?.cancel()
}
// Finally reset the transition properties
resetTransitionProperties()
}
private func checkForFastSwipes() {
let velocity = scrollView.panGestureRecognizer.velocity(in: view)
let velDiff = velocity.y - velocity.x
if velDiff > 0 && velDiff >= 75 {
interactor?.hasStarted = false
self.dismiss()
interactor?.shouldFinish = true
}
}
private func startInteractiveTransition() {
isDismissing = true
interactor?.hasStarted = true
dismiss()
}
private func updateInteractiveTransitionProgress() {
progress = max(
0.0,
min(1.0, ((-scrollView.contentOffset.y) - statusBarHeight) / 90.0)
)
interactor?.shouldFinish = progress > 0.5
interactor?.update(progress)
}
private func resetTransitionProperties() {
isDismissing = false
isDragging = false
}
The interactor property used for synchronizing the animation with gesture
var interactor: Interactor?
class Interactor: UIPercentDrivenInteractiveTransition {
var hasStarted = false
var shouldFinish = false
}
Inspired by the following Kodeco tutorial
https://www.kodeco.com/books/ios-animations-by-tutorials/v6.0/chapters/25-uiviewpropertyanimator-view-controller-transitions
(Look for the Interactive view controller transitions section)
Edit
After implementing the solution below, I realized that it only works if you have sufficient content to scroll, however, if you have dynamic content wherein the contents are not guaranteed to be scrollable as was my case, you'd be better off adding a pan gesture as mentioned by #trungduc. However, there are a few improvements that we could make to their answer like detecting an upwards scroll and not letting it interfere with our gesture.
Under the changed state add the following code
let isUpwardsScroll = self.velocity(in: target).y < 0
/*
If the user is normally scrolling the view, ignore it. However,
once the interaction starts allow such gestures as they could be
dragging the interactable view back
*/
if isUpwardScroll && !interactor.hasStarted {
return
}
I have two view controllers and from the first one I show the second one by a modal segue, which presentation style is set to over current context. I also use blur effect which appears during the transition and disappears after it.
I've created a demo app to show how the transition looks like:
Here, the second view controller contains a UIScrollView, and on top of that, a yellow rectangle, which is another UIView with a UIButton on it. That UIButton also closes the view controller. Also, as you can see, I've set the background color to clear, so the blur effect is visible.
Now, in my project the transition is basically the same, except, my view controllers are "heavier".
The first view controller is embedded inside a UINavigationController" and a UITabBarController and on it I have a custom segmented control which
is made from UIViews and UIButtons, and a UITableView with custom cells.
The second view controller consists of a UIScrollView and a UIView (like on the image above, just bigger a little). That view contains a UIImageView, UILabels and a smaller UIView which is used as button to close the view by tapping on it.
Here is the code that I use to close the second view controller by dragging it down (UIScrollViewDelegate's methods).
extension AuthorInfoViewController: UIScrollViewDelegate {
func scrollViewWillBeginDragging(_ scrollView: UIScrollView) {
isDragging = true
}
func scrollViewDidScroll(_ scrollView: UIScrollView) {
guard isDragging else {
return
}
if !isDismissingAuthorInfo && scrollView.contentOffset.y < -30.0 && dismissAnimator != nil {
authoInfoViewControllerDelegate?.authorInfoViewControllerWillDismiss()
isDismissingAuthorInfo = true
dismissAnimator?.wantsInteractiveStart = true
dismiss(animated: true, completion: nil)
return
}
if isDismissingAuthorInfo {
let progress = max(0.0, min(1.0, ((-scrollView.contentOffset.y) - 30) / 90.0))
dismissAnimator?.update(progress)
}
}
func scrollViewWillEndDragging(_ scrollView: UIScrollView, withVelocity velocity: CGPoint, targetContentOffset: UnsafeMutablePointer<CGPoint>) {
let progress = max(0.0, min(1.0, ((-scrollView.contentOffset.y) - 30) / 90.0))
if progress > 0.5 {
dismissAnimator?.finish()
} else {
dismissAnimator?.cancel()
print("Canceled")
}
isDismissingAuthorInfo = false
isDragging = false
}
}
Here, isDismissingAuthorInfo and isDragging are booleans which keep
track whether the view is dismissing and is dragged at all. authorInfoViewControllerWillDismiss is a method implemented in a protocol to which conforms the first view controller. That methods calls another method which adds the blur animation to the custom transitions animator.
EDITED
The animator code is the following:
class DismissAnimator: UIPercentDrivenInteractiveTransition, UIViewControllerAnimatedTransitioning {
var auxAnimationsForBlur: (()->Void)?
var auxAnimationsForTabBar: (()->Void)?
var auxAnimationsCancelForBlur: (()->Void)?
var auxAnimationsCancelForTabBar: (()->Void)?
var tabBar: UITabBar?
var blurView: UIView?
let transitionDuration = 0.75
func transitionDuration(using transitionContext: UIViewControllerContextTransitioning?) -> TimeInterval {
return transitionDuration
}
func animateTransition(using transitionContext: UIViewControllerContextTransitioning) {
transitionAnimator(using: transitionContext).startAnimation()
}
func transitionAnimator(using transitionContext: UIViewControllerContextTransitioning) -> UIViewImplicitlyAnimating {
let duration = transitionDuration(using: transitionContext)
let container = transitionContext.containerView
let from = transitionContext.view(forKey: .from)!
container.addSubview(from)
let animator = UIViewPropertyAnimator(duration: duration, curve: .easeOut)
animator.addAnimations({
from.transform = CGAffineTransform(translationX: 0.0, y: container.frame.size.height + 30)
}, delayFactor: 0.15)
animator.addCompletion { (position) in
switch position {
case .end:
transitionContext.completeTransition(!transitionContext.transitionWasCancelled)
self.tabBar?.isHidden = false
self.blurView?.removeFromSuperview()
default:
transitionContext.completeTransition(false)
self.auxAnimationsCancelForBlur?()
self.auxAnimationsCancelForTabBar?()
}
}
if let auxAnimationsForBlur = auxAnimationsForBlur {
animator.addAnimations(auxAnimationsForBlur)
}
if let auxAnimationsForTabBar = auxAnimationsForTabBar {
animator.addAnimations(auxAnimationsForTabBar)
}
return animator
}
func interruptibleAnimator(using transitionContext: UIViewControllerContextTransitioning) -> UIViewImplicitlyAnimating {
return transitionAnimator(using:transitionContext)
}
}
In the code above, the auxAnimationsForBlur is for adding blur animation to the animator, the auxAnimationsCancelForBlur is for canceling it, auxAnimationsForTabBar is for adding the animation of alpha value of tabBar, auxAnimationsCancelForTabBar is for canceling it.
Now, the problem is the following: the animation works fine, but after running it by dragging the second view controller for several times (5-9, approximately), after the transition is over and the first view controller is shown, it just stops responding. However, on the bottom I have a tab bar, and it works. So, when I change to another tab and return back, I see the second view controller and a black screen behind it (where the first view controller should have been). When this happens the cancel method on UIPercentDrivenInteractiveTransition gets called, from scrollViewWillEndDragging method above (on the console I see the word cancel printed). Is it possible that cancel method on UIPercentDrivenInteractiveTransition doesn't causes this problem, because when I comment out the call to that method, it seems everything works ok (in that case, I also comment out the call to interruptibleAnimator(using:) method on my animator, so I lose the interactive behaviour of the transition)? I couldn't reproduce this behaviour while closing the second view controller by tapping on a close button, so I think it has something to do with dragging.
What could cause this problem, and what could you suggest for solving it? I would appreciate all your help.
I'd like to use the UIViewController's input accessory view like this:
override func canBecomeFirstResponder() -> Bool {
return true
}
override var inputAccessoryView: UIView! {
return self.bar
}
but the issue is that I have a drawer like view and when I slide the view open, the input view stays on the window. How can I keep the input view on the center view like Slack does it.
Where my input view stays at the bottom, taking up the full screen (the red is the input view in the image below):
There are two ways to do this exactly like Slack doing it, Meiwin has a medium post here A Stickler for Details: Implementing Sticky Input Field in iOS to show how he managed to do this which he actually puts an empty UIView as an inputAccessoryView then track it’s coordinates on screen to know where to put his custom view in relation with the empty view, this way can be helpful if you are going to support SplitViewController on iPad, but if you are not interested in this way, you can see how I managed to do this like this image
Here is before swiping
Here is after
All I did was actually taking a snapshot from the inputAccessoryView window and putting it on the NavigationController of the TableViewController
I am using SideMenu from Jon Kent and it’s pretty easy to do it with the UISideMenuNavigationControllerDelegate
var isInputAccessoryViewEnabled = true {
didSet {
self.inputAccessoryView?.isHidden = !self.isInputAccessoryViewEnabled
if self.isInputAccessoryViewEnabled {self.becomeFirstResponder()}
}
}
func sideMenuWillAppear(menu: UISideMenuNavigationController, animated: Bool) {
let inputWindow = UIApplication.shared.windows.filter({$0.className == "UITextEffectsWindow"}).first
self.inputAccessoryViewSnapShot = inputWindow?.snapshotView(afterScreenUpdates: false)
if let snapShotView = self.inputAccessoryViewSnapShot, let navView = self.navigationController?.view {
navView.addSubview(snapShotView)
}
self.isInputAccessoryViewEnabled = false
}
func sideMenuDidDisappear(menu: UISideMenuNavigationController, animated: Bool) {
self.inputAccessoryViewSnapShot?.removeFromSuperview()
self.isInputAccessoryViewEnabled = true
}
I hope that helps :)