How to build a context menu like Facebook / Slack on iOS? - ios

Question

I was just looking at Context menu of Facebook and or slack and wanted to create something similar in my App.
I have tried two methods.
First method. Having a in View Table View and sliding it from bottom to create as if it is animated on to the view. But the problem with this is that The navigation controller and Tab bar controller are not hidden and a white patch is shown over the Black (Alpha 30 %).
The second method I tried was showing a new View controller over the current view controller and presenting as a Modal presentation.
let vc = CustomActionTableViewController(nibName: "CustomActionTableViewController", bundle: nil)
vc.modalPresentationStyle = .overFullScreen
self.present(vc, animated: false, completion: nil)
This works okay but the method is too slow as I have to work with lot of Notifications (To send selected index to my main View and then perform action). It is painfully slow.
Could anyone help me with how I can improve the implementation so that I can get the Action sheet similar to Facebook which is smooth and very very fluid

Answer 1

Check this example : Bottom pop Up
Currently I am using this in my app and it's work fine.

Answer 2

Since you mentioned Slack, they actually have open sourced their bottom sheet implementation, PanModal.

Answer 3

Using UIPresentationController and UIPanGestureRecognizer
1- create BottomMenu presentation Controller which will handle the height of your View Controller and blur
class BottomMenuPresentationController: UIPresentationController {
// MARK: - Properties
var blurEffectView: UIVisualEffectView?
var tapGestureRecognizer = UITapGestureRecognizer()
private var topHeightRatio: Float
private var bottomHeightRatio: Float
init(presentedViewController: UIViewController, presenting presentingViewController: UIViewController?, topHeightRatio: Float, bottomHeightRatio: Float) {
let blurEffect = UIBlurEffect(style: .systemThickMaterialDark)
blurEffectView = UIVisualEffectView(effect: blurEffect)
self.topHeightRatio = topHeightRatio
self.bottomHeightRatio = bottomHeightRatio
super.init(presentedViewController: presentedViewController, presenting: presentingViewController)
blurEffectView?.autoresizingMask = [.flexibleWidth, .flexibleHeight]
tapGestureRecognizer = UITapGestureRecognizer(target: self, action: #selector(dismissController))
self.blurEffectView?.isUserInteractionEnabled = true
self.blurEffectView?.addGestureRecognizer(tapGestureRecognizer)
}
override var frameOfPresentedViewInContainerView: CGRect {
CGRect(origin: CGPoint(x: 0, y: self.containerView!.frame.height * CGFloat(topHeightRatio)),
size: CGSize(width: self.containerView!.frame.width, height: self.containerView!.frame.height * CGFloat(bottomHeightRatio)))
}
override func presentationTransitionWillBegin() {
self.blurEffectView?.alpha = 0
if let blurEffectView = blurEffectView {
self.containerView?.addSubview(blurEffectView)
}
self.presentedViewController.transitionCoordinator?.animate(alongsideTransition: { (_) in
self.blurEffectView?.alpha = 0.66
}, completion: { (_) in })
}
override func dismissalTransitionWillBegin() {
self.presentedViewController.transitionCoordinator?.animate(alongsideTransition: { (_) in
self.blurEffectView?.alpha = 0
}, completion: { (_) in
self.blurEffectView?.removeFromSuperview()
})
}
override func containerViewWillLayoutSubviews() {
super.containerViewWillLayoutSubviews()
presentedView!.roundCorners([.topLeft, .topRight], radius: 14)
}
override func containerViewDidLayoutSubviews() {
super.containerViewDidLayoutSubviews()
presentedView?.frame = frameOfPresentedViewInContainerView
blurEffectView?.frame = containerView!.bounds
}
#objc func dismissController() {
self.presentedViewController.dismiss(animated: true, completion: nil)
}
}
2- create Your ViewController
class BottomMenuVC: UIViewController {
// MARK: - Instances
var hasSetPointOrigin = false
var pointOrigin: CGPoint?
// MARK: - Properties
let topDarkLine: UIView = {
let view = UIView()
view.backgroundColor = UIColor(hexString: "#E1E1E1")
view.layer.cornerRadius = 2
return view
}()
let cancelButn: UIButton = {
let button = UIButton(type: .custom)
button.setAttributedTitle(NSAttributedString(string: "Cancel", attributes: [NSAttributedString.Key.font: UIFont.LatoMedium(size: 17),
NSAttributedString.Key.foregroundColor: UIColor(hexString: "#515151")
]), for: .normal)
button.backgroundColor = UIColor(hexString: "#F1F3F4")
button.layer.cornerRadius = 5.0
button.addTarget(self, action: #selector(cancelButnPressed), for: .touchUpInside)
return button
}()
// MARK: - viewLifeCycle
override func viewDidLoad() {
super.viewDidLoad()
view.backgroundColor = .white
view.isUserInteractionEnabled = true
setupMenuView()
}
override func viewDidLayoutSubviews() {
if !hasSetPointOrigin {
hasSetPointOrigin = true
pointOrigin = self.view.frame.origin
}
}
// MARK: - SetupView
func setupMenuView() {
self.view.addSubview(topDarkLine)
self.view.addSubview(cancelButn)
let panGesture = UIPanGestureRecognizer(target: self, action: #selector(panGestureRecognizerAction(_:)))
view.addGestureRecognizer(panGesture)
topDarkLine.constrainHeight(constant: 4)
topDarkLine.constrainWidth(constant: view.frame.size.width * 0.10)
topDarkLine.centerXInSuperview()
topDarkLine.anchor(top: view.topAnchor, leading: nil, bottom: nil, trailing: nil, padding: .init(top: 8, left: 0, bottom: 0, right: 0))
cancelButn.anchor(top:view.topAnchor, leading: view.leadingAnchor, bottom: nil, trailing: view.trailingAnchor,
padding: .init(top: 16, left: 16, bottom: 0, right: 16))
cancelButn.constrainHeight(constant: 44)
}
// MARK: - Actions
#objc func panGestureRecognizerAction(_ sender: UIPanGestureRecognizer) {
let translation = sender.translation(in: view)
// Not allowing the user to drag the view upward
guard translation.y >= 0 else { return }
// setting x as 0 because we don't want users to move the frame side ways!! Only want straight up or down in the y-axis
view.frame.origin = CGPoint(x: 0, y: self.pointOrigin!.y + translation.y)
if sender.state == .ended {
let dragVelocity = sender.velocity(in: view)
if dragVelocity.y >= 1300 {
// Velocity fast enough to dismiss the uiview
self.dismiss(animated: true, completion: nil)
} else {
// If the dragging isn’t too fast, resetting the view back to it’s original point
UIView.animate(withDuration: 0.3) {
self.view.frame.origin = self.pointOrigin ?? CGPoint(x: 0, y: 400)
}
}
}
}
#objc func cancelButnPressed() {
dismiss(animated: true, completion: nil)
}
}
3- make the viewController that contain the button that will present your menu conforms to UIViewControllerTransitioningDelegate
extension viewController: UIViewControllerTransitioningDelegate {
func presentationController(forPresented presented: UIViewController, presenting: UIViewController?, source: UIViewController) -> UIPresentationController? {
BottomMenuPresentationController(presentedViewController: presented, presenting: presenting, topHeightRatio: 0.6, bottomHeightRatio: 0.4)
}
}
4- set the transitioning delegate to self and present your custom presentation Controller
func showBottomMenu() {
let menu = BottomMenuVC()
menu.coordinator = self
menu.modalPresentationStyle = .custom
menu.transitioningDelegate = self
present(menu, animated: true, completion: nil)
}
check this PanGesture Slidable View article