I am trying to present modal view controller on other viewcontroller sized to half parent view controller. But it always present in full screen view.
I have created freeform sized View controller in my storyboard with fixed frame size. 320 X 250.
var storyboard = UIStoryboard(name: "Main", bundle: nil)
var pvc = storyboard.instantiateViewControllerWithIdentifier("CustomTableViewController") as ProductsTableViewController
self.presentViewController(pvc, animated: true, completion: nil)
I have tried to set frame.superview and it doesn't help.
Please advice.
You can use a UIPresentationController to achieve this.
For this you let the presenting ViewController implement the UIViewControllerTransitioningDelegate and return your PresentationController for the half sized presentation:
func presentationControllerForPresentedViewController(presented: UIViewController, presentingViewController presenting: UIViewController!, sourceViewController source: UIViewController) -> UIPresentationController? {
return HalfSizePresentationController(presentedViewController: presented, presentingViewController: presenting)
}
When presenting you set the presentation style to .Custom and set your transitioning delegate:
pvc.modalPresentationStyle = UIModalPresentationStyle.Custom
pvc.transitioningDelegate = self
The presentation controller only returns the frame for your presented view controller:
class HalfSizePresentationController : UIPresentationController {
override func frameOfPresentedViewInContainerView() -> CGRect {
return CGRect(x: 0, y: 0, width: containerView.bounds.width, height: containerView.bounds.height/2)
}
}
Here is the working code in its entirety:
class ViewController: UIViewController, UIViewControllerTransitioningDelegate {
@IBAction func tap(sender: AnyObject) {
var storyboard = UIStoryboard(name: "Main", bundle: nil)
var pvc = storyboard.instantiateViewControllerWithIdentifier("CustomTableViewController") as UITableViewController
pvc.modalPresentationStyle = UIModalPresentationStyle.Custom
pvc.transitioningDelegate = self
pvc.view.backgroundColor = UIColor.redColor()
self.presentViewController(pvc, animated: true, completion: nil)
}
func presentationControllerForPresentedViewController(presented: UIViewController, presentingViewController presenting: UIViewController!, sourceViewController source: UIViewController) -> UIPresentationController? {
return HalfSizePresentationController(presentedViewController: presented, presentingViewController: presentingViewController)
}
}
class HalfSizePresentationController : UIPresentationController {
override func frameOfPresentedViewInContainerView() -> CGRect {
return CGRect(x: 0, y: 0, width: containerView.bounds.width, height: containerView.bounds.height/2)
}
}
It would be a a clean architect if you push some delegate method of UIViewControllerTransitioningDelegate in your ViewController that want to be present half modal.
Assuming we have ViewControllerA present ViewControllerB with half modal.
in ViewControllerA just present ViewControllerB with custom modalPresentationStyle
func gotoVCB(_ sender: UIButton) {
let vc = ViewControllerB()
vc.modalPresentationStyle = .custom
present(vc, animated: true, completion: nil)
}
And in ViewControllerB:
import UIKit
final class ViewControllerB: UIViewController {
lazy var backdropView: UIView = {
let bdView = UIView(frame: self.view.bounds)
bdView.backgroundColor = UIColor.black.withAlphaComponent(0.5)
return bdView
}()
let menuView = UIView()
let menuHeight = UIScreen.main.bounds.height / 2
var isPresenting = false
init() {
super.init(nibName: nil, bundle: nil)
modalPresentationStyle = .custom
transitioningDelegate = self
}
required init?(coder aDecoder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
override func viewDidLoad() {
super.viewDidLoad()
view.backgroundColor = .clear
view.addSubview(backdropView)
view.addSubview(menuView)
menuView.backgroundColor = .red
menuView.translatesAutoresizingMaskIntoConstraints = false
menuView.heightAnchor.constraint(equalToConstant: menuHeight).isActive = true
menuView.bottomAnchor.constraint(equalTo: view.bottomAnchor).isActive = true
menuView.leadingAnchor.constraint(equalTo: view.leadingAnchor).isActive = true
menuView.trailingAnchor.constraint(equalTo: view.trailingAnchor).isActive = true
let tapGesture = UITapGestureRecognizer(target: self, action: #selector(ViewControllerB.handleTap(_:)))
backdropView.addGestureRecognizer(tapGesture)
}
func handleTap(_ sender: UITapGestureRecognizer) {
dismiss(animated: true, completion: nil)
}
}
extension ViewControllerB: UIViewControllerTransitioningDelegate, UIViewControllerAnimatedTransitioning {
func animationController(forPresented presented: UIViewController, presenting: UIViewController, source: UIViewController) -> UIViewControllerAnimatedTransitioning? {
return self
}
func animationController(forDismissed dismissed: UIViewController) -> UIViewControllerAnimatedTransitioning? {
return self
}
func transitionDuration(using transitionContext: UIViewControllerContextTransitioning?) -> TimeInterval {
return 1
}
func animateTransition(using transitionContext: UIViewControllerContextTransitioning) {
let containerView = transitionContext.containerView
let toViewController = transitionContext.viewController(forKey: UITransitionContextViewControllerKey.to)
guard let toVC = toViewController else { return }
isPresenting = !isPresenting
if isPresenting == true {
containerView.addSubview(toVC.view)
menuView.frame.origin.y += menuHeight
backdropView.alpha = 0
UIView.animate(withDuration: 0.4, delay: 0, options: [.curveEaseOut], animations: {
self.menuView.frame.origin.y -= self.menuHeight
self.backdropView.alpha = 1
}, completion: { (finished) in
transitionContext.completeTransition(true)
})
} else {
UIView.animate(withDuration: 0.4, delay: 0, options: [.curveEaseOut], animations: {
self.menuView.frame.origin.y += self.menuHeight
self.backdropView.alpha = 0
}, completion: { (finished) in
transitionContext.completeTransition(true)
})
}
}
}
The result:
All code is published at my Github
Just in case someone is looking to do this with Swift 4, as I was.
class MyViewController : UIViewController {
...
@IBAction func dictionaryButtonTouchUp(_ sender: UIButton) {
let modalViewController = ...
modalViewController.transitioningDelegate = self
modalViewController.modalPresentationStyle = .custom
self.present(modalViewController, animated: true, completion: nil)
}
}
extension MyViewController : UIViewControllerTransitioningDelegate {
func presentationController(forPresented presented: UIViewController, presenting: UIViewController?, source: UIViewController) -> UIPresentationController? {
return HalfSizePresentationController(presentedViewController: presented, presenting: presenting)
}
}
Where the HalfSizePresentationController class is composed of:
class HalfSizePresentationController : UIPresentationController {
override var frameOfPresentedViewInContainerView: CGRect {
get {
guard let theView = containerView else {
return CGRect.zero
}
return CGRect(x: 0, y: theView.bounds.height/2, width: theView.bounds.width, height: theView.bounds.height/2)
}
}
}
Cheers!
Jannis captured the overall strategy well. It didn't work for me in iOS 9.x with swift 3. On the presenting VC, the action to launch the presented VC is similar to what was presented above with some very minor changes as below:
let storyboard = UIStoryboard(name: "Main", bundle: nil)
let pvc = storyboard.instantiateViewController(withIdentifier: "SomeScreen") as SomeViewController
pvc.modalPresentationStyle = .custom
pvc.transitioningDelegate = self
present(pvc, animated: true, completion: nil)
To implement UIViewControllerTransitioningDelegate on the same presenting VC, the syntax is quite different as highlighted in SO answer in https://stackoverflow.com/a/39513247/2886158. This is was the most tricky part for me. Here is the protocol implementation:
func presentationController(forPresented presented: UIViewController, presenting: UIViewController?, source: UIViewController) -> UIPresentationController? {
return HalfSizePresentationController(presentedViewController:presented, presenting: presenting)
}
For the UIPresentationController class, I had to override the variable frameOfPresentedViewInContainerView, not method, as below:
class HalfSizePresentationController: UIPresentationController {
override var frameOfPresentedViewInContainerView: CGRect {
return CGRect(x: 0, y: 0, width: containerView!.bounds.width, height: containerView!.bounds.height/2)
}
}
There were some questions about how to dismiss the view after presentation. You can implement all the usual logic on your presented VC like any other VC. I implementation an action to dismiss the view in SomeViewController when a user tabs outside the presented VC.
To add to Jannis' answer:
In case your pop-view is a UIViewController to which you ADD a Table on load/setup, you will need to ensure that the table frame you create matches the desired width of the actual view.
For example:
let tableFrame: CGRect = CGRectMake(0, 0, chosenWidth, CGFloat(numOfRows) * rowHeight)
where chosenWidth is the width you set in your custom class (in the above: containerView.bounds.width)
You do not need to enforce anything on the Cell itself as the table container (at least in theory) should force the cell to the right width.
I use below logic to present half screen ViewController
let storyboard = UIStoryboard(name: "Main", bundle: nil)
let expVC = storyboard.instantiateViewController(withIdentifier: "AddExperinceVC") as! AddExperinceVC
expVC.modalPresentationStyle = UIModalPresentationStyle.overCurrentContext
self.present(expVC, animated: true, completion: nil)
来源：https://stackoverflow.com/questions/29219688/present-modal-view-controller-in-half-size-parent-controller