在我的情况下，我需要一个 halfSize 视图控制器。我关注了this answer which worked great，直到我意识到我仍然需要能够与呈现的 vc（halfSizeVC 后面的 vc）进行交互。
关键是你必须将这两个帧设置为相同的 CGRect 值：
halfSizeVC.frame = CGRect(x: 0, y: UIScreen.main.bounds.height / 2, width: UIScreen.main.bounds.width, height: UIScreen.main.bounds.height)
containerView = CGRect(x: 0, y: UIScreen.main.bounds.height / 2, width: UIScreen.main.bounds.width, height: UIScreen.main.bounds.height)
这是从 ViewController 到 HalfSizeController 并使 HalfSizeController 屏幕大小为 1/2 的代码。即使在屏幕上显示halfSizeVC您仍然可以与 其后面的 vc 的上半部分进行交互。
如果您希望能够触摸 halfSizeVC 内部的某些东西，您还必须创建一个 PassthroughView 类。我把它放在了底部。
呈现的 vc 是白色的，底部有一个紫色按钮。点击紫色按钮会弹出红色 halfSizeVC。
vc/presentingVC:
import UIKit
class ViewController: UIViewController {
lazy var purpleButton: UIButton = {
let button = UIButton(type: .system)
button.translatesAutoresizingMaskIntoConstraints = false
button.setTitle("Tap to Present HalfSizeVC", for: .normal)
button.setTitleColor(UIColor.white, for: .normal)
button.backgroundColor = UIColor.systemPurple
button.addTarget(self, action: #selector(purpleButtonPressed), for: .touchUpInside)
button.layer.cornerRadius = 7
button.layer.masksToBounds = true
return button
}()
var halfSizeVC: HalfSizeController?
override func viewDidLoad() {
super.viewDidLoad()
view.backgroundColor = .white
// tap gesture on vc will dismiss HalfSizeVC
let tapGesture = UITapGestureRecognizer(target: self, action: #selector(dismissHalfSizeVC))
view.addGestureRecognizer(tapGesture)
}
// tapping the purple button presents HalfSizeVC
@objc func purpleButtonPressed() {
halfSizeVC = HalfSizeController()
// *** IMPORTANT ***
halfSizeVC!.view.frame = CGRect(x: 0, y: 0, width: UIScreen.main.bounds.width, height: UIScreen.main.bounds.height / 2)
halfSizeVC!.modalPresentationStyle = .custom
present(halfSizeVC!, animated: true, completion: nil)
}
// dismiss HalfSizeVC by tapping anywhere on the white background
@objc func dismissHalfSizeVC() {
halfSizeVC?.dismissVC()
}
}
halfSizeVC/presentedVC
import UIKit
class HalfSizeController: UIViewController {
init() {
super.init(nibName: nil, bundle: nil)
modalPresentationStyle = .custom
transitioningDelegate = self
}
required init?(coder aDecoder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
lazy var topHalfDummyView: PassthroughView = {
let view = PassthroughView()
view.translatesAutoresizingMaskIntoConstraints = false
view.backgroundColor = .clear
view.isUserInteractionEnabled = true
return view
}()
var isPresenting = false
let halfScreenHeight = UIScreen.main.bounds.height / 2
override func viewDidLoad() {
super.viewDidLoad()
view.backgroundColor = .red
setAnchors()
}
private func setAnchors() {
view.addSubview(topHalfDummyView)
topHalfDummyView.bottomAnchor.constraint(equalTo: view.bottomAnchor).isActive = true
topHalfDummyView.leadingAnchor.constraint(equalTo: view.leadingAnchor).isActive = true
topHalfDummyView.trailingAnchor.constraint(equalTo: view.trailingAnchor).isActive = true
topHalfDummyView.heightAnchor.constraint(equalToConstant: halfScreenHeight).isActive = true
}
public func dismissVC() {
dismiss(animated: true, completion: nil)
}
}
extension HalfSizeController: 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
// *** IMPORTANT ***
containerView.frame = CGRect(x: 0, y: halfScreenHeight, width: UIScreen.main.bounds.width, height: halfScreenHeight)
let toViewController = transitionContext.viewController(forKey: UITransitionContextViewControllerKey.to)
guard let toVC = toViewController else { return }
isPresenting = !isPresenting
if isPresenting == true {
containerView.addSubview(toVC.view)
topHalfDummyView.frame.origin.y += halfScreenHeight
UIView.animate(withDuration: 0.4, delay: 0, options: [.curveEaseOut], animations: {
self.topHalfDummyView.frame.origin.y -= self.halfScreenHeight
}, completion: { (finished) in
transitionContext.completeTransition(true)
})
} else {
UIView.animate(withDuration: 0.4, delay: 0, options: [.curveEaseOut], animations: {
}, completion: { (finished) in
self.topHalfDummyView.frame.origin.y += self.halfScreenHeight
transitionContext.completeTransition(true)
})
}
}
}
HalfSizeVC 中的 topHalfDummyView 需要 PassthroughView
import UIKit
class PassthroughView: UIView {
override func point(inside point: CGPoint, with event: UIEvent?) -> Bool {
print("Passing all touches to the next view (if any), in the view stack.")
return false
}
}
按下紫色按钮之前：
按下紫色按钮后：
如果你按下白色背景，红色会消失
您只需 c+p 所有 3 个文件并运行您的项目