我已经尝试了一段时间，但我无法弄清楚如何创建一个撰写动画，iOS 10+当您可以将新撰写的电子邮件向下拖动时，它会停留在底部并且应用程序的其余部分可以正常访问，然后当您点击它，它会重新显示。
我创建了一个示例项目，其中我有一个UIViewController展示另一个UIViewController其中有一个触发状态分析器UIPanGestureRecognizer的示例项目。UINavigationControllerpangesture
我确实可以拖动以将其关闭，但我找不到保持框架的方法。
Bellow有一个我正在尝试完成的打印屏幕，然后是我使用的代码到我被困在的地方。
UIViewController那是presentingViewController类
//
// ViewController.swift
// dismissLayerTest
//
// Created by Ivan Cantarino on 27/09/17.
// Copyright © 2017 Ivan Cantarino. All rights reserved.
//
import UIKit
class ViewController: UIViewController, UIViewControllerTransitioningDelegate {
@objc let interactor = Interactor()
lazy var presentButton: UIButton = {
let b = UIButton(type: .custom)
b.setTitle("Present", for: .normal)
b.setTitleColor(.black, for: .normal)
b.addTarget(self, action: #selector(didTapPresentButton), for: .touchUpInside)
return b
}()
lazy var testbutton: UIButton = {
let b = UIButton(type: .custom)
b.setTitle("test", for: .normal)
b.setTitleColor(.black, for: .normal)
b.addTarget(self, action: #selector(test), for: .touchUpInside)
return b
}()
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view, typically from a nib.
view.backgroundColor = .white
view.addSubview(presentButton)
presentButton.anchor(top: nil, left: nil, bottom: nil, right: nil, paddingTop: 0, paddinfLeft: 0, paddingBottom: 0, paddingRight: 0, width: 100, height: 100)
presentButton.centerXAnchor.constraint(equalTo: view.centerXAnchor).isActive = true
presentButton.centerYAnchor.constraint(equalTo: view.centerYAnchor).isActive = true
view.addSubview(testbutton)
testbutton.anchor(top: nil, left: nil, bottom: presentButton.topAnchor, right: nil, paddingTop: 0, paddinfLeft: 0, paddingBottom: 100, paddingRight: 0, width: 100, height: 100)
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
@objc func didTapPresentButton() {
let presentedVC = PresentedViewController()
let navController = UINavigationController(rootViewController: presentedVC)
navController.transitioningDelegate = self
presentedVC.interactor = interactor // new
navController.modalPresentationStyle = .custom
navController.view.layer.masksToBounds = true
present(navController, animated: true, completion: nil)
}
@objc func test() {
print("test")
}
// Handles the presenting animation
func animationController(forPresented presented: UIViewController, presenting: UIViewController, source: UIViewController) -> UIViewControllerAnimatedTransitioning? {
return CustomAnimationForPresentor()
}
// Handles the dismissing animation
func animationController(forDismissed dismissed: UIViewController) -> UIViewControllerAnimatedTransitioning? {
return CustomAnimationForDismisser()
}
// interaction controller, only for dismissing the view;
func interactionControllerForDismissal(using animator: UIViewControllerAnimatedTransitioning) -> UIViewControllerInteractiveTransitioning? {
return interactor.hasStarted ? interactor : nil
}
// delegate do custom modal presentation style
func presentationController(forPresented presented: UIViewController, presenting: UIViewController?, source: UIViewController) -> UIPresentationController? {
return CustomPresentationController(presentedViewController: presented, presenting: presenting)
}
}
UIViewController2 那是presentedViewController
import Foundation
import UIKit
class PresentedViewController: UIViewController, UIViewControllerTransitioningDelegate, UIGestureRecognizerDelegate {
@objc var interactor: Interactor? = nil
@objc var panGr = UIPanGestureRecognizer()
@objc var panTapRecon = UITapGestureRecognizer()
override func viewDidLoad() {
super.viewDidLoad()
view.backgroundColor = .green
let leftB = UIBarButtonItem(barButtonSystemItem: .cancel, target: self, action: #selector(didTapCancel))
navigationItem.leftBarButtonItem = leftB
panGr = UIPanGestureRecognizer(target: self, action: #selector(handleGesture))
navigationController?.navigationBar.addGestureRecognizer(panGr)
panTapRecon = UITapGestureRecognizer(target: self, action: #selector(handleNavControllerTapGR))
navigationController?.navigationBar.addGestureRecognizer(panTapRecon)
}
@objc func didTapCancel() {
guard let interactor = interactor else { return }
interactorFinish(interactor: interactor)
dismiss(animated: true, completion: nil)
}
@objc func handleNavControllerTapGR(_ sender: UITapGestureRecognizer) {
print("tap detected")
}
// Swipe gesture recognizer handler
@objc func handleGesture(_ sender: UIPanGestureRecognizer) {
//percentThreshold: This variable sets how far down the user has to drag
//in order to trigger the modal dismissal. In this case, it’s set to 40%.
let percentThreshold:CGFloat = 0.30
// convert y-position to downward pull progress (percentage)
let translation = sender.translation(in: view)
let verticalMovement = translation.y / view.bounds.height
let downwardMovement = fmaxf(Float(verticalMovement), 0.0)
let downwardMovementPercent = fminf(downwardMovement, 1.0)
let progress = CGFloat(downwardMovementPercent)
guard let interactor = interactor else { return }
switch sender.state {
case .began:
interactor.hasStarted = true
self.dismiss(animated: true, completion: nil)
case .changed:
// alterar se o tamanho do presentigViewController (MainTabBarController) for alterado no background
let scaleX = 0.95 + (progress * (1 - 0.95))
let scaleY = 0.95 + (progress * (1 - 0.95))
// Não deixa ultrapassar os 100% de scale (tamanho original)
if (scaleX > 1 && scaleY > 1) { return }
presentingViewController?.view.transform = CGAffineTransform.identity.scaledBy(x: scaleX, y: scaleY);
presentingViewController?.view.layer.masksToBounds = true
interactor.shouldFinish = progress > percentThreshold
interactor.update(progress)
case .cancelled:
interactor.hasStarted = false
interactor.cancel()
case .ended:
interactor.hasStarted = false
if (interactor.shouldFinish) {
interactorFinish(interactor: interactor)
} else {
// repõe o MainTabBarController na posição dele atrás do NewPostController
UIView.animate(withDuration: 0.5, animations: {
self.presentingViewController?.view.transform = CGAffineTransform.identity.scaledBy(x: 0.95, y: 0.95);
self.presentingViewController?.view.layer.masksToBounds = true
let c = UIColor.black.withAlphaComponent(0.4)
let shadowView = self.presentingViewController?.view.viewWithTag(999)
shadowView?.backgroundColor = c
})
interactor.cancel()
}
default: break
}
}
@objc func interactorFinish(interactor: Interactor) {
removeShadow()
interactor.finish()
}
// remove a shadow view
@objc func removeShadow() {
UIView.animate(withDuration: 0.2, animations: {
self.presentingViewController?.view.transform = CGAffineTransform.identity.scaledBy(x: 1.0, y: 1.0);
self.presentingViewController?.view.layer.masksToBounds = true
}) { _ in
}
}
}
这是一个包含自定义演示文稿的 Helper 文件：
//
// Helper.swift
// dismissLayerTest
//
// Created by Ivan Cantarino on 27/09/17.
// Copyright © 2017 Ivan Cantarino. All rights reserved.
//
import Foundation
import UIKit
class Interactor: UIPercentDrivenInteractiveTransition {
@objc var hasStarted = false
@objc var shouldFinish = false
}
extension UIView {
@objc func anchor(top: NSLayoutYAxisAnchor?, left: NSLayoutXAxisAnchor?, bottom: NSLayoutYAxisAnchor?, right: NSLayoutXAxisAnchor?, paddingTop: CGFloat, paddinfLeft: CGFloat, paddingBottom: CGFloat, paddingRight: CGFloat, width: CGFloat, height: CGFloat) {
translatesAutoresizingMaskIntoConstraints = false
if let top = top {
topAnchor.constraint(equalTo: top, constant: paddingTop).isActive = true
}
if let left = left {
leftAnchor.constraint(equalTo: left, constant: paddinfLeft).isActive = true
}
if let bottom = bottom {
bottomAnchor.constraint(equalTo: bottom, constant: -paddingBottom).isActive = true
}
if let right = right {
rightAnchor.constraint(equalTo: right, constant: -paddingRight).isActive = true
}
if width != 0 {
widthAnchor.constraint(equalToConstant: width).isActive = true
}
if height != 0 {
heightAnchor.constraint(equalToConstant: height).isActive = true
}
}
@objc func roundCorners(corners:UIRectCorner, radius: CGFloat) {
let path = UIBezierPath(roundedRect: self.bounds, byRoundingCorners: corners, cornerRadii: CGSize(width: radius, height: radius))
let mask = CAShapeLayer()
mask.path = path.cgPath
self.layer.mask = mask
}
}
class CustomAnimationForDismisser: NSObject, UIViewControllerAnimatedTransitioning {
// Tempo da animação
func transitionDuration(using transitionContext: UIViewControllerContextTransitioning?) -> TimeInterval {
return 0.27
}
func animateTransition(using transitionContext: UIViewControllerContextTransitioning) {
// Get the set of relevant objects.
let containerView = transitionContext.containerView
guard let fromVC = transitionContext.viewController(forKey: UITransitionContextViewControllerKey.from) else {
print("Returning animateTransition VC")
return
}
// from view só existe no dismiss
guard let fromView = transitionContext.view(forKey: UITransitionContextViewKey.from) else {
print("Failed to instantiate fromView: CustomAnimationForDismisser()")
return
}
// Set up some variables for the animation.
let containerFrame: CGRect = containerView.frame
var fromViewFinalFrame: CGRect = transitionContext.finalFrame(for: fromVC)
fromViewFinalFrame = CGRect(x: 0, y: containerFrame.size.height, width: containerFrame.size.width, height: containerFrame.size.height)
// Animate using the animator's own duration value.
UIView.animate(withDuration: 0.4, delay: 0, options: .curveEaseOut, animations: {
fromView.frame = fromViewFinalFrame
}) { (finished) in
let success = !(transitionContext.transitionWasCancelled)
// Notify UIKit that the transition has finished
transitionContext.completeTransition(success)
}
}
}
class CustomAnimationForPresentor: NSObject, UIViewControllerAnimatedTransitioning {
// Tempo da animação
func transitionDuration(using transitionContext: UIViewControllerContextTransitioning?) -> TimeInterval {
return 0.2
}
func animateTransition(using transitionContext: UIViewControllerContextTransitioning) {
// Get the set of relevant objects.
let containerView = transitionContext.containerView
// obtém os VCs para não o perder na apresentação (default desaparece por trás)
guard let fromVC = transitionContext.viewController(forKey: UITransitionContextViewControllerKey.from) else {//, let toVC = transitionContext.viewController(forKey: UITransitionContextViewControllerKey.to) else {
print("Returning animateTransition VC")
return
}
// gets the view of the presented object
guard let toView = transitionContext.view(forKey: UITransitionContextViewKey.to) else { return }
// Set up animation parameters.
toView.transform = CGAffineTransform(translationX: 0, y: containerView.bounds.height)
// Always add the "to" view to the container.
containerView.addSubview(toView)
// Animate using the animator's own duration value.
UIView.animate(withDuration: 0.35, delay: 0, options: .curveEaseOut, animations: {
// Zooms out da MainTabBarController - o VC
fromVC.view.transform = CGAffineTransform(scaleX: 0.95, y: 0.95)
// propriedades declaradas no CustomPresentationController() // Anima o presented view
toView.transform = .identity
}, completion: { (finished) in
let success = !(transitionContext.transitionWasCancelled)
// So it avoids view stacks and overlap issues
if (!success) { toView.removeFromSuperview() }
// Notify UIKit that the transition has finished
transitionContext.completeTransition(success)
})
}
}
class CustomPresentationController: UIPresentationController {
override init(presentedViewController: UIViewController, presenting presentingViewController: UIViewController!) {
super.init(presentedViewController: presentedViewController, presenting: presentingViewController)
}
// Tamanho desejado para o NewPostController
override var frameOfPresentedViewInContainerView: CGRect {
guard let containerBounds = containerView?.bounds else {
print("Failed to instantiate container bounds: CustomPresentationController")
return .zero
}
return CGRect(x: 0.0, y: 0.0, width: containerBounds.width, height: containerBounds.height)
}
// Garante que o frame do view controller a mostrar, se mantém conforme desenhado na função frameOfPresentedViewInContainerView
override func containerViewWillLayoutSubviews() {
presentedView?.frame = frameOfPresentedViewInContainerView
}
}
这种期望的效果也可以在其他应用程序中看到，例如Music app，Stack Exchange/Overflow iOS App
有没有人暗示如何做到这一点？我觉得我真的很接近实现它，但我找不到一种方法来保持dismissed屏幕上的图层。
上面的项目可以在这里找到
非常感谢。问候。