UIViewController 包含UIPageViewController ，后者包含UINavigationController ，后者又包含UIViewController。 我需要在最后一个视图控制器中添加一个滑动手势，但是滑动手势被处理得好像它们属于页面视图控制器一样。 我尝试通过编程和xib来实现此操作，但没有任何结果。UIPageViewController处理其手势之前，我无法实现我的目标。如何解决这个问题？protocol PageViewControllerElement: class {
var isLeftScrollEnabled: Bool { get }
var isRightScrollEnabled: Bool { get }
}
extension PageViewControllerElement {
// scroll is enabled in both directions by default
var isLeftScrollEnabled: Bool {
get {
return true
}
}
var isRightScrollEnabled: Bool {
get {
return true
}
}
}
extension SomeViewController: PageViewControllerElement {
var isRightScrollEnabled: Bool {
get {
return false
}
}
}
class SomeViewController: UIViewController {
// ...
}
第三步：
向您的 PVC 添加有效的滚动锁定方法：
class PVC: UIPageViewController, UIPageViewDelegate {
private var isLeftScrollEnabled = true
private var isRightScrollEnabled = true
// ...
override func viewDidLoad() {
super.viewDidLoad()
// ...
self.delegate = self
self.scrollView?.delegate = self
}
}
extension PVC: UIScrollViewDelegate {
func scrollViewDidScroll(_ scrollView: UIScrollView) {
print("contentOffset = \(scrollView.contentOffset.x)")
if !self.isLeftScrollEnabled {
disableLeftScroll(scrollView)
}
if !self.isRightScrollEnabled {
disableRightScroll(scrollView)
}
}
private func disableLeftScroll(_ scrollView: UIScrollView) {
let screenWidth = UIScreen.main.bounds.width
if scrollView.contentOffset.x < screenWidth {
scrollView.setContentOffset(CGPoint(x: screenWidth, y: 0), animated: false)
}
}
private func disableRightScroll(_ scrollView: UIScrollView) {
let screenWidth = UIScreen.main.bounds.width
if scrollView.contentOffset.x > screenWidth {
scrollView.setContentOffset(CGPoint(x: screenWidth, y: 0), animated: false)
}
}
}
extension UIPageViewController {
var scrollView: UIScrollView? {
return view.subviews.filter { $0 is UIScrollView }.first as? UIScrollView
}
}
步骤4：
当到达新屏幕时更新滚动相关属性（如果您手动转换到某个屏幕，请不要忘记调用enableScroll方法）：
func pageViewController(_ pageViewController: UIPageViewController, didFinishAnimating finished: Bool, previousViewControllers: [UIViewController], transitionCompleted completed: Bool) {
let pageContentViewController = pageViewController.viewControllers![0]
// ...
self.enableScroll(for: pageContentViewController)
}
private func enableScroll(for viewController: UIViewController) {
guard let viewController = viewController as? PageViewControllerElement else {
self.isLeftScrollEnabled = true
self.isRightScrollEnabled = true
return
}
self.isLeftScrollEnabled = viewController.isLeftScrollEnabled
self.isRightScrollEnabled = viewController.isRightScrollEnabled
if !self.isLeftScrollEnabled {
print("Left Scroll Disabled")
}
if !self.isRightScrollEnabled {
print("Right Scroll Disabled")
}
}
func removeSwipeGesture(){
for view in self.pageViewController!.view.subviews {
if let subView = view as? UIScrollView {
subView.isScrollEnabled = false
}
}
}
private let pageControl = PageControl()
pageControl.delegate = self
pageControl.numberOfPages = pages.count
pageControl.addTarget ....
pageControl.hidesForSinglePage = true
枚举子视图以查找UIPageViewController的scrollView对我没有用，因为我在我的页面控制器子类中找不到任何scrollView。所以我想到的是禁用手势识别器，但要小心不要禁用必要的手势。
所以我想到了这个：
if let panGesture = self.gestureRecognizers.filter({$0.isKind(of: UIPanGestureRecognizer.self)}).first
panGesture.isEnabled = false
}
viewDidLoad()中，一切都准备就绪！只需在您的UIPageViewController子类中添加此控件属性：
var isScrollEnabled = true {
didSet {
for case let scrollView as UIScrollView in view.subviews {
scrollView.isScrollEnabled = isScrollEnabled
}
}
}
override func viewDidLayoutSubviews() {
for View in self.view.subviews{
if View.isKind(of: UIScrollView.self){
let ScrollV = View as! UIScrollView
ScrollV.isScrollEnabled = false
}
}
}
将以下代码添加到您的PageViewController类中。百分之百有效。
pageViewControllerObject.view.userInteractionEnabled = NO;，将页面视图控制器对象的用户交互功能设置为禁用。 - SrikanthUIPageViewController中的一个页面包含UINavigationController。客户希望在滑动手势时弹出导航控制器（如果可能的话），但是页面视图控制器处理滑动手势。 - user2159978