为什么我的 UIPageViewController 中的页面没有变化?
Why is the page not changing in my UIPageViewController?
我有一个 UIPageViewController 设置,其中包含我在故事板中创建的 5 个视图控制器。使用滑动手势可以很好地改变页面,但我希望在用户点击其中一个视图控制器中的按钮后页面发生变化。这是我的代码:
// PageVC.swift
import Foundation
import UIKit
class PageVC: UIPageViewController, UIPageViewControllerDataSource, UIPageViewControllerDelegate {
lazy var VCArr: [UIViewController] = {
return [self.VCInstance(name: "OB1"),
self.VCInstance(name: "OB2"),
self.VCInstance(name: "OB3"),
self.VCInstance(name: "OB4"),
self.VCInstance(name: "OB5"),
self.VCInstance(name: "OB6")]
}()
private func VCInstance(name: String) -> UIViewController {
return UIStoryboard(name: "Main", bundle: nil).instantiateViewController(withIdentifier: name)
}
override public func viewDidLoad() {
super.viewDidLoad()
self.dataSource = self
self.delegate = self
if let OB1 = VCArr.first {
setViewControllers([OB1], direction: .forward, animated: true, completion: nil)
}
}
public func pageViewController(_ pageViewController: UIPageViewController, viewControllerBefore viewController: UIViewController) -> UIViewController?{
guard let viewControllerIndex = VCArr.index(of: viewController) else {
return nil
}
let previousIndex = viewControllerIndex - 1
guard previousIndex >= 0 else {
return VCArr.last
}
guard VCArr.count > previousIndex else {
return nil
}
return VCArr[previousIndex]
}
public func pageViewController(_ pageViewController: UIPageViewController, viewControllerAfter viewController: UIViewController) -> UIViewController?{
guard let viewControllerIndex = VCArr.index(of: viewController) else {
return nil
}
let nextIndex = viewControllerIndex + 1
guard nextIndex < VCArr.count else {
return VCArr.first
}
guard VCArr.count > nextIndex else {
return nil
}
return VCArr[nextIndex]
}
public func presentationCount(for pageViewController: UIPageViewController) -> Int{
return VCArr.count
}
public func presentationIndex(for pageViewController: UIPageViewController) -> Int{
guard let OB1 = viewControllers?.first,
let OB1Index = VCArr.index(of: OB1) else {
return 0
}
return OB1Index
}
public func nextPageWithIndex(index: Int)
{
let nextVC = VCArr[index]
setViewControllers([nextVC], direction: .forward, animated: true, completion: nil)
}
}
我在我的一个视图控制器的 IBAction 中调用 nextPageWithIndex
方法:
// OB1.swift
import UIKit
class OB1: UIViewController {
@IBOutlet var getStartedColorChange: UIButton!
override func viewDidLoad() {
super.viewDidLoad()
}
@IBAction func getStartedBtn(_ sender: Any) {
let getStarted = PageVC()
getStarted.nextPageWithIndex(index: 2)
}
}
按钮有效,因为我可以从中打印,但页面没有变化。我需要更改什么才能使用按钮更改页面?
问题出在您的代码中 PageVC() 的新实例:
let getStarted = PageVC()
您必须获得对已创建的父控制器的引用!
@IBAction func getStartedBtn(_ sender: Any) {
let getStarted = self.parent as! PageVC
getStarted.nextPageWithIndex(index: 2)
}
我有一个 UIPageViewController 设置,其中包含我在故事板中创建的 5 个视图控制器。使用滑动手势可以很好地改变页面,但我希望在用户点击其中一个视图控制器中的按钮后页面发生变化。这是我的代码:
// PageVC.swift
import Foundation
import UIKit
class PageVC: UIPageViewController, UIPageViewControllerDataSource, UIPageViewControllerDelegate {
lazy var VCArr: [UIViewController] = {
return [self.VCInstance(name: "OB1"),
self.VCInstance(name: "OB2"),
self.VCInstance(name: "OB3"),
self.VCInstance(name: "OB4"),
self.VCInstance(name: "OB5"),
self.VCInstance(name: "OB6")]
}()
private func VCInstance(name: String) -> UIViewController {
return UIStoryboard(name: "Main", bundle: nil).instantiateViewController(withIdentifier: name)
}
override public func viewDidLoad() {
super.viewDidLoad()
self.dataSource = self
self.delegate = self
if let OB1 = VCArr.first {
setViewControllers([OB1], direction: .forward, animated: true, completion: nil)
}
}
public func pageViewController(_ pageViewController: UIPageViewController, viewControllerBefore viewController: UIViewController) -> UIViewController?{
guard let viewControllerIndex = VCArr.index(of: viewController) else {
return nil
}
let previousIndex = viewControllerIndex - 1
guard previousIndex >= 0 else {
return VCArr.last
}
guard VCArr.count > previousIndex else {
return nil
}
return VCArr[previousIndex]
}
public func pageViewController(_ pageViewController: UIPageViewController, viewControllerAfter viewController: UIViewController) -> UIViewController?{
guard let viewControllerIndex = VCArr.index(of: viewController) else {
return nil
}
let nextIndex = viewControllerIndex + 1
guard nextIndex < VCArr.count else {
return VCArr.first
}
guard VCArr.count > nextIndex else {
return nil
}
return VCArr[nextIndex]
}
public func presentationCount(for pageViewController: UIPageViewController) -> Int{
return VCArr.count
}
public func presentationIndex(for pageViewController: UIPageViewController) -> Int{
guard let OB1 = viewControllers?.first,
let OB1Index = VCArr.index(of: OB1) else {
return 0
}
return OB1Index
}
public func nextPageWithIndex(index: Int)
{
let nextVC = VCArr[index]
setViewControllers([nextVC], direction: .forward, animated: true, completion: nil)
}
}
我在我的一个视图控制器的 IBAction 中调用 nextPageWithIndex
方法:
// OB1.swift
import UIKit
class OB1: UIViewController {
@IBOutlet var getStartedColorChange: UIButton!
override func viewDidLoad() {
super.viewDidLoad()
}
@IBAction func getStartedBtn(_ sender: Any) {
let getStarted = PageVC()
getStarted.nextPageWithIndex(index: 2)
}
}
按钮有效,因为我可以从中打印,但页面没有变化。我需要更改什么才能使用按钮更改页面?
问题出在您的代码中 PageVC() 的新实例:
let getStarted = PageVC()
您必须获得对已创建的父控制器的引用!
@IBAction func getStartedBtn(_ sender: Any) {
let getStarted = self.parent as! PageVC
getStarted.nextPageWithIndex(index: 2)
}