我正在遵循本教程:http://swiftiostutorials.com/ios-tutorial-using-uipageviewcontroller-create-content-slider-objective-cswift/创建一个显示多个滑块的应用程序。
即使我已使本教程正常工作,此示例也仅根据存储在数组中的图像更改图像。
如何获取它来加载ViewController而不是图像
我有4个ViewController:
我希望一张幻灯片显示ViewController1,而slide2加载ViewController2等...。
这是我的主要ViewController:
import UIKit
class ViewController: UIViewController, UIPageViewControllerDataSource {
// MARK: - Variables
private var pageViewController: UIPageViewController?
// Initialize it right away here
private let contentImages = ["nature_pic_1.png",
"nature_pic_2.png",
"nature_pic_3.png",
"nature_pic_4.png"];
// MARK: - View Lifecycle
override func viewDidLoad() {
super.viewDidLoad()
createPageViewController()
setupPageControl()
}
private func createPageViewController() {
let pageController = self.storyboard!.instantiateViewControllerWithIdentifier("PageController") as UIPageViewController
pageController.dataSource = self
if contentImages.count > 0 {
let firstController = getItemController(0)!
let startingViewControllers: NSArray = [firstController]
pageController.setViewControllers(startingViewControllers, direction: UIPageViewControllerNavigationDirection.Forward, animated: false, completion: nil)
}
pageViewController = pageController
addChildViewController(pageViewController!)
self.view.addSubview(pageViewController!.view)
pageViewController!.didMoveToParentViewController(self)
}
private func setupPageControl() {
let appearance = UIPageControl.appearance()
appearance.pageIndicatorTintColor = UIColor.grayColor()
appearance.currentPageIndicatorTintColor = UIColor.whiteColor()
appearance.backgroundColor = UIColor.darkGrayColor()
}
// MARK: - UIPageViewControllerDataSource
func pageViewController(pageViewController: UIPageViewController, viewControllerBeforeViewController viewController: UIViewController) -> UIViewController? {
let itemController = viewController as PageItemController
if itemController.itemIndex > 0 {
return getItemController(itemController.itemIndex-1)
}
return nil
}
func pageViewController(pageViewController: UIPageViewController, viewControllerAfterViewController viewController: UIViewController) -> UIViewController? {
let itemController = viewController as PageItemController
if itemController.itemIndex+1 < contentImages.count {
return getItemController(itemController.itemIndex+1)
}
return nil
}
private func getItemController(itemIndex: Int) -> PageItemController? {
if itemIndex < contentImages.count {
let pageItemController = self.storyboard!.instantiateViewControllerWithIdentifier("ItemController") as PageItemController
pageItemController.itemIndex = itemIndex
pageItemController.imageName = contentImages[itemIndex]
return pageItemController
}
return nil
}
// MARK: - Page Indicator
func presentationCountForPageViewController(pageViewController: UIPageViewController) -> Int {
return contentImages.count
}
func presentationIndexForPageViewController(pageViewController: UIPageViewController) -> Int {
return 0
}
这是我的PageItemController:
import UIKit
class PageItemController: UIViewController {
// MARK: - Variables
var itemIndex: Int = 0
var imageName: String = "" {
didSet {
if let imageView = contentImageView {
imageView.image = UIImage(named: imageName)
}
}
}
@IBOutlet var contentImageView: UIImageView?
// MARK: - View Lifecycle
override func viewDidLoad() {
super.viewDidLoad()
contentImageView!.image = UIImage(named: imageName)
}
}
我是Swift/iOS开发的新手,我真的想通过开发来了解它。预先感谢您的回答:)
编辑:清除问题
我如何做到这一点,以便有一个与UIPageViewController的左/右幻灯片相对应的 View Controller 数组?
因此,当我在ViewController1上向左滑动时-将加载UIViewController2并向右滑动。
最佳答案
假设您已在与UIPageViewController相同的 Storyboard 中定义了 View Controller 1-4,并且将其 Storyboard ID设置为ViewController0,ViewController1等,然后创建一种方法来填充 View Controller 数组并在viewDidLoad()
中对其进行调用调用createPageViewController()
override func viewDidLoad() {
super.viewDidLoad()
populateControllersArray()
createPageViewController()
setupPageControl()
}
像这样实现方法:
var controllers = [PageItemController]()
func populateControllersArray() {
for i in 0...3 {
let controller = storyboard!.instantiateViewControllerWithIdentifier("ViewController\(i)") as PageItemController
controller.itemIndex = i
controllers.append(controller)
}
}
并将您的
createPageViewController()
定义为以下内容 private func createPageViewController() {
let pageController = self.storyboard!.instantiateViewControllerWithIdentifier("PageController") as UIPageViewController
pageController.dataSource = self
if !controllers.isEmpty {
pageController.setViewControllers([controllers[0]], direction: UIPageViewControllerNavigationDirection.Forward, animated: false, completion: nil)
}
pageViewController = pageController
addChildViewController(pageViewController!)
self.view.addSubview(pageViewController!.view)
pageViewController!.didMoveToParentViewController(self)
}
然后在您的两个委托(delegate)之前和之后的方法中:
func pageViewController(pageViewController: UIPageViewController, viewControllerBeforeViewController viewController: UIViewController) -> UIViewController? {
if let controller = viewController as? PageItemController {
if controller.itemIndex > 0 {
return controllers[controller.itemIndex - 1]
}
}
return nil
}
func pageViewController(pageViewController: UIPageViewController, viewControllerAfterViewController viewController: UIViewController) -> UIViewController? {
if let controller = viewController as? PageItemController {
if controller.itemIndex < controllers.count - 1 {
return controllers[controller.itemIndex + 1]
}
}
return nil
}
并在计数方法中
func presentationCountForPageViewController(pageViewController: UIPageViewController) -> Int {
return controllers.count
}
实际上,您可以使用要显示的任何 View Controller 填充
controllers
,只需将其类设置为 Storyboard 中的PageItemController(以具有index属性)即可。或者,您可以将每个 View Controller 设置为自己的类,并使用运行时属性获取和设置。
在before和after方法中使用
controller.valueForKey("itemIndex") as Int
而不是controller.itemIndex
使用
controller.setValue(i, forKey: "itemIndex")
代替controller.itemIndex = i
中的populateControllersArray()
。只需确保每个 Controller 类都具有
Int
属性itemIndex
,否则您的应用程序将崩溃。要将所有内容整合到您的代码中,请执行以下操作:
import UIKit
import UIKit
class ViewController: UIViewController, UIPageViewControllerDataSource {
// MARK: - Variables
private var pageViewController: UIPageViewController?
// MARK: - View Lifecycle
override func viewDidLoad() {
super.viewDidLoad()
populateControllersArray()
createPageViewController()
setupPageControl()
}
var controllers = [PageItemController]()
func populateControllersArray() {
for i in 0...3 {
let controller = storyboard!.instantiateViewControllerWithIdentifier("ViewController\(i)") as PageItemController
controller.itemIndex = i
controllers.append(controller)
}
}
private func createPageViewController() {
let pageController = self.storyboard!.instantiateViewControllerWithIdentifier("PageController") as UIPageViewController
pageController.dataSource = self
if !controllers.isEmpty {
pageController.setViewControllers([controllers[0]], direction: UIPageViewControllerNavigationDirection.Forward, animated: false, completion: nil)
}
pageViewController = pageController
addChildViewController(pageViewController!)
self.view.addSubview(pageViewController!.view)
pageViewController!.didMoveToParentViewController(self)
}
private func setupPageControl() {
let appearance = UIPageControl.appearance()
appearance.pageIndicatorTintColor = UIColor.grayColor()
appearance.currentPageIndicatorTintColor = UIColor.whiteColor()
appearance.backgroundColor = UIColor.darkGrayColor()
}
// MARK: - UIPageViewControllerDataSource
func pageViewController(pageViewController: UIPageViewController, viewControllerBeforeViewController viewController: UIViewController) -> UIViewController? {
if let controller = viewController as? PageItemController {
if controller.itemIndex > 0 {
return controllers[controller.itemIndex - 1]
}
}
return nil
}
func pageViewController(pageViewController: UIPageViewController, viewControllerAfterViewController viewController: UIViewController) -> UIViewController? {
if let controller = viewController as? PageItemController {
if controller.itemIndex < controllers.count - 1 {
return controllers[controller.itemIndex + 1]
}
}
return nil
}
// MARK: - Page Indicator
func presentationCountForPageViewController(pageViewController: UIPageViewController) -> Int {
return controllers.count
}
func presentationIndexForPageViewController(pageViewController: UIPageViewController) -> Int {
return 0
}