UIPageViewController 设置限制页面
UIPageViewController set limit page
开始学习swift,使用UIPageViewController滑动第3页。我使用 class:
import Foundation
import UIKit
class MyPageViewController: UIPageViewController, UIPageViewControllerDataSource, UIPageViewControllerDelegate {
var pages = [UIViewController]()
var pageIndicator : UIPageControl!
override func viewDidLoad() {
super.viewDidLoad()
self.delegate = self
self.dataSource = self
let page1: UIViewController! = storyboard?.instantiateViewControllerWithIdentifier("page1")
let page2: UIViewController! = storyboard?.instantiateViewControllerWithIdentifier("page2")
let page3: UIViewController! = storyboard?.instantiateViewControllerWithIdentifier("page3")
pages.append(page1)
pages.append(page2)
pages.append(page3)
setViewControllers([page1], direction: UIPageViewControllerNavigationDirection.Forward, animated: false, completion: nil)
}
func viewControllerAtIndex(index: Int) -> UINavigationController! {
return nil
}
func pageViewController(pageViewController: UIPageViewController, viewControllerBeforeViewController viewController: UIViewController) -> UIViewController? {
let currentIndex = pages.indexOf(viewController)!
pageIndicator.currentPage = currentIndex
let previousIndex = abs((currentIndex - 1) % pages.count)
return pages[previousIndex]
}
func pageViewController(pageViewController: UIPageViewController, viewControllerAfterViewController viewController: UIViewController) -> UIViewController? {
let currentIndex = pages.indexOf(viewController)!
pageIndicator.currentPage = currentIndex
let nextIndex = abs((currentIndex + 1) % pages.count)
return pages[nextIndex]
}
func presentationCountForPageViewController(pageViewController: UIPageViewController) -> Int {
return pages.count
}
func presentationIndexForPageViewController(pageViewController: UIPageViewController) -> Int {
return 0
}
}
但是滑动到第三页没有停止,又从第一页开始。
如何限制前后滑动页面?
这是不同的解决方案。
您不需要拥有一整套复杂的代码来执行您需要的操作。
创建一个滚动视图。将其内容大小宽度设置为页数的倍数。
试试这个代码。这可能对您有帮助
override func viewDidLoad() {
super.viewDidLoad()
let screensize = UIScreen.mainScreen().bounds
pagescroll.frame = CGRectMake(0, 0,screensize.width, screensize.height)
pagescroll.contentSize = CGSize(width: screensize.width*3, height: screensize.height)
pagescroll.pagingEnabled = true
page1.frame = CGRectMake(0, 0, screensize.width, screensize.height)
page2.frame = CGRectMake(screensize.width, 0, screensize.width, screensize.height)
page3.frame = CGRectMake(screensize.width*2, 0, screensize.width, screensize.height)
pagescroll.addSubview(page1)
pagescroll.addSubview(page2)
pagescroll.addSubview(page2)
self.view.addSubview(pagescroll)
// Do any additional setup after loading the view.
}
var pagescroll = UIScrollView()
var page1 = UIView()
var page2 = UIView()
var page3 = UIView()
您还可以根据需要添加页面控制器:UIPageControl
我认为您在以下行中的索引计算有误。
`
let nextIndex = abs((currentIndex + 1) % pages.count)
return pages[nextIndex]`
最后一个视图控制器currentIndex=2,然后nextIndex=(2+1)%3=0。
所以你再次返回索引 0 处的视图控制器。
将以下行添加到您的方法中`
if(currentIndex == (pages.count-1))
{
return nil;
}
`注意:这是根据 objective c.
正如 UIBittu 已经指出的那样:您的计算需要修正。
可能的(可能更具可读性)解决方案可能如下所示:
func indexOfViewController(viewController: UIViewController) -> Int {
guard let index = pages.indexOf(viewController) else {
return NSNotFound
}
return index
}
func pageViewController(pageViewController: UIPageViewController, viewControllerBeforeViewController viewController: UIViewController) -> UIViewController? {
var index = indexOfViewController(viewController)
if (index == 0) || (index == NSNotFound) {
return nil
}
index--
return pages[index]
}
func pageViewController(pageViewController: UIPageViewController, viewControllerAfterViewController viewController: UIViewController) -> UIViewController? {
var index = indexOfViewController(viewController)
if (index == NSNotFound) || (index+1 == pages.count) {
return nil
}
index++
return pages[index]
}
开始学习swift,使用UIPageViewController滑动第3页。我使用 class:
import Foundation
import UIKit
class MyPageViewController: UIPageViewController, UIPageViewControllerDataSource, UIPageViewControllerDelegate {
var pages = [UIViewController]()
var pageIndicator : UIPageControl!
override func viewDidLoad() {
super.viewDidLoad()
self.delegate = self
self.dataSource = self
let page1: UIViewController! = storyboard?.instantiateViewControllerWithIdentifier("page1")
let page2: UIViewController! = storyboard?.instantiateViewControllerWithIdentifier("page2")
let page3: UIViewController! = storyboard?.instantiateViewControllerWithIdentifier("page3")
pages.append(page1)
pages.append(page2)
pages.append(page3)
setViewControllers([page1], direction: UIPageViewControllerNavigationDirection.Forward, animated: false, completion: nil)
}
func viewControllerAtIndex(index: Int) -> UINavigationController! {
return nil
}
func pageViewController(pageViewController: UIPageViewController, viewControllerBeforeViewController viewController: UIViewController) -> UIViewController? {
let currentIndex = pages.indexOf(viewController)!
pageIndicator.currentPage = currentIndex
let previousIndex = abs((currentIndex - 1) % pages.count)
return pages[previousIndex]
}
func pageViewController(pageViewController: UIPageViewController, viewControllerAfterViewController viewController: UIViewController) -> UIViewController? {
let currentIndex = pages.indexOf(viewController)!
pageIndicator.currentPage = currentIndex
let nextIndex = abs((currentIndex + 1) % pages.count)
return pages[nextIndex]
}
func presentationCountForPageViewController(pageViewController: UIPageViewController) -> Int {
return pages.count
}
func presentationIndexForPageViewController(pageViewController: UIPageViewController) -> Int {
return 0
}
}
但是滑动到第三页没有停止,又从第一页开始。 如何限制前后滑动页面?
这是不同的解决方案。 您不需要拥有一整套复杂的代码来执行您需要的操作。 创建一个滚动视图。将其内容大小宽度设置为页数的倍数。
试试这个代码。这可能对您有帮助
override func viewDidLoad() {
super.viewDidLoad()
let screensize = UIScreen.mainScreen().bounds
pagescroll.frame = CGRectMake(0, 0,screensize.width, screensize.height)
pagescroll.contentSize = CGSize(width: screensize.width*3, height: screensize.height)
pagescroll.pagingEnabled = true
page1.frame = CGRectMake(0, 0, screensize.width, screensize.height)
page2.frame = CGRectMake(screensize.width, 0, screensize.width, screensize.height)
page3.frame = CGRectMake(screensize.width*2, 0, screensize.width, screensize.height)
pagescroll.addSubview(page1)
pagescroll.addSubview(page2)
pagescroll.addSubview(page2)
self.view.addSubview(pagescroll)
// Do any additional setup after loading the view.
}
var pagescroll = UIScrollView()
var page1 = UIView()
var page2 = UIView()
var page3 = UIView()
您还可以根据需要添加页面控制器:UIPageControl
我认为您在以下行中的索引计算有误。 `
let nextIndex = abs((currentIndex + 1) % pages.count)
return pages[nextIndex]`
最后一个视图控制器currentIndex=2,然后nextIndex=(2+1)%3=0。 所以你再次返回索引 0 处的视图控制器。
将以下行添加到您的方法中`
if(currentIndex == (pages.count-1))
{
return nil;
}
`注意:这是根据 objective c.
正如 UIBittu 已经指出的那样:您的计算需要修正。
可能的(可能更具可读性)解决方案可能如下所示:
func indexOfViewController(viewController: UIViewController) -> Int {
guard let index = pages.indexOf(viewController) else {
return NSNotFound
}
return index
}
func pageViewController(pageViewController: UIPageViewController, viewControllerBeforeViewController viewController: UIViewController) -> UIViewController? {
var index = indexOfViewController(viewController)
if (index == 0) || (index == NSNotFound) {
return nil
}
index--
return pages[index]
}
func pageViewController(pageViewController: UIPageViewController, viewControllerAfterViewController viewController: UIViewController) -> UIViewController? {
var index = indexOfViewController(viewController)
if (index == NSNotFound) || (index+1 == pages.count) {
return nil
}
index++
return pages[index]
}