一、小叙
UIPageViewController是一个实现图书阅读的控制器,使用它可以设置书脊位置、单双页、过渡效果等,它是通过代理的方式来实现翻页,也即上一页、下一页。最终这个UIPageViewController被包装后添加到当前控制器即可。
二、直接上代码
//
// ViewController.swift
// PageViewControllerDemo
//
// Created by 夏远全 on 2017/1/19.
// Copyright © 2017年 夏远全. All rights reserved.
//
import UIKit
class ViewController: UIViewController,UIPageViewControllerDelegate,UIPageViewControllerDataSource {
//定义UIPageViewController和内容数组
var pageController:UIPageViewController!
var pageContent:[String] = [String]()
override func viewDidLoad() {
super.viewDidLoad()
//初始化UIPageViewController
//transitionStyle: 翻页效果(卷起来翻卷、水平活动翻卷)
//navigationOrientation:翻页方向(水平方向、竖直方向)
//options: 这是一个字典,设置翻页控制器的书脊位置(none/min/mid/max)
pageController = UIPageViewController.init(transitionStyle: .pageCurl, navigationOrientation: .horizontal, options: [UIPageViewControllerOptionSpineLocationKey:NSNumber(value:UIPageViewControllerSpineLocation.min.rawValue)])
pageController.view.frame = self.view.bounds
//设置代理,提供展示相关的信息和接收手势发起的转换的通知
pageController.delegate = self
//设置数据源,提供展示的内容
pageController.dataSource = self
//创建显示内容
self.createContentPages()
//初始化内容控制器
let initalViewController = self.viewControllerAtIndex(index: 0)
pageController.setViewControllers([initalViewController!], direction: .forward, animated: false) { (b:Bool) in
//UIPageController必须放在Controller Container中
self.addChildViewController(self.pageController)
self.view.addSubview(self.pageController.view)
self.pageController.didMove(toParentViewController: self)
}
}
//自定义方法,创建显示视图
func viewControllerAtIndex(index:Int) -> ContentViewController? {
if self.pageContent.count == 0 || index > self.pageContent.count {
return nil
}
let dataViewController = ContentViewController()
dataViewController.dataObject = self.pageContent[index]
dataViewController.loadHTMLContent()
return dataViewController
}
//自定义方法,获取viewController的页码
func indexOfViewController(viewControler:ContentViewController) -> Int {
return self.pageContent.index(of: viewControler.dataObject!)!
}
//自定义方法,创建显示内容
func createContentPages() -> Void {
for i in 1..<11 {
let contentString = "<html><head></head><body><h1>《侠客行》</h1><p>第\(i)页</p></body></html>"
pageContent.append(contentString)
}
}
//实现UIPageViewControllerDeleagte代理方法
//将要翻页
func pageViewController(_ pageViewController: UIPageViewController, willTransitionTo pendingViewControllers: [UIViewController]) {
print("started")
}
//翻页结束
func pageViewController(_ pageViewController: UIPageViewController, didFinishAnimating finished: Bool, previousViewControllers: [UIViewController], transitionCompleted completed: Bool) {
print("finished")
}
//设置书脊位置
func pageViewController(_ pageViewController: UIPageViewController, spineLocationFor orientation: UIInterfaceOrientation) -> UIPageViewControllerSpineLocation {
return .min
}
//设置设备支持方向
func pageViewControllerSupportedInterfaceOrientations(_ pageViewController: UIPageViewController) -> UIInterfaceOrientationMask {
return .all
}
//设置优选方向
func pageViewControllerPreferredInterfaceOrientationForPresentation(_ pageViewController: UIPageViewController) -> UIInterfaceOrientation {
return .portrait
}
//实现UIPageViewControllerDataSource数据源方法
//返回总页数
func presentationCount(for pageViewController: UIPageViewController) -> Int {
return self.pageContent.count
}
//向前翻页
func pageViewController(_ pageViewController: UIPageViewController, viewControllerBefore viewController: UIViewController) -> UIViewController? {
//获取当前viewController的页码
var index:Int = self.indexOfViewController(viewControler: viewController as! ContentViewController)
//如果是第0页,返回nil
if index == 0 || (index == NSNotFound) {
return nil
}
index -= 1
return self.viewControllerAtIndex(index: index)
}
//向后翻页
func pageViewController(_ pageViewController: UIPageViewController, viewControllerAfter viewController: UIViewController) -> UIViewController? {
//获取当前viewController的页码
var index:Int = self.indexOfViewController(viewControler: viewController as! ContentViewController)
if index == NSNotFound {
return nil
}
index += 1
//如果是最后一张,返回nil
if index == self.pageContent.count {
return nil
}
return self.viewControllerAtIndex(index: index)
}
}
三、效果(点击屏幕实现翻页)
程序猿神奇的手,每时每刻,这双手都在改变着世界的交互方式!