iOS开发笔记（Swift）－通用App安装引导页的实现

之前一直做的项目都是基于OC开发的，最近开始尝试使用Swift语言来重写整个项目。

本篇文章主要是讲述如何使用Swift来实现常见的通用App安装引导界面。

效果预览：

实现思路：

主要是采用了UIScrollView作为容器，将其ContentSize的宽度设置为（引导页数量）＊屏幕宽度，并将pagingEnabled设为true，隐藏滚动条。作为指示的UIPageControl与UIScrollView直接添加到self.view之上，并保存UiPageControl居于最上。

实现代码：

import UIKit

class YSYGuideViewController: UIViewController,UIScrollViewDelegate {
    var scrollView:UIScrollView!
    var pageControl:UIPageControl!
    var startBtn:UIButton!

    override func viewDidLoad() {
        super.viewDidLoad()

        // Do any additional setup after loading the view.
        loadCustomLayout()

    }

    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
    }

    //scrollview委托
    func scrollViewDidScroll(scrollView: UIScrollView) {
        var offset=scrollView.contentOffset
        pageControl.currentPage=Int(offset.x/Yunshouyi.SCREEN_WIDTH)
        if(pageControl.currentPage==2){
            startBtn.hidden=false
        }else{
            startBtn.hidden=true
        }
    }

    //载入自定义布局
    func loadCustomLayout(){
        scrollView=UIScrollView(frame: CGRectMake(0, 0, Yunshouyi.SCREEN_WIDTH, Yunshouyi.SCREEN_HEIGHT))
        scrollView.pagingEnabled=true
        scrollView.showsHorizontalScrollIndicator=false
        scrollView.showsVerticalScrollIndicator=false
        scrollView.contentSize=CGSizeMake(3*Yunshouyi.SCREEN_WIDTH, Yunshouyi.SCREEN_HEIGHT)
        for i in 1...4{
            var image=UIImage(named: "Guideline-\(i)")
            var imageView=UIImageView(image: image)
            imageView.frame=CGRectMake(CGFloat((i-1))*Yunshouyi.SCREEN_WIDTH, 0, Yunshouyi.SCREEN_WIDTH, Yunshouyi.SCREEN_HEIGHT)
            imageView.contentMode = UIViewContentMode.ScaleToFill
            scrollView.addSubview(imageView)

        }
        pageControl=UIPageControl(frame: CGRectMake(Yunshouyi.SCREEN_WIDTH/2-100, Yunshouyi.SCREEN_HEIGHT-100, 200, 100))
        startBtn=UIButton(frame: CGRectMake(Yunshouyi.SCREEN_WIDTH/2-60, Yunshouyi.SCREEN_HEIGHT/2+50, 120, 35))

        pageControl.numberOfPages=3;
        pageControl.currentPage=0

        startBtn.setTitle("马上体验", forState: UIControlState.Normal)
        startBtn.setBackgroundImage(UIImage(named: "StartButton"), forState: UIControlState.Normal)
        startBtn.setTitleColor(UIColor.whiteColor(), forState: UIControlState.Normal)
        startBtn.addTarget(self, action: "guideOver", forControlEvents: UIControlEvents.TouchUpInside)
        startBtn.hidden=true

        scrollView.bounces=false
        scrollView.delegate=self
        self.view.addSubview(scrollView)
        self.view.addSubview(pageControl)
        self.view.addSubview(startBtn)

    }

    //开始使用app
    func guideOver(){
        var mainVC=UINavigationController(rootViewController: UITableViewController())
        self.presentViewController(mainVC, animated: true, completion: nil)

    }

    override func prefersStatusBarHidden() -> Bool {
     return true
    }

}