Swift uses CollectionView to implement picture Carousel encapsulation that's simple

Preface: This article you can learn custom view, create CollectionView, use of protocol, timer;

Homemade pictures

First on the Demo:github on the package good download is ready to use, please star Thanks
First create a new view that inherits from UIView, and it is implemented with CollectionView, so we need to sign two protocol codes as follows:

let sectionnum:  Int = 100 //area number let width = uiscreen.mainscreen (). Bounds.size.width //screen width let height = uiscreen.mainscreen (). Bounds.size.width //screen height //because to implement a carousel picture you can click Define a protocol //protocol protocol xtcycleviewdelegate {func didselectindexcollectionviewcell (index:int)->void}        

UIView, UICollectionViewDelegate, UICollectionViewDataSource{

Variables to use and create views

    var delegate:Xtcycleviewdelegate?var Cyclecollectionview: uicollectionview? var images = nsmutablearray () var Pagecontrol = uipagecontrol () var flowlayout = uicollectionviewflowlayout () var timer = NSTimer () Span class= "Hljs-keyword" >override init (frame: CGRect) {super. init (frame:frame) self.createsubviews (frame)} required Span class= "Hljs-keyword" >init? (Coder Adecoder: nscoder) {fatalerror ( "Init (coder:) have not been Implemented ")}               

Layout the necessary UI and create timers

Func Createsubviews (frame:CGRect) {Cyclecollectionview =Uicollectionview. Init (frame:CGRectMake (0,0, Frame. Size. width, Frame. Size. height), collectionviewlayout:flowlayout) FlowLayout. itemsize =Cgsizemake (frame. Size. width, Frame. Size. height); FlowLayout. minimuminteritemspacing =0; FlowLayout. minimumlinespacing =0; FlowLayout. scrolldirection =Uicollectionviewscrolldirection. Horizontal; cyclecollectionview!. BackgroundColor =Uicolor. Lightgraycolor () cyclecollectionview!. pagingenabled =True cyclecollectionview!. DataSource =Self cyclecollectionview!. Delegate =Self cyclecollectionview!. Showshorizontalscrollindicator =False cyclecollectionview!. Showsverticalscrollindicator =False cyclecollectionview!. registerclass (Zjcustomcyclecell. Self, Forcellwithreuseidentifier:"Cellid")Self. Addsubview (cyclecollectionview!) Pagecontrol =Uipagecontrol. Init (frame: CGRectMake (0, 0, frame. Size. Width/ 2, )) Pagecontrol . Center = Cgpointmake (frame. Size. Width/ 2, Frame. Size. Height- 20); self. Addsubview (Pagecontrol); Self . AddTimer ()}                

Timer initialization

func addTimer(){        let timer1 = NSTimer.init(timeInterval: 2, target: self, selector: "nextPageView", userInfo: nil, repeats: true) NSRunLoop.currentRunLoop().addTimer(timer1, forMode: NSRunLoopCommonModes) timer = timer1 }

Destroying timers

func removeTimer(){        self.timer.invalidate() }

Implementing circular Scrolling

 FuncReturnindexpath()nsindexpath{var Currentindexpath = cyclecollectionview!. Indexpathsforvisibleitems (). Last Currentindexpath =Nsindexpath.Init (forrow: (Currentindexpath?. Row)!, Insection:sectionnum/2) cyclecollectionview!. Scrolltoitematindexpath (currentindexpath!, Atscrollposition:Uicollectionviewscrollposition.Left, animated:Falsereturn currentindexpath!; }Funcnextpageview () {let IndexPath = Span class= "Hljs-keyword" >self.returnindexpath () var item = indexpath.row + 1; var section = indexpath.section; if item = = images. count {item = 0 section++}  Self.pageControl.currentPage = Item; let Nextindexpath = nsindexpath. Init (Forrow:item, insection:section) cyclecollectionview!. Scrolltoitematindexpath (Nextindexpath, atscrollposition: uicollectionviewscrollposition. left, Animated: true)}       

CollectionView Delegate

     Reusing poolsFuncCollectionView(Collectionview:uicollectionview, Cellforitematindexpath Indexpath:nsindexpath)Uicollectionviewcell {The custom cell that is used here will be labeled with the custom cell codeLet cell = Collectionview.dequeuereusablecellwithreuseidentifier ("Cellid", Forindexpath:indexpath)as!ZjcustomcyclecellThis label implements the display number, which represents the first few pictures cell.labelTitle.text =NSString (format:"%d", Indexpath.row)AsStringHere is the picture assignmentLet URL:String =Self.images[indexpath.row]as!StringHere I am using an assignment picture of the three-party library, to see their preferences, for the convenience I did not write their own cell.imageView.hnk_setImageFromURL (nsurl. init (string:url)!) return Cell} func  Numberofsectionsincollectionview (Collectionview:uicollectionview), int {return sectionnum}  Func collectionview (Collectionview:uicollectionview, Numberofitemsinsection section:int), int {// The number of Pagecontrol is given here pagecontrol.numberofpages = images. count return images. Count}                

    //  重新添加定时器    func scrollViewDidEndDragging(scrollView: UIScrollView, willDecelerate decelerate: Bool) { self.addTimer() } // 手动滑动的时候销毁定时器 func scrollViewWillBeginDragging(scrollView: UIScrollView) { self.removeTimer() }

Set the current Pagecontrol

func scrollViewDidEndDecelerating(scrollView: UIScrollView) {        let page = (Int(scrollView.contentOffset.x) / Int(width)) % images.count pageControl.currentPage = page }

click Method

func collectionView(collectionView: UICollectionView, didSelectItemAtIndexPath indexPath: NSIndexPath) {        self.delegate?.didSelectIndexCollectionViewCell(indexPath.row) }

Here's my code in the custom cell

    var urlimage:String =""var ImageView =Uiimageview ()var labeltitle =UILabel ()OverrideInit (frame:CGRect) {Super.Init (Frame:frame)Self.createsubviews (frame)} requiredinit? (Coder Adecoder: nscoder) {fatalerror ( "Init (coder:) have not been Implemented ")} func createSubviews< Span class= "Hljs-params" > (frame:cgrect) {ImageView = uiimageview. Init (frame: cgrectmake (0, 0, Frame.size.width, Frame.size.height)) self.contentview.addsubview (ImageView) Labeltitle = uilabel. Init (frame: cgrectmake (10, 10, 30, 30)) Imageview.addsubview (Labeltitle)}      

The package is basically done, so let's see how to use

        // 创建        let cycle = XTCycleScrollView.init(frame: CGRectMake(0, 70, width, 175)) // 要实现点击需要制定代理人 cycle.delegate = self; // 图片链接数组 let images: NSMutableArray = ["", "", "", ""] // 数组赋值 cycle.images = images self.view.addSubview(cycle)

Implementing Proxy methods

func didSelectIndexCollectionViewCell(index: Int) {        print("\\(index)") }

Summary: This will achieve a simple picture carousel effect, and with a click Method, you can see here on the point of praise it. Ha ha

Wen/summer Then (Jane book author)
Original link: http://www.jianshu.com/p/f5fa66699a96
Copyright belongs to the author, please contact the author to obtain authorization, and Mark "book author".

Swift uses CollectionView to implement picture Carousel encapsulation that's simple