import UIKit

 class ViewController: UIViewController,UICollectionViewDelegate,UICollectionViewDataSource {

     var myCollectionView: UICollectionView!

     override func viewDidLoad() {

         super.viewDidLoad()

         // Do any additional setup after loading the view, typically from a nib.

         view.backgroundColor = UIColor(red: /255.0, green: /255.0, blue: /255.0, alpha: 1.0)

         setupCollectionView()

     }

     // set up collection view

     private func setupCollectionView() {

         let screenW = UIScreen.mainScreen().bounds.size.width;

         var rect = view.bounds

         rect.size.height = (screenW -  *  -  * ) /  +  +

         rect.origin.y =

         myCollectionView = UICollectionView(frame: rect, collectionViewLayout: collectionLayout())

         myCollectionView.backgroundColor = UIColor.whiteColor()

         myCollectionView.pagingEnabled = true

         myCollectionView.showsHorizontalScrollIndicator = true

         myCollectionView.delegate = self

         myCollectionView.dataSource = self

         view.addSubview(myCollectionView)

       myCollectionView.registerClass(CollectionViewCell.self, forCellWithReuseIdentifier: "CollectionViewCell")

     }

     // set up layout

     private func collectionLayout() -> UICollectionViewLayout {

         let layout = CustomLayout()

         return layout;

     }

     //MARK:- collection view data source

     func numberOfSectionsInCollectionView(collectionView: UICollectionView) -> Int {

         return

     }

     func collectionView(collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {

         return

     }

     func collectionView(collectionView: UICollectionView, cellForItemAtIndexPath indexPath: NSIndexPath) -> UICollectionViewCell {

         let cell: UICollectionViewCell = collectionView.dequeueReusableCellWithReuseIdentifier("CollectionViewCell", forIndexPath: indexPath)

         return cell

     }

     func collectionView(collectionView: UICollectionView, didSelectItemAtIndexPath indexPath: NSIndexPath) {

         print(indexPath.row)

     }

 }

 import UIKit

 let edgeMargin: CGFloat =    // 边界的间距

 let padding: CGFloat =      // 内部每个cell的间距

 let column: Int =       // 每页有多少列

 let row: Int =         // 每页有多少行

 class CustomLayout: UICollectionViewLayout {

     private var layoutAttr: [UICollectionViewLayoutAttributes] = []

     var totalCount: Int {  // 有多少cell

         get {

             return collectionView!.numberOfItemsInSection()

         }

     }

     var page: Int {

         get {

             let numOfPage: Int = column * row

             return totalCount / numOfPage +

         }

     }

     // 重写此方法，自定义想要的布局

     override func prepareLayout() {

         super.prepareLayout()

         // 这个方法最主要的任务是计算出每个cell的位置

         layoutAttr = []

         var indexPath: NSIndexPath

         for index in ..<totalCount {

             indexPath = NSIndexPath(forRow: index, inSection: )

             let attributes = layoutAttributesForItemAtIndexPath(indexPath)!

             layoutAttr.append(attributes)

         }

     }

     override func collectionViewContentSize() -> CGSize { // 返回滚动的Size，根据页数计算出来

         return CGSizeMake(collectionView!.frame.size.width * CGFloat(page), collectionView!.frame.size.height)

     }

     override func shouldInvalidateLayoutForBoundsChange(newBounds: CGRect) -> Bool {

         return true

     }

     override func layoutAttributesForItemAtIndexPath(indexPath: NSIndexPath) -> UICollectionViewLayoutAttributes? {

         // 这个方法用来计算每一个cell的位置

         let att: UICollectionViewLayoutAttributes = UICollectionViewLayoutAttributes(forCellWithIndexPath: indexPath)

         let collectW: CGFloat = collectionView!.frame.size.width   // collection view 宽度

         let numOfPage: Int = column * row

         let pageIndex: Int = indexPath.row / numOfPage    // 当前cell处在哪一个页

         let columnInPage: Int = indexPath.row % numOfPage % column   // 当前cell 在当前页的哪一列，用来计算位置

         let rowInPage: Int = indexPath.row % numOfPage / column  // 当前cell 在当前页的哪一行，用来计算位置

         // 计算宽度

         let cellW: CGFloat = (collectW - edgeMargin *  - CGFloat(column - ) * padding) / CGFloat(column)

         // 高度

         let cellH: CGFloat = cellW

         // x

         let cellX: CGFloat = collectW * CGFloat(pageIndex) + edgeMargin + (cellW + padding) * CGFloat(columnInPage)

         // y

         let cellY :CGFloat = edgeMargin + (cellH + padding) * CGFloat(rowInPage)

         att.frame = CGRectMake(cellX, cellY, cellW, cellH)

         return att

     }

     override func layoutAttributesForElementsInRect(rect: CGRect) -> [UICollectionViewLayoutAttributes]? {

         return layoutAttr

     }

 }