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I would like to provide an example how to do a horizontal page scrolling usingUICollectionView.

Please set upisPaggingEnabled property toYES for the collection view object. Or viaInterface Builder:

And let’s create a custom class for the flow layout:

Please use the following code:

import UIKitclass CenterViewFlowLayout: UICollectionViewFlowLayout {override func collectionViewContentSize() -> CGSize {// Only support single section for now.// Only support Horizontal scrolllet count = self.collectionView?.dataSource?.collectionView(self.collectionView!, numberOfItemsInSection: 0)let canvasSize = self.collectionView!.frame.sizevar contentSize = canvasSizeif self.scrollDirection == UICollectionViewScrollDirection.Horizontal {let rowCount = Int((canvasSize.height - self.itemSize.height) / (self.itemSize.height + self.minimumInteritemSpacing) + 1)let columnCount = Int((canvasSize.width - self.itemSize.width) / (self.itemSize.width + self.minimumLineSpacing) + 1)let page = ceilf(Float(count!) / Float(rowCount * columnCount))contentSize.width = CGFloat(page) * canvasSize.width}return contentSize}func frameForItemAtIndexPath(indexPath: NSIndexPath) -> CGRect {let canvasSize = self.collectionView!.frame.sizelet rowCount = Int((canvasSize.height - self.itemSize.height) / (self.itemSize.height + self.minimumInteritemSpacing) + 1)let columnCount = Int((canvasSize.width - self.itemSize.width) / (self.itemSize.width + self.minimumLineSpacing) + 1)let pageMarginX = (canvasSize.width - CGFloat(columnCount) * self.itemSize.width - (columnCount > 1 ? CGFloat(columnCount - 1) * self.minimumLineSpacing : 0)) / 2.0let pageMarginY = (canvasSize.height - CGFloat(rowCount) * self.itemSize.height - (rowCount > 1 ? CGFloat(rowCount - 1) * self.minimumInteritemSpacing : 0)) / 2.0let page = Int(CGFloat(indexPath.row) / CGFloat(rowCount * columnCount))let remainder = Int(CGFloat(indexPath.row) - CGFloat(page) * CGFloat(rowCount * columnCount))let row = Int(CGFloat(remainder) / CGFloat(columnCount))let column = Int(CGFloat(remainder) - CGFloat(row) * CGFloat(columnCount))var cellFrame = CGRectZerocellFrame.origin.x = pageMarginX + CGFloat(column) * (self.itemSize.width + self.minimumLineSpacing)cellFrame.origin.y = pageMarginY + CGFloat(row) * (self.itemSize.height + self.minimumInteritemSpacing)cellFrame.size.width = self.itemSize.widthcellFrame.size.height = self.itemSize.heightif self.scrollDirection == UICollectionViewScrollDirection.Horizontal {cellFrame.origin.x += CGFloat(page) * canvasSize.width}return cellFrame}override func layoutAttributesForItemAtIndexPath(indexPath: NSIndexPath) -> UICollectionViewLayoutAttributes? {let attr = super.layoutAttributesForItemAtIndexPath(indexPath)?.copy() as! UICollectionViewLayoutAttributes?attr!.frame = self.frameForItemAtIndexPath(indexPath)return attr}override func layoutAttributesForElementsInRect(rect: CGRect) -> [UICollectionViewLayoutAttributes]? {let originAttrs = super.layoutAttributesForElementsInRect(rect)var attrs: [UICollectionViewLayoutAttributes]? = Array()for attr in originAttrs! {let idxPath = attr.indexPathlet itemFrame = self.frameForItemAtIndexPath(idxPath)if CGRectIntersectsRect(itemFrame, rect) {let nAttr = self.layoutAttributesForItemAtIndexPath(idxPath)attrs?.append(nAttr!)}}return attrs}}