https://github.com/maximbilan/uicollectionviewhorizontalpaging

iOS UICollectionView Page Scrolling
https://github.com/maximbilan/uicollectionviewhorizontalpaging

horizontal ios ios-app paging swift uicollectionview

Last synced: about 1 month ago
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iOS UICollectionView Page Scrolling

• Host: GitHub
• URL: https://github.com/maximbilan/uicollectionviewhorizontalpaging
• Owner: maximbilan
• License: mit
• Created: 2016-02-05T08:30:06.000Z (over 9 years ago)
• Default Branch: master
• Last Pushed: 2018-09-22T09:37:12.000Z (over 6 years ago)
• Last Synced: 2025-03-27T20:44:22.356Z (about 2 months ago)
• Topics: horizontal, ios, ios-app, paging, swift, uicollectionview
• Language: Swift
• Homepage:
• Size: 1.58 MB
• Stars: 73
• Watchers: 4
• Forks: 12
• Open Issues: 1
• Metadata Files:
  • Readme: README.md
  • License: LICENSE

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README

        
# iOS UICollectionView Page Scrolling

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

![alt tag](https://raw.github.com/maximbilan/UICollectionViewHorizontalPaging/master/img/1.gif)

Please set up isPaggingEnabled property to YES for the collection view object. Or via Interface Builder:

![alt tag](https://raw.github.com/maximbilan/UICollectionViewHorizontalPaging/master/img/2.png)

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

![alt tag](https://raw.github.com/maximbilan/UICollectionViewHorizontalPaging/master/img/3.png)

Please use the following code:


import UIKit


class CenterViewFlowLayout: UICollectionViewFlowLayout {

	

	override func collectionViewContentSize() -> CGSize {

		// Only support single section for now.

		// Only support Horizontal scroll

		let count = self.collectionView?.dataSource?.collectionView(self.collectionView!, numberOfItemsInSection: 0)

		let canvasSize = self.collectionView!.frame.size

		var contentSize = canvasSize

		if 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.size

		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 pageMarginX = (canvasSize.width - CGFloat(columnCount) * self.itemSize.width - (columnCount > 1 ? CGFloat(columnCount - 1) * self.minimumLineSpacing : 0)) / 2.0

		let pageMarginY = (canvasSize.height - CGFloat(rowCount) * self.itemSize.height - (rowCount > 1 ? CGFloat(rowCount - 1) * self.minimumInteritemSpacing : 0)) / 2.0

		

		let 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 = CGRectZero

		cellFrame.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.width

		cellFrame.size.height = self.itemSize.height

		

		if 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.indexPath

			let itemFrame = self.frameForItemAtIndexPath(idxPath)

			if CGRectIntersectsRect(itemFrame, rect) {

				let nAttr = self.layoutAttributesForItemAtIndexPath(idxPath)

				attrs?.append(nAttr!)

			}

		}

		

		return attrs

	}

	

}