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Khoa Pham
Khoa Pham

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Making NSCollectionView programatically in Swift

#appkit #nscollectionview #swift

Original post https://github.com/onmyway133/blog/issues/131

Here's how to create NSCollectionView programatically. We need to embed it inside NScrollView for scrolling to work. Code is in Swift 4

NSCollectionView 

let layout = NSCollectionViewFlowLayout() layout.minimumLineSpacing = 4 collectionView = NSCollectionView() collectionView.dataSource = self collectionView.delegate = self collectionView.collectionViewLayout = layout collectionView.allowsMultipleSelection = false collectionView.backgroundColors = [.clear] collectionView.isSelectable = true collectionView.register( Cell.self, forItemWithIdentifier: NSUserInterfaceItemIdentifier(rawValue: "Cell") )
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NScrollView 

scrollView = NSScrollView() scrollView.documentView = collectionView view.addSubview(scrollView)
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NSCollectionViewItem 

final class Cell: NSCollectionViewItem { let label = Label() let myImageView = NSImageView() override func loadView() { self.view = NSView() self.view.wantsLayer = true } }
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NSCollectionViewDataSource 

func collectionView(_ collectionView: NSCollectionView, numberOfItemsInSection section: Int) -> Int { return coins.count } func collectionView(_ collectionView: NSCollectionView, itemForRepresentedObjectAt indexPath: IndexPath) -> NSCollectionViewItem { let cell = collectionView.makeItem( withIdentifier: NSUserInterfaceItemIdentifier(rawValue: "Cell"), for: indexPath ) as! Cell let coin = coins[indexPath.item] cell.label.stringValue = coin.name cell.coinImageView.image = NSImage(named: NSImage.Name(rawValue: "USD")) ?? NSImage(named: NSImage.Name(rawValue: "Others")) return cell }
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NSCollectionViewDelegateFlowLayout 

func collectionView(_ collectionView: NSCollectionView, didSelectItemsAt indexPaths: Set<IndexPath>) { guard let indexPath = indexPaths.first, let cell = collectionView.item(at: indexPath) as? Cell else { return } } func collectionView(_ collectionView: NSCollectionView, didDeselectItemsAt indexPaths: Set<IndexPath>) { guard let indexPath = indexPaths.first, let cell = collectionView.item(at: indexPath) as? Cell else { return } } func collectionView(_ collectionView: NSCollectionView, layout collectionViewLayout: NSCollectionViewLayout, sizeForItemAt indexPath: IndexPath) -> NSSize { return NSSize( width: collectionView.frame.size.width, height: 40 ) }
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Top comments (1)

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devulderjeanpaul profile image
DevulderJeanPaul •

on example
coinImageView doesn't exist remplace with myImageView