uicollectionviewlayout

Warning: UICollectionViewFlowLayout has cached frame mismatch for index path ‘abc’

This is likely occurring because the flow layout “xyz” is modifying attributes returned by UICollectionViewFlowLayout without copying them And sure enough, that’s just what you are doing: private override func layoutAttributesForItemAtIndexPath(indexPath: NSIndexPath) -> UICollectionViewLayoutAttributes? { let attributes = super.layoutAttributesForItemAtIndexPath(indexPath) let distance = CGRectGetMidX(attributes!.frame) – self.midX; var transform = CATransform3DIdentity; transform = CATransform3DTranslate(transform, -distance, 0, -self.width); … Read more

iOS 10 bug: UICollectionView received layout attributes for a cell with an index path that does not exist

This happened to me when number of cells in collectionView changed. Turns out I was missing invalidateLayout after calling reloadData. After adding it, I haven’t experienced any more crashes. Apple has made some modifications to collectionViews in iOS10. I guess that’s the reason why we are not experiencing same problem on older versions. Here’s my … Read more

How to create a centered UICollectionView like in Spotify’s Player

In order to create an horizontal carousel layout, you’ll have to subclass UICollectionViewFlowLayout then override targetContentOffset(forProposedContentOffset:withScrollingVelocity:), layoutAttributesForElements(in:) and shouldInvalidateLayout(forBoundsChange:). The following Swift 5 / iOS 12.2 complete code shows how to implement them. CollectionViewController.swift import UIKit class CollectionViewController: UICollectionViewController { let collectionDataSource = CollectionDataSource() let flowLayout = ZoomAndSnapFlowLayout() override func viewDidLoad() { super.viewDidLoad() title = … Read more

UICollectionView Layout like SnapChat?

Based on a precedent answer adapted to your issue: -(id)initWithSize:(CGSize)size { self = [super init]; if (self) { _unitSize = CGSizeMake(size.width/2,80); _cellLayouts = [[NSMutableDictionary alloc] init]; } return self; } -(void)prepareLayout { for (NSInteger aSection = 0; aSection < [[self collectionView] numberOfSections]; aSection++) { //Create Cells Frames for (NSInteger aRow = 0; aRow < [[self … Read more

How to set cell spacing and UICollectionView – UICollectionViewFlowLayout size ratio?

Add these 2 lines layout.minimumInteritemSpacing = 0 layout.minimumLineSpacing = 0 So you have: // Do any additional setup after loading the view, typically from a nib. let layout: UICollectionViewFlowLayout = UICollectionViewFlowLayout() layout.sectionInset = UIEdgeInsets(top: 20, left: 0, bottom: 10, right: 0) layout.itemSize = CGSize(width: screenWidth/3, height: screenWidth/3) layout.minimumInteritemSpacing = 0 layout.minimumLineSpacing = 0 collectionView!.collectionViewLayout = … Read more