UICollectionView - random cells are selected

Question

I have a Horizontal UICollectionView like the horizontal Calender in iOS. Paging is enabled but not allowsMultipleSelection.

self.allowsMultipleSelection = fals         


        

Answer 1

First, if you want to preserve multiple selection, you have to remember your selected ones in an array since it would get lost if a cell gets recycled and reused. For that use something like a [IndexPath] type). If one selected cell is enough, you could use a non-array version of below code.

var selectedItems: [IndexPath] = []

Then, do your recoloring in your cell's cellForItemAt(:):

cell.backgroundColor = selectedItems.contains(indexPath) ? .red : .white

Your didSelectItemAt delegate function should look like:

if !selectedItems.contains(indexPath) { selectedItems.append(indexPath)}

collectionView.cellForItem(at: indexPath)?.backgroundColor = .red

and your didDeselectItemAt delegate function:

if let index = selectedItems.firstIndex(of: indexPath) { selectedItems.remove(at: index) }

collectionView.cellForItem(at: indexPath)?.backgroundColor = .white

This should actually work. Let me know if we have to do adjustments.