How to call the correct datasource within the UICollectionViewDataSource and UICollectionViewDelegateFlowLayout methods?

Question

Within a UITableViewController, with static UITableViewCells, I am trying to create a reusable grid with a definite number of cells per row, variable widths and heights.

In Identifying and fixing auto layout issue from log output, it was suggested that UICollectionViews would be a better approach.

Using static UICollectionViewCells, as per https://robkerr.com/how-to-create-a-static-uicollectionview/, I have been able to set up one collection view grid.

BUT, I'm having difficulty adding a second, separate, and different grid in another UITableViewCell.

I thought I might be able to create separate IB outlets for the UICollectionView and then use this to select which data to use.

@IBOutlet weak var myCollectionView: UICollectionView!

@IBOutlet weak var endingsCV: UICollectionView!

extension NounsTVC: UICollectionViewDataSource
{
func collectionView( _ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int
{
    if self == myCollectionView
    {
        print("myCollectionView", cellIds.count)
        return cellIds.count}
    else if self == endingsCV
    {
        print("endingsCV", cellIds2.count)
        return cellIds2.count
    }
}

This crashes without finding the Collection View reuse identifiers.

I've tried using the UICollectionView Identity Restoration ID, but I might not have the correct syntax or placement.

How do I call the correct datasource to configure the cells within the UICollectionViewDataSource and UICollectionViewDelegateFlowLayout methods?

score 0 · Accepted Answer · answered Apr 24 '19 at 09:01

I'm not sure if this is the best way to do this, but it works if I use the instantiated name of the collection view instead of 'self'.

@IBOutlet weak var myCollectionView: UICollectionView!

@IBOutlet weak var endingsCV: UICollectionView!

extension NounsTVC: UICollectionViewDataSource
{
func collectionView( _ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int
{
if myCollectionView == myCollectionView
{
    print("myCollectionView", cellIds.count)
    return cellIds.count}
else if endingsCV == endingsCV
{
    print("endingsCV", cellIds2.count)
    return cellIds2.count
} }

How to call the correct datasource within the UICollectionViewDataSource and UICollectionViewDelegateFlowLayout methods?

1 Answers1