Firebase storage data showing twice - ios

Question

Trying to load data in collection view with this method
func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
if urls.count == 0 {
return UICollectionViewCell()
}
let url = urls[indexPath.item]
let cell = collectionView.dequeueReusableCell(withReuseIdentifier: reuseIdentifier,
for: indexPath) as! ImageCollectionViewCell
storageRef.reference(withPath: url).getData(maxSize: 15 * 1024 * 1024, completion: { data, error in
if let data = data {
cell.imageView.image = UIImage(data: data)
}
})
return cell
}
The thing is - at first i can see both cells without data, then completion get called, an i'm getting a data, but the first image in both cells.
How can i do it right? And how can i get metadata in the same time too?
Screenshot:
UPD:
I wrote an array
var datas = ["first", "second", "third", "fourth"]
An changed cell code to
func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
let cell = collectionView.dequeueReusableCell(withReuseIdentifier: reuseIdentifier,
for: indexPath) as! ImageCollectionViewCell
cell.nameLabel.text = datas[indexPath.item]
return cell
}
And got this:
Still can't see what's wrong. My overrided methods:
func numberOfSections(in collectionView: UICollectionView) -> Int {
return 2
}
func collectionView(_ collectionView: UICollectionView,
numberOfItemsInSection section: Int) -> Int {
return datas.count / 2
}
SOLVED. Should return numberOfSections = 1

Answer 1

I think the problem is that you're downloading the information in the cellForItemAt indexPath: function and you should download the images in another function like this
//Variable to store the UIImages
var images = [UIImage]()
//function to download the images, run it in the viewdidload like self.getImages()
func getImages(){
for url in self.urls{
storageRef.reference(withPath: url).getData(maxSize: 15 * 1024 * 1024, completion: { data, error in
if let data = data {
self.images.append(UIImage(data: data))
}
})
}
self.YourCollectionView.reloadData()
}
func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
if urls.count == 0 {
return UICollectionViewCell()
}
let cell = collectionView.dequeueReusableCell(withReuseIdentifier: reuseIdentifier,
for: indexPath) as! ImageCollectionViewCell
cell.imageView.image = self.images[indexPath.row]
return cell
}

Answer 2

Should return 1 in numberOfSection func
func numberOfSections(in collectionView: UICollectionView) -> Int {
return 2
}