swift different number of cell in each section - swift

Question

I'm trying to pull data from firebase and show it in a collectionView with sections. How can add a different number of cells per section as each firebase data node will not have the same number of posts.
var users = [User]()
var posts = [Post]()
Updated collection view methods:
override func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
let cell = collectionView.dequeueReusableCell(withReuseIdentifier: cellId, for: indexPath) as! FollowingCell
let user = self.users[indexPath.section]
let post = self.dataSource[user]?[indexPath.row]
cell.post = post
return cell
}
override func collectionView(_ collectionView: UICollectionView, viewForSupplementaryElementOfKind kind: String, at indexPath: IndexPath) -> UICollectionReusableView {
let header = collectionView.dequeueReusableSupplementaryView(ofKind: kind, withReuseIdentifier: headerId, for: indexPath) as! FollowingHeader
let user = self.users[indexPath.section]
header.user = user
return header
}
override func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
let user = self.users[section]
return self.dataSource[user]?.count ?? 0
}
override func numberOfSections(in collectionView: UICollectionView) -> Int {
return self.dataSource.count
}
func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, sizeForItemAt indexPath: IndexPath) -> CGSize {
return CGSize(width: 120, height: 80)
}
How I'm adding the posts and user. As you can see I'm adding the post to the dataSource but for some reason, only 1 post per use is added when one of the users has two posts.
func fetchFollowedEvents() {
self.collectionView.refreshControl?.endRefreshing()
guard let currentUid = Auth.auth().currentUser?.uid else { return }
let ref = Database.database().reference().child("followed-posts").child(currentUid)
ref.observeSingleEvent(of: .value) { (snapshot) in
guard let dictionary = snapshot.value as? [String: Any] else { return }
dictionary.forEach { (key, value) in
Database.database().reference().child("posts").child(key).observeSingleEvent(of: .value) { (postSnapshot) in
guard let postDictionary = postSnapshot.value as? [String: Any] else { return }
guard let uid = postDictionary["uid"] as? String else { return }
Database.fetchUserWithUID(uid: uid) { (user) in
let post = Post(postId: key, user: user, dictionary: postDictionary)
post.id = key
self.users.append(user)
self.dataSource[user] = [post]
self.collectionView.reloadData()
}
}
}
}
}

Answer 1

try creating data source like this
var users : [User] = []()
var dataSource : [User:[Post]] = [:]() //I Prefer this one
(or)
var dataSource :[Int: [Post]] = [:]()
a dictionary with Users as Key and Array of post as Value
So now for number of sections you can use
self.userser.count()
(or)
self.dataSource.count()
So for number of rows in sections, you can do as so
let user = self.users[section]
return self.dataSource[user].count() ?? 0
(or)
return self.dataSource[section].count() ?? 0
in cell for row at index you can get the data as
let user = self.users[indexPath.section]
let data = self.dataSource[user][indexPath.row]
(or)
let data = self.dataSource[indexPath.section][indexPath.row]
Hope this would help you.
Happy Codding!