Unexpected behavior with nested collection views with constraints (Swift 4) - ios

Question

I have a cell in a tableview that contains a horizontal paging collection view.
Inside each page of this collection view there is a vertical collection view.
In order to avoid a "scroll-in-scroll" problem, I disabled vertical scrolling in the vertical collection views.
The vertical collection view's cell count is not static and can be any number.
So this creates a problem: the collection view (you'll have to ask me for clarification about which one) won't fit properly into the table view's cell anymore.
To solve this, I changed the table view's cell height by changing the constraints in the storyboard... but the problem remains.
Here is an image to help illustrate the problem:
and here is my code:
class myTBViewController: UITableViewController , UICollectionViewDelegate , UICollectionViewDataSource , UICollectionViewDelegateFlowLayout {
func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
if collectionView.tag == 10 {
return 2
} else {
return 30
}
}
func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
if collectionView.tag == 10 {
let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "mainPages", for: indexPath) as! mainPages
cell.backgroundColor = UIColor.yellow
cell.listCV.clipsToBounds = true
return cell
} else {
let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "showAdvCell", for: indexPath) as! showAdvCell
cell.backgroundColor = UIColor.red
return cell
}
}
func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, insetForSectionAt section: Int) -> UIEdgeInsets {
if collectionView.tag == 10 {
let collectionViewHeight = collectionView.frame.height
let itemsHeight = collectionView.contentSize.height
let topInset = ( collectionViewHeight - itemsHeight ) / 4
return UIEdgeInsetsMake(topInset ,0, 0 , 0)
} else {
let collectionViewHeight = collectionView.frame.height
let itemsHeight = CGFloat(80)
let topInset = ( collectionViewHeight - itemsHeight ) / 4
return UIEdgeInsetsMake(topInset ,0, 0 , 0)
}
}
var headerSegment = UISegmentedControl()
override func viewDidLoad() {
super.viewDidLoad()
headerSegment.frame = CGRect(x: 0, y: 200, width: UIScreen.main.bounds.width, height: 30)
let items = ["فروشگاه ها", "دیوار"]
headerSegment = UISegmentedControl(items: items)
headerSegment.selectedSegmentIndex = 0
headerSegment.addTarget(self, action: #selector(selectPage), for: UIControlEvents.valueChanged)
let frame = CGRect(x: 0, y: 0, width: UIScreen.main.bounds.width, height: 200)
let headerImageView = UIImageView(frame: frame)
let image: UIImage = UIImage(named: "1")!
headerImageView.image = image
let frame3 = CGRect(x: 0, y: 0, width: 80, height: 80)
let headerImageView2 = UIImageView(frame: frame3)
let image2: UIImage = UIImage(named: "1")!
headerImageView2.image = image2
headerSegment.addSubview(headerImageView2)
headerSegment.bringSubview(toFront: headerImageView2)
headerImageView2.center = CGPoint(x: UIScreen.main.bounds.width / 2, y: 200)
headerSegment.frame = CGRect(x: 0, y: 200, width: UIScreen.main.bounds.width + 10 , height: 40)
headerSegment.center = CGPoint(x: UIScreen.main.bounds.width / 2, y: 200)
let mainView = UIView(frame: CGRect(x: 0, y: 0, width: UIScreen.main.bounds.width, height: 230))
let headerSegmentView = UIView(frame : CGRect(x: 0, y: 200, width: UIScreen.main.bounds.width, height: 40))
headerSegmentView.center = headerSegment.center
headerSegmentView.backgroundColor = UIColor.white
mainView.addSubview(headerImageView)
mainView.bringSubview(toFront: headerImageView)
mainView.addSubview(headerSegmentView)
mainView.bringSubview(toFront: headerSegmentView)
mainView.addSubview(headerSegment)
mainView.bringSubview(toFront: headerSegment)
mainView.addSubview(headerImageView2)
mainView.bringSubview(toFront: headerImageView2)
self.tableView.tableHeaderView = mainView
headerImageView2.layer.borderWidth = 2
headerImageView2.layer.masksToBounds = false
headerImageView2.layer.borderColor = UIColor.init(white: 255/255, alpha: 0.3).cgColor
headerImageView2.layer.cornerRadius = headerImageView2.frame.height/2
headerImageView2.clipsToBounds = true
}
#objc func selectPage() {
let cell = self.tableView.dequeueReusableCell(withIdentifier: "myTBViewCell") as! myTBViewCell
switch headerSegment.selectedSegmentIndex {
case 0:
print("0")
cell.myTBCollectionView.scrollToItem(at:IndexPath(item: 0, section: 0), at: .top, animated: false)
case 1:
print("1")
cell.myTBCollectionView.scrollToItem(at:IndexPath(item: 1, section: 0), at: .top, animated: false)
default:
print("0")
cell.myTBCollectionView.scrollToItem(at:IndexPath(item: 0, section: 0), at: .top, animated: false)
}
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
override func numberOfSections(in tableView: UITableView) -> Int {
// #warning Incomplete implementation, return the number of sections
return 1
}
override func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
// #warning Incomplete implementation, return the number of rows
return 1
}
override func tableView(_ tableView: UITableView, heightForRowAt indexPath: IndexPath) -> CGFloat {
tableView.estimatedRowHeight = 200
tableView.rowHeight = UITableViewAutomaticDimension
return 600
}
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = self.tableView.dequeueReusableCell(withIdentifier: "myTBViewCell", for: indexPath) as! myTBViewCell
return cell
}
}

Answer 1

I have a similar Problem , finally, I have solved it by creating a height Constraint of CollectionView.
than setting CollectionView height Constraint based on CollectionView ContentSize.
self.collectionViewHeight.constant = self.recentCollectionView.collectionViewLayout.collectionViewContentSize.height
the alternative approach is to override systemLayoutSizeFitting method of tableViewCell
ex:
override func systemLayoutSizeFitting(_ targetSize: CGSize, withHorizontalFittingPriority horizontalFittingPriority: UILayoutPriority, verticalFittingPriority: UILayoutPriority) -> CGSize {
super.systemLayoutSizeFitting(targetSize, withHorizontalFittingPriority: horizontalFittingPriority, verticalFittingPriority: verticalFittingPriority)
self.tagCollectionView.layoutIfNeeded()
return self.tagCollectionView.collectionViewLayout.collectionViewContentSize
}
in addition you don't need to return fixed 600 height in your table view delegate heightForRowAtIndexPath