Adding 'n' number of collection view to UIStackView in swift - ios

Question

I have a ViewController Class where I'm putting scrollView and adding stackView as the subview. Now I want to add 'n' number of collectionView inside the stackView. I'm fetching data from server, there will be a different categories. If category A has data, then I need to create one collectionView for that. And I need to handle the data of corresponding collectionView in their class itself.
class ViewController: UIViewController {
var scrollView : UIScrollView!
var stackView : UIStackView!
var responseFullData : JsonFullDataResponse!
var responseData : JsonResponse!
override init(nibName nibNameOrNil: String?, bundle nibBundleOrNil: Bundle?) {
print("View Controller init")
super.init(nibName: nil, bundle: nil)
}
required init?(coder aDecoder: NSCoder) {
super.init(coder: aDecoder)
}
override func viewDidAppear(_ animated: Bool) {
print("View did appear")
scrollView.contentSize = CGSize(width: stackView.frame.width, height: stackView.frame.height)
}
override func viewDidLoad() {
super.viewDidLoad()
//loading all the data
loadAllJsonData()
//setting up scroll and stack views
setUpScrollAndStackView()
}
override func viewDidLayoutSubviews() {
super.viewDidLayoutSubviews()
print("inside layout")
scrollView.contentSize = CGSize(width: stackView.frame.width, height: stackView.frame.height)
}
func setUpScrollAndStackView() {
scrollView = UIScrollView()
scrollView.translatesAutoresizingMaskIntoConstraints = false
view.addSubview(scrollView)
view.addConstraints(NSLayoutConstraint.constraints(withVisualFormat: "H:|[scrollView]|", options: .alignAllCenterX, metrics: nil, views: ["scrollView": scrollView]))
view.addConstraints(NSLayoutConstraint.constraints(withVisualFormat: "V:|[scrollView]|", options: .alignAllCenterX, metrics: nil, views: ["scrollView": scrollView]))
stackView = UIStackView()
stackView.translatesAutoresizingMaskIntoConstraints = false
stackView.spacing = 20.0
stackView.axis = .vertical
scrollView.addSubview(stackView)
scrollView.addConstraints(NSLayoutConstraint.constraints(withVisualFormat: "H:|[stackView]|", options: NSLayoutFormatOptions.alignAllCenterX, metrics: nil, views: ["stackView": stackView]))
scrollView.addConstraints(NSLayoutConstraint.constraints(withVisualFormat: "V:|[stackView]", options: NSLayoutFormatOptions.alignAllCenterX, metrics: nil, views: ["stackView": stackView]))
setUpOtherViewsInStack()
}
func setUpOtherViewsInStack() {
if responseFullData.banner?.count != 0 {
print("banner has data")
var bannerCollection : BannerCollectionView = BannerCollectionView() as! BannerCollectionView
bannerCollection.register(UINib.init(nibName: "BannerCell", bundle: nil), forCellWithReuseIdentifier: "BannerCell")
stackView.addArrangedSubview(bannerCollection)
}
}
BannerCollectionView Code
class BannerCollectionView: UICollectionView , UICollectionViewDataSource{
required init?(coder aDecoder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int{
print("control is in datasource")
return 5
}
func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell{
let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "BannerCell", for: indexPath) as! BannerCell
cell.backgroundColor = UIColor.blue
return cell
}
}
How do I make this work. In which class and where I should set the delegate and datasource property of BannerCollectionView? How do I initialise this?

Answer 1

As I understand you need to make a for from 0 to count in responseFullData.banner.count adding a collectionView each time
if let count = responseFullData.banner?.count {
for i in 0..<count {
var bannerCollection : BannerCollectionView = BannerCollectionView() as! BannerCollectionView
bannerCollection.register(UINib.init(nibName: "BannerCell", bundle: nil), forCellWithReuseIdentifier: "BannerCell")
stackView.addArrangedSubview(bannerCollection)
}
}

Answer 2

I have added 3 collectionView inside the UIStackView(Vertical stack). The whole view can be scrolled vertically and the collection items can be scrolled either horizontally or vertically.
class HomePageViewController: UIViewController,HeaderViewDelegate {
var scrollView : UIScrollView!
var stackView : UIStackView!
var responseFullData : JsonFullDataResponse!
if responseFullData?.menu?.count != nil{
print("menu has data")
var menuCollection : MenuCollectionView = MenuCollectionView(frame: CGRect.zero, collectionViewLayout: UICollectionViewFlowLayout.init())
menuCollection.backgroundColor = .white
menuCollection.menuData = (self.responseFullData.menu)!
menuCollection.dataSource = menuCollection.self
menuCollection.delegate = menuCollection.self
createCollectionViews(collectionViewClass: menuCollection, identifier: "MenuCell",height : 175)
}
if responseFullData?.hongbei?.count != nil {
print("hongbei has data")
var hongbeiCollection : HongbeiCollectionView = HongbeiCollectionView(frame: CGRect.zero, collectionViewLayout: UICollectionViewFlowLayout.init())
hongbeiCollection.dataSource = hongbeiCollection
hongbeiCollection.delegate = hongbeiCollection
hongbeiCollection.allowsSelection = true
hongbeiCollection.backgroundColor = .white
hongbeiCollection.hongbeiData = (self.responseFullData.hongbei)!
addHeaderView(headerTitle : "Hongbei")
createCollectionViews(collectionViewClass: hongbeiCollection, identifier: "HongbeiCell",height : 150)
}
if responseFullData?.freeZone?.count != nil {
print("freezone has data")
var freezoneCollection : FreeZoneCollectionView = FreeZoneCollectionView(frame: CGRect.zero, collectionViewLayout: UICollectionViewFlowLayout.init())
freezoneCollection.dataSource = freezoneCollection.self
freezoneCollection.delegate = freezoneCollection.self
freezoneCollection.backgroundColor = .white
freezoneCollection.freeZoneData = (self.responseFullData.freeZone)!
addHeaderView(headerTitle : "FreeZone")
createCollectionViews(collectionViewClass: freezoneCollection, identifier: "FreeZoneCell",height : 150)
}
func createCollectionViews(collectionViewClass : UICollectionView, identifier : String,height : CGFloat ){
collectionViewClass.widthAnchor.constraint(equalToConstant: self.view.frame.width).isActive = true
collectionViewClass.heightAnchor.constraint(equalToConstant: height).isActive = true
collectionViewClass.register(UINib.init(nibName: identifier, bundle: nil), forCellWithReuseIdentifier: identifier)
collectionViewClass.showsHorizontalScrollIndicator = false
collectionViewClass.showsVerticalScrollIndicator = false
stackView.addArrangedSubview(collectionViewClass)
}
func addHeaderView(headerTitle : String){
let headerView = HeaderView.instanceFromNib() as! HeaderView
headerView.widthAnchor.constraint(equalToConstant: self.view.frame.width).isActive = true
headerView.heightAnchor.constraint(equalToConstant: 20).isActive = true
headerView.headerLabel.text = headerTitle
headerView.frame = headerView.frame.offsetBy(dx: 20, dy: 0)
headerView.delegate = self
stackView.addArrangedSubview(headerView)
}
}
class MenuCollectionView: UICollectionView,UICollectionViewDataSource,UICollectionViewDelegateFlowLayout {
var menuData : [MenuData]!
override init(frame: CGRect, collectionViewLayout layout: UICollectionViewLayout) {
let layout = UICollectionViewFlowLayout()
layout.scrollDirection = .horizontal
super.init(frame: frame, collectionViewLayout: layout)
}
func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int{
print("Menu")
return menuData.count
}
func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell{
let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "MenuCell", for: indexPath) as! MenuCell
cell.menuLabel.text = menuData[indexPath.item].title!
return cell
}
func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, sizeForItemAt indexPath: IndexPath) -> CGSize{
return CGSize(width: (collectionView.frame.width * 0.175), height: 75)
}
I have a separate class for each collectionView in the stack, where I handle the data source and delegate methods. So I can have any number for collection items I want in each collectionView.