uiCollectionView inside a uiCollectionViewCell is not scrolling horizontally - swift

Question

Hey Everyone and thank you for taking your time to view this, I am trying to make a uiCollectionView scroll horizontally within a uiCollectionViewCell, the background and elements are showing but im unable to scroll, the uiCollectionViewcontaining the uiCollectionViewCell (which contains the uiCollectionView i need to scroll horizontally) in scrolling vertically as expected. Below are the relative classes:
The uiCollectionView and its uiCollectionViewCells which contains the uiCollectionView that needs horizontal scrolling, in the collectionView method the cases that needs scrolling are Prop4 and Countries:
lazy var collView: UICollectionView = {
let sub = SubclassedCollectionViewCell.self
let layout: UICollectionViewFlowLayout = UICollectionViewFlowLayout()
layout.itemSize = CGSize(width: self.view.frame.width, height:self.view.frame.height/100)
layout.scrollDirection = .vertical
// layout.minimumLineSpacing = 1000
layout.sectionInset = UIEdgeInsets(top:100, left: 0, bottom: 100, right: 0)
print("the frame",self.view.frame)
let view = UICollectionView(frame: CGRect(x:0, y:0, width: self.view.frame.width, height: self.view.frame.height), collectionViewLayout: layout)
view.register(sub, forCellWithReuseIdentifier: "profInfo")
view.backgroundColor = .clear
view.isUserInteractionEnabled = true
view.dataSource = self
view.delegate = self
return view
}()
public func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
let myCell = collectionView.dequeueReusableCell(withReuseIdentifier: "profInfo", for: indexPath) as! SubclassedCollectionViewCell
myCell.isUserInteractionEnabled = true
myCell.frame = CGRect(x: 10, y: (indexPath.row+1)*75, width: Int(self.view.frame.width) - 10, height: 50)
myCell.backgroundColor = .clear
let v = UIView(frame: CGRect(x: 0, y: 0, width: 150, height: 50))
let v2 = UIView(frame: CGRect(x: 150, y: 0, width: Int(self.view.frame.width) - 160, height: 50))
let label = UILabel(frame: CGRect(x: 0, y: 0, width: 200, height: 21))
let label2 = UILabel(frame: CGRect(x: 0, y: 0, width: 200, height: 21))
let imageV = UIImageView(frame: CGRect(x: 0, y: 12.5, width: 25, height: 25))
let imageV2 = UIImageView(frame: CGRect(x: 0, y: 12.5, width: 25, height: 25))
label.center = CGPoint(x: 150, y: 25)
label.textColor = .white
label2.textColor = .white
label2.center = CGPoint(x: 115, y: 25)
label2.textAlignment = .center
imageV2.center = CGPoint(x: 115, y: 25)
label.text = prof!.arrInfo[indexPath.row].title + ":"
print("array info", prof!.arrInfo)
switch(prof!.arrInfo[indexPath.row].title){
case "Prop1" :
imageV.image = UIImage(named: "art.scnassets/prop1.png")?.resized(to: CGSize(width: 10, height: 10))
label2.text = prof!.arrInfo[indexPath.row].text
v2.addSubview(label2)
break;
case "DOB" :
imageV.image = UIImage(named: "art.scnassets/DOB.png")?.resized(to: CGSize(width: 10, height: 10))
label2.text = getDOBFormat(dateStr: prof!.arrInfo[indexPath.row].text!)
v2.addSubview(label2)
break;
case "Prop3" :
imageV.image = UIImage(named: "art.scnassets/prop3.png")?.resized(to: CGSize(width: 10, height: 10))
imageV2.image = UIImage(named: prof!.arrInfo[indexPath.row].text!)?.resized(to: CGSize(width: 10, height: 10))
break;
case "Prop4" :
imageV.image = UIImage(named: "art.scnassets/prop4.png")?.resized(to: CGSize(width: 10, height: 10))
collectionViews[prof!.arrInfo[indexPath.row].title] = GeneralCollectionView()
collectionViews[prof!.arrInfo[indexPath.row].title]?.type = "Images"
collectionViews[prof!.arrInfo[indexPath.row].title]?.data = prof!.arrInfo[indexPath.row].selected
myCell.contentView.addSubview(collectionViews[prof!.arrInfo[indexPath.row].title]!.Container)
break;
case "Countries" :
imageV.image = UIImage(named: "art.scnassets/translation.png")?.resized(to: CGSize(width: 10, height: 10))
collectionViews[prof!.arrInfo[indexPath.row].title] = GeneralCollectionView()
collectionViews[prof!.arrInfo[indexPath.row].title]?.type = "Countries"
collectionViews[prof!.arrInfo[indexPath.row].title]?.data = prof!.arrInfo[indexPath.row].selected
myCell.contentView.addSubview(collectionViews[prof!.arrInfo[indexPath.row].title]!.Container)
break;
case "location":
imageV.image = UIImage(named: "art.scnassets/location.png")?.resized(to: CGSize(width: 10, height: 10))
label2.text = prof!.arrInfo[indexPath.row].text
v2.addSubview(label2)
break;
default:
break;
}
v.addSubview(label)
v.addSubview(imageV)
v2.addSubview(imageV2)
myCell.contentView.addSubview(v)
myCell.contentView.addSubview(v2)
return myCell
}
And this is the uiCollectionView that needs Horizontal scrolling and thats within the uiCollectionViewCell:
public class GeneralCollectionView:NSObject,UICollectionViewDelegate,UICollectionViewDataSource{
weak var parent:AnyObject?
var data:[String]?
var type:String?
lazy var Container: UICollectionView = {
let sub = SubclassedCollectionViewCell.self
let layout: UICollectionViewFlowLayout = UICollectionViewFlowLayout()
layout.itemSize = CGSize(width: 50, height:50)
layout.scrollDirection = .horizontal
let view = UICollectionView(frame: CGRect(x:150, y:0, width: 250, height: 50), collectionViewLayout: layout)
view.showsHorizontalScrollIndicator = false
view.isDirectionalLockEnabled = true
view.isScrollEnabled = true
view.isPagingEnabled = true
view.isUserInteractionEnabled = true
view.alwaysBounceHorizontal = true
view.clipsToBounds = true
view.translatesAutoresizingMaskIntoConstraints = false
view.register(sub, forCellWithReuseIdentifier: "myGenCell")
view.dataSource = self
view.delegate = self
view.backgroundColor = .white
layout.sectionInset = UIEdgeInsets(top:0, left: 10, bottom: 0, right: 10)
layout.minimumLineSpacing = 10 // space between rows
layout.minimumInteritemSpacing = 5 // space between items in the same
layout.itemSize = CGSize(width: 50, height: 50)
return view
}()
public func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
return data!.count
}
public func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
let myCell = collectionView.dequeueReusableCell(withReuseIdentifier: "myGenCell", for: indexPath) as! SubclassedCollectionViewCell
myCell.isUserInteractionEnabled = true
if type == "Countries"{
let country = data![indexPath.item].split(separator: "-")
let label = UILabel()
label.frame.size = CGSize(width: 50, height: 50)
label.text = countryFlag(country: String(country[1]))
label.center = CGPoint(x: 30, y: 25)
myCell.contentView.addSubview(label)
print(label, countryFlag(country: String(country[1])))
} else {
let val = data![indexPath.item]
let imgView = UIImageView()
imgView.frame.size = CGSize(width: 20, height: 20)
imgView.image = UIImage(named: val)?.resized(to: CGSize(width: 25, height: 25))
imgView.center = CGPoint(x: 30, y: 25)
myCell.contentView.addSubview(imgView)
}
return myCell
}
}

Answer 1

It is because v2 is added after the horizontal collection view, therefore coming on top blocking all user interactions like your scroll gestures.
Give all your views different background colors to debug this sort of thing.
Set isUserInteractionEnabled = false to v2 and any other view blocking your scroll gestures.
Besides that,
Check out Modern collection views to get some examples of how to build a collection view.
Checkout Auto layout to properly size your views.