First cell and last cell are changing each other in UICollectionView - ios

Question

I have MenuItemCollectionView and FoodItemColletionView and I am setting FoodItemCollectionView in MenuItemColletionViewCell.Error happened in first MenuItemCell and last MenuItemCell are changing each other.But sometimes they are appeared right place.I have no idea to fix this error
This is MenuItemCollectionView
func numberOfSections(in collectionView: UICollectionView) -> Int {
print("Food Array Count = \(self.foodArray.count)")
return self.foodArray.count
}
func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
return 1
}
func collectionView(_ collectionView: UICollectionView, viewForSupplementaryElementOfKind kind: String, at indexPath: IndexPath) -> UICollectionReusableView {
switch kind {
case UICollectionElementKindSectionHeader:
let headerView = collectionView.dequeueReusableSupplementaryView(ofKind: kind, withReuseIdentifier: RESUABLE_VIEW, for: indexPath) as! CollectionReusableView
headerView.header.text = nameArray[indexPath.section]
return headerView
default:
assert(false, "Unexpected element kind")
}
}
func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, sizeForItemAt indexPath: IndexPath) -> CGSize {
let width = UIScreen.main.bounds.width
let height = UIScreen.main.bounds.height/3
return CGSize(width: width, height: height)
}
func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
let cell = collectionView.dequeueReusableCell(withReuseIdentifier: ITEM_CELL, for: indexPath) as! MenuItemCollectionViewCell
cell.foodArray.removeAll()
cell.foodArray = self.foodArray[nameArray[indexPath.section]]!
print("Cell COol index = \(indexPath.section) , ARrray count = \(cell.foodArray.count)")
return cell
}
This is MenuItemCollectionViewCell and I set up FoodItemColletionView in this
import UIKit
import SDWebImage
class MenuItemCollectionViewCell: UICollectionViewCell ,UICollectionViewDelegate,UICollectionViewDataSource{
#IBOutlet weak var foodItemColletion: UICollectionView!
var foodArray :[Food] = []
var imageArray : [UIImage?] = []
let FOOD_ITEM_CELL : String = "FoodCell"
override func awakeFromNib() {
foodItemColletion.delegate = self
foodItemColletion.dataSource = self
super.awakeFromNib()
}
override func prepareForReuse() {
foodArray.removeAll()
super.prepareForReuse()
}
func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
for food in foodArray{
print("Title Menu item \(food.title)")
}
return foodArray.count
}
func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
let cell = collectionView.dequeueReusableCell(withReuseIdentifier: FOOD_ITEM_CELL, for: indexPath) as! FoodItemCollectionViewCell
let foodObj = foodArray[indexPath.row]
cell.foodLabel.text = foodObj.title
cell.foodPrice.text = foodObj.price
cell.foodImage.sd_setImage(with: URL(string: "\(URLS.IMG_URL)\(foodObj.imageUrl)"), placeholderImage: nil, options: .refreshCached, progress: nil, completed: nil)
print("Title Menu Item Cell \(indexPath.item) = \(foodObj.title)")
return cell
}
}
This is FoodItemColletionViewCell
import UIKit
class FoodItemCollectionViewCell: UICollectionViewCell {
#IBOutlet weak var foodImage: UIImageView!
#IBOutlet weak var foodLabel: UILabel!
#IBOutlet weak var foodPrice: UILabel!
#IBOutlet weak var cardView: CardView!
override func awakeFromNib() {
foodImage.layer.masksToBounds = true
foodImage.roundCorners(corners: [.topLeft,.topRight], radius: 5)
cardView.setElevation(points: 1.5)
layer.shouldRasterize = true
layer.rasterizationScale = UIScreen.main.scale
cardView.layer.cornerRadius = 5
}
override func prepareForReuse() {
super.prepareForReuse()
foodImage.image = nil
}
}
extension UIImageView{
func roundCorners(corners:UIRectCorner, radius: CGFloat) {
let path = UIBezierPath(roundedRect: self.bounds, byRoundingCorners: corners, cornerRadii: CGSize(width: radius, height: radius))
let mask = CAShapeLayer()
mask.path = path.cgPath
self.layer.mask = mask
}
}
This is top screen that is actually what I want
This is bottom screen that is actually want I want too
But when i scroll fast again from top to bottom, first cell moved to last cell and last cell moved to first cell.This is what happened what i want to fix

Answer 1

In MenuItemCollectionView change this method:
func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
let cell = collectionView.dequeueReusableCell(withReuseIdentifier: ITEM_CELL, for: indexPath) as! MenuItemCollectionViewCell
cell.foodArray.removeAll()
cell.foodArray = self.foodArray[nameArray[indexPath.section]]!
// add this, or else because of reusing the old data will be presented, even though you have set the new one
cell.foodItemColletion.reloadData()
print("Cell COol index = \(indexPath.section) , ARrray count = \(cell.foodArray.count)")
return cell
}