Issues with casting celltypes to dequeue
Hi i'm having issues in my cellForItemAt its saying the error below. I don't see why i'm unable to cast the cells. It occurs at the first line of the else statement.
The methods in the UIConstraintBasedLayoutDebugging category on UIView listed in may also be helpful.
Could not cast value of type 'Spoexs.MenuCell2' (0x10d059660) to 'Spoexs.MenuCell1' (0x10d0595c0).
import UIKit
import MIBadgeButton_Swift
class SecondMenuBar: UIView, UICollectionViewDataSource, UICollectionViewDelegate, UICollectionViewDelegateFlowLayout {
lazy var collectionView: UICollectionView = {
let layout = UICollectionViewFlowLayout()
let cv = UICollectionView(frame: .zero, collectionViewLayout: layout)
cv.backgroundColor = UIColor.rgb(r:240, g:240, b:240)
cv.dataSource = self
cv.delegate = self
return cv
}()
let cellId = "cellId"
let cellId2 = "cellId2"
let menuItems = ["inventory", "checkout", "scanner"]
var inventoryController: InventoryTabController?
override init(frame: CGRect){ //on run
super.init(frame: frame)
collectionView.register(MenuCell1.self,
forCellWithReuseIdentifier: cellId) //registering superclass
collectionView.register(MenuCell2.self,
forCellWithReuseIdentifier: cellId) //registering superclass
addSubview(collectionView)
addConstraintsWithFormat("H:|[v0]|", views: collectionView)
addConstraintsWithFormat("V:|[v0]|", views: collectionView)
let selectedIndexPath = NSIndexPath(item:0, section:0)
collectionView.selectItem(at: selectedIndexPath as IndexPath, animated: false, scrollPosition: []) //home button glows on run
//setup horizontal bar
slider()
NotificationCenter.default.addObserver(forName: .arrayValueChanged, object: nil, queue: OperationQueue.main) { [weak self] (notif) in
badge = "(checkout.count)"
self?.collectionView.reloadData()
}
}
deinit {
NotificationCenter.default.removeObserver(self)
}
var horizontalBarLeftAnchorConstraint: NSLayoutConstraint?
func slider() {
let horizontalBarView = UIView()
if #available(iOS 10.0, *) {
horizontalBarView.backgroundColor = UIColor(displayP3Red:0.29, green:0.78, blue:0.47, alpha:0.2)
} else {
horizontalBarView.backgroundColor = UIColor.rgb(r:190, g:190, b:190)
}
horizontalBarView.translatesAutoresizingMaskIntoConstraints = false
addSubview(horizontalBarView) //add to hierarchy
// need x,y coordinate
horizontalBarLeftAnchorConstraint = horizontalBarView.leftAnchor.constraint(equalTo: self.leftAnchor)
horizontalBarLeftAnchorConstraint?.isActive = true
horizontalBarView.bottomAnchor.constraint(equalTo: self.bottomAnchor).isActive = true
horizontalBarView.widthAnchor.constraint(equalTo: self.widthAnchor, multiplier: 1/3).isActive = true
horizontalBarView.heightAnchor.constraint(equalToConstant: 3).isActive = true
}
func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) {
inventoryController?.scrollToMenuIndex(menuIndex: indexPath.item)
print("Right here (indexPath.section)")
print("Right here (indexPath.item)")
}
func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, sizeForItemAt indexPath: IndexPath) -> CGSize {
return CGSize(width: frame.width/3, height: frame.height)
}
func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, minimumInteritemSpacingForSectionAt section: Int) -> CGFloat {
return 0
}
func collectionView(_ collectionView: UICollectionView,
numberOfItemsInSection section: Int) -> Int {
return 3
}
func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
if indexPath.section == 1{
let cell = collectionView.dequeueReusableCell(withReuseIdentifier: cellId2, for: indexPath) as! MenuCell2
cell.imageView2.setImage(UIImage(named:menuItems[indexPath.section])?.withRenderingMode(.alwaysTemplate), for: .normal)
cell.imageView2.badgeString = badge
cell.tintColor = UIColor.rgb(r:255, g:0, b:255) //set tint color
return cell
} else{
let cell = collectionView.dequeueReusableCell(withReuseIdentifier: cellId, for: indexPath) as! MenuCell1
cell.imageView1.image = UIImage(named: menuItems[indexPath.section])?.withRenderingMode(.alwaysTemplate)
cell.tintColor = UIColor.rgb(r:255, g:0, b:255) //set tint color
return cell
}
}
required init?(coder aDecoder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
}
class MenuCell1: UICollectionViewCell {
override init(frame: CGRect){
super.init(frame: frame)
setupViews()
}
required init?(coder aDecoder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
let imageView1: UIImageView = {
let iv = UIImageView()
iv.image = UIImage(named: "")?.withRenderingMode(.alwaysTemplate)
iv.tintColor = UIColor.rgb(r:144, g:157, b:255)//set tint color of each menu image bg
return iv
}()
override var isSelected: Bool {
didSet {
imageView1.tintColor = isSelected ? UIColor.rgb(r:76, g:200, b:120) : UIColor.rgb(r:190, g:190, b:190) //green when selected otherwise grey
}
}
func setupViews() {
addSubview(imageView1)
addConstraintsWithFormat("H:[v0(28)]", views: imageView1)
addConstraintsWithFormat("V:[v0(28)]", views: imageView1)
addConstraint(NSLayoutConstraint(item: imageView1, attribute: .centerX, relatedBy: .equal, toItem: self, attribute: .centerX, multiplier:1, constant: 0)) //center menu icons
addConstraint(NSLayoutConstraint(item: imageView1, attribute: .centerY, relatedBy: .equal, toItem: self, attribute: .centerY, multiplier:1, constant: 0))
}
}
class MenuCell2: UICollectionViewCell {
override init(frame: CGRect){
super.init(frame: frame)
setupViews()
}
required init?(coder aDecoder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
let imageView2: MIBadgeButton = {
let button = MIBadgeButton()
var image = UIImage(named: "home")?.withRenderingMode(.alwaysTemplate)
button.setImage(image, for: .normal)
button.badgeString = badge
button.isUserInteractionEnabled = false
button.tintColor = UIColor.rgb(r:190, g:190, b:190) //intital button tint grey
return button
}()
override var isSelected: Bool {
didSet {
imageView2.tintColor = isSelected ? UIColor.rgb(r:76, g:200, b:120) : UIColor.rgb(r:190, g:190, b:190) //green when selected otherwise grey
}
}
func setupViews() {
addSubview(imageView2)
addConstraintsWithFormat("H:[v0(28)]", views: imageView2)
addConstraintsWithFormat("V:[v0(28)]", views: imageView2)
addConstraint(NSLayoutConstraint(item: imageView2, attribute: .centerX, relatedBy: .equal, toItem: self, attribute: .centerX, multiplier:1, constant: 0)) //center menu icons
addConstraint(NSLayoutConstraint(item: imageView2, attribute: .centerY, relatedBy: .equal, toItem: self, attribute: .centerY, multiplier:1, constant: 0))
}
}
Your code for registering the cell classes is wrong:
collectionView.register(MenuCell1.self, forCellWithReuseIdentifier: cellId)
collectionView.register(MenuCell2.self, forCellWithReuseIdentifier: cellId) // <-- probably not intended
You are registering both classes for the same cellId , one should be cellId2 :
collectionView.register(MenuCell1.self, forCellWithReuseIdentifier: cellId)
collectionView.register(MenuCell2.self, forCellWithReuseIdentifier: cellId2)
The problem is this line:
let cell = collectionView.dequeueReusableCell(withReuseIdentifier: cellId, for: indexPath) as! MenuCell1
The cell you have registered for this reuse identifier is MenuCell2, so that is what you get. You cannot then magically turn it into a MenuCell1!
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