In viewDidLoad I register the cell like this:
let cellIdentifier = "Cell"
override func viewDidLoad() {
super.viewDidLoad()
let cellNib = UINib(nibName: "ViewCell", bundle: nil)
collection.register(cellNib, forCellWithReuseIdentifier: cellIdentifier)
}
and in cellForItemAt of the UICollectionViewDataSource I do:
func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
// It crashes while trying to dequeue with the Error message: Assertion failure in -[UICollectionView _dequeueReusableViewOfKind:withIdentifier:forIndexPath:viewCategory:]
let dequedCell = collection.dequeueReusableCell(withReuseIdentifier: cellIdentifier, for: indexPath)
return dequedCell
}
The onlystrange thing might be that the code is Mixed Swift/ObjC, and ViewCell is ObjC and gets imported in the bridging header:
#import "ViewCell.h"
I am getting the following error:
*** Assertion failure in -[UICollectionView _dequeueReusableViewOfKind:withIdentifier:forIndexPath:viewCategory:],
/BuildRoot/Library/Caches/com.apple.xbs/Sources/UIKit_Sim/UIKit-3600.7.47/UICollectionView.m:5106
I made sure all names are correct. Does anyone know why this crash is happening??
Here is problem
1) You need to register cell identifier in XIB,
2) Assign Class name to XIB
3) cell for row you need to check with as? YourClass in dequeue and
4) dequeue with same identifier you assign to XIB and register
Set collectionview cell identifier as Cell in storyboard.
Does anyone know why this crash is happening?
One thing to consider is that the docs for register(_:forCellWithReuseIdentifier:) say:
The nib file must contain only one top-level object and that object must be of the type UICollectionViewCell.
So, check that that's true. In other words...
let nibObjects = cellNib.instantiate(withOwner: nib, options: nil)
let count = nibObjects.count // is this 1?
let view = nibObjects.first // is view a UICollectionViewCell?
I'm working through an exercise which uses tableviews. I noticed within a test during the exercise, they use a method I haven't needed in the past when implementing tableviews from storyboards. The method is:
func register(AnyClass?, forCellReuseIdentifier: String)
After reading the short description of this function in the reference pages. I'm curious to know what does apple mean by term "registers"? I half assume that since we are doing this exercise programmatically at the moment, this function is only needed if you're creating UITableviews programmatically. If this statement is incorrect, please let me know as I'd like to learn more.
Here is the code from the example:
func test_CellForRow_DequesCellFromTableView(){
let mockTableView = MockTableView()
mockTableView.dataSource = sut
mockTableView.delegate = sut
mockTableView.register(ItemCell.self, forCellReuseIdentifier: "ItemCell")
sut?.itemManger?.add(ToDoItem.init(title: "Foo"))
mockTableView.reloadData()
_ = mockTableView.cellForRow(at: IndexPath.init(row: 0, section: 0))
XCTAssertTrue(mockTableView.cellGotDequeed)
}
The DequeueReusable methods are there to check if any reusable cells are left before creating new ones. Hope you have an idea about the working of reusable cells
What happens when the queue is empty? Now we do need to create a cell. We can follow 2 methods to create a cell,
Create cell manually
Create it automatically by registering cell with a valid xib file
METHOD 1
if you do it with manually, you must check cell is empty or not after dequeueReusableCell check. Just like below,
// create a cell for each table view row
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
// Reuse an old cell if exist else return nil
let cell:UITableViewCell = self.tableView.dequeueReusableCell(withIdentifier: cellReuseIdentifier) as UITableViewCell!
//check cell is nil if nil you want to allocate it with proper cell
if(cell == nil){
//create cell manually
cell = UITableViewCell(style: UITableViewCellStyle.Subtitle, reuseIdentifier: "CellSubtitle")
}
// do stuff to the cell here
return cell
}
METHOD 2
We could create the cell manually like above which is totally fine. But it would be convenient if the table view would create the cell for us directly.
That way we don't have to load it from a nib or instantiate it.
For registering a cell with a xib or class we use func register(AnyClass?, forCellReuseIdentifier: String) method. Let see an example,
override func viewDidLoad() {
super.viewDidLoad()
self.tableView.register(MyCell.self, forCellReuseIdentifier: "Cell")
}
// ...
override func tableView(tableView: UITableView!, cellForRowAtIndexPath indexPath: NSIndexPath!) -> UITableViewCell! {
let cell = tableView.dequeueReusableCellWithIdentifier("Cell", forIndexPath:indexPath) as MyCell
// no "if" - the cell is guaranteed to exist
// ... do stuff to the cell here ...
cell.textLabel.text = // ... whatever
// ...
return cell
}
You are "registering" your custom Cell class - ItemCell - for reuse as a cell for your tableview.
See: https://developer.apple.com/reference/uikit/uitableview/1614888-register
"Register" tells XCode that the cell exists. A cell is registered under a "reuse identifier." This is a unique string that corresponds to your TableViewCell, in this case ItemCell.
A cell can also be registered in the Storyboard by filling out the "Identifier" in the cell's attributes inspector.
I have a ViewController with a UICollectionView where I'd like to display the first two letters of the players in the users friend list, like this:
func collectionView(collectionView: UICollectionView,
cellForItemAtIndexPath indexPath: NSIndexPath) -> UICollectionViewCell {
contactListCollection.registerClass(PlayerCell.self, forCellWithReuseIdentifier: "PlayerCell")
let cell = collectionView.dequeueReusableCellWithReuseIdentifier("PlayerCell", forIndexPath: indexPath) as! PlayerCell
let contacts = contactList.getContactList() //Array of strings
for(var i = 0; i < contacts.count; i++){
var str = contacts[i]
// First two letters
let firstTwo = Range(start: str.startIndex,
end: str.startIndex.advancedBy(2))
str = str.substringWithRange(firstTwo)
cell.setButtonTitle(str);
}
return cell;
}
func collectionView(collectionView: UICollectionView,
numberOfItemsInSection section: Int) -> Int {
return contactList.getContactList().count;
}
My PlayerCell Class is as follows:
class PlayerCell : UICollectionViewCell {
#IBOutlet var button: UIButton?
func setButtonTitle(text: String){
button!.setTitle(text, forState: .Normal)
}
}
When run the code it gives:
Fatal error: unexpectedly found nil while unwrapping an Optional value
I found out that the button in my PlayerCell is nil
I have added the button inside my cell in the Storyboard and Connected those with referencing outlets
Am I missing something here?
Using xCode 7 with Swift 2.0
As part of the compilation process, Xcode converts the storyboard to a collection of XIB files. One of those XIB files contains your cell design.
When your app loads the collection view controller that you designed in the storyboard, the controller takes care of registering the cell's XIB file for the cell.
You are overwriting that registration by calling registerClass(_:forCellWithReuseIdentifier:), severing the connection between the “PlayerCell” reuse identifier and the XIB containing the design of PlayerCell.
Get rid of this line:
contactListCollection.registerClass(PlayerCell.self, forCellWithReuseIdentifier: "PlayerCell")
Also, make sure that in the storyboard you have set the cell's reuse identifier to "PlayerCell".
Try:
1. I would check that there isn't an old referencing outlet attached to the button. Right click on the button in the interface builder and ensure that only the appropriate outlet is still connected.
Ensure that in the storyboard you have set the class of the re-useable cell to PlayerCell
Ensure that you have Ctrl + dragged from the collection view to the view controller it is in and set the delegate and data source to itself.
Hopefully, one of these may help you.
I recently tried changing my UITableViewController to a UITableView within a UIView. I changed back to this as I was experiencing an error with my UISearchBar, as when I would tap a key to search my app would crash with the error:
fatal error: unexpectedly found nil while unwrapping an Optional value
on this line:
var cell = tableView.dequeueReusableCellWithIdentifier("rideCell") as! RideCell
When I switched back to the UITableViewController this error went away and everything was fine, however I've just tested it again and it is again giving me that error.
Anyone have any suggestions? It works fine for the normal table view, it's just when I go to do a search that it crashes. The identifier is definitely correct.
Thanks!
EDIT:
Full function:
override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
var cell = tableView.dequeueReusableCellWithIdentifier("rideCell", forIndexPath: indexPath) as! RideCell
var ride: Ride
if tableView == self.searchDisplayController?.searchResultsTableView {
ride = DataManager.sharedInstance.getRideByName(searchResults[indexPath.row].name)!
} else {
ride = DataManager.sharedInstance.rideAtLocation(indexPath.row)!
}
cell.rideNameLabel.text = ride.name
var dateSinceUpdate = NSDate().timeIntervalSinceDate(ride.updated!)
var secondsSinceUpdate = Int(dateSinceUpdate)
var timeSinceUpdate = printSecondsConvert(secondsSinceUpdate)
cell.updatedLabel.text = timeSinceUpdate
if ride.waitTime == "Closed" {
cell.waitTimeLabel.text = ride.waitTime!
cell.timeBackgroundView.backgroundColor = getColorFromNumber(80)
cell.waitTimeLabel.font = UIFont(name: "Avenir", size: 13)
} else {
cell.waitTimeLabel.text = "\(ride.waitTime!)m"
cell.timeBackgroundView.backgroundColor = getColorFromNumber(ride.waitTime!.toInt()!)
cell.waitTimeLabel.font = UIFont(name: "Avenir", size: 17)
}
AsyncImageLoader.sharedLoader().cancelLoadingURL(cell.rideImageView.imageURL)
cell.rideImageView.image = UIImage(named: "Unloaded")
cell.rideImageView.imageURL = NSURL(string: ride.rideImageSmall!)
return cell
}
Discovered an extremely simple solution to the issue. Had to change this:
var cell = tableView.dequeueReusableCellWithIdentifier("rideCell", forIndexPath: indexPath) as! RideCell
to this:
var cell = self.tableView.dequeueReusableCellWithIdentifier("rideCell", forIndexPath: indexPath) as! RideCell
There are a few possibilities that you are seeing a fatal error of nil message in your dialog.
Possibility #1: Make sure you have a subclass of UITableViewCell named RideTableViewCell.swift.
To create a subclass of UITableViewCell simply follow the procedures below.
Right-Click on your Project name and create New File... in
Project Navigator
From iOS->Source create Cocoa Touch Class
In Option Dialog Subclass Field Type UITableViewCell
I believe you have an Custom XIB file already, if not, Check Also create XIB file
Make sure you input your XIB identifier in Attribute Inspector
Register your cell class in viewDidLoad() function like so:
let nibCell = UINib(nibName: "RideTableViewCell", bundle: nil)
self.tableView.registerNib(nibPosts, forCellReuseIdentifier: "RideCell")
Register your custom cell in cellForRowAtIndexPath like so:
let cell: RideTableViewCell = self.tableView.dequeueReusableCellWithIdentifier("RideCell", forIndexPath: indexPath) as! RideTableViewCell
Possibility #2: Maybe when you create your custom XIB you didn't tell it which class it belongs to. To set the class of XIB, follow the procedures below.
Click on your .xib file in Project Navigator
Go to identity inspector of your cell and make sure RideTableViewCell is in there.
Please comment if you have any question. Cheers!
Please check did you have given proper class name (RideCell), filled proper module(Your target) and finally the identifier in the storyboard. If this is ok please share SS of your storyboard tableView cell.
and
Hope it helps
If you are not using UITableViewController, then check the following extension are added or not.
class XYZViewController: UIViewController, UITableViewDataSource, UITableViewDelegate,UISearchBarDelegate, UISearchDisplayDelegate, UISearchResultsUpdating
{
or Check this Tutorial. It might help you to solve this error.
Please check that your delegates have been properly set in viewDidLoad and that you are inheriting delegate methods of UITableView and search functions like so:
class YourClass: UIViewController, UITableViewDelegate, UITableViewDataSource {
func viewDidLoad() {
tableView.delegate = self
tableView.dataSource = self
}
}
and do the same for the search bar delegates and data sources. More on that here.
It is showing nil because there is no UItableViewCell which is of type RideCell. You have to create a new RideCell.swift which will be a subclass of UITableViewCell and then associate that with the cell of your tableView and then proceed .
Make sure you fill the correct parameters in the code below.
private let cellReuseIdentifier = "MyCell"
tableView.registerNib(UINib(nibName: "MyCell", bundle: nil), forCellReuseIdentifier: cellReuseIdentifier)
My UITableViewController is causing a crash with the following error message:
Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: 'unable to dequeue a cell with identifier Cell - must register a nib or a class for the identifier or connect a prototype cell in a storyboard'
I understand that I need to register a nib or a class but I don't understand 'where or how?'.
import UIKit
class NotesListViewController: UITableViewController {
#IBOutlet weak var menuButton: UIBarButtonItem!
override func viewDidLoad() {
super.viewDidLoad()
NSNotificationCenter.defaultCenter().addObserver(self,
selector: "preferredContentSizeChanged:",
name: UIContentSizeCategoryDidChangeNotification,
object: nil)
// Side Menu
if self.revealViewController() != nil {
menuButton.target = self.revealViewController()
menuButton.action = "revealToggle:"
self.view.addGestureRecognizer(self.revealViewController().panGestureRecognizer())
}
}
override func viewDidAppear(animated: Bool) {
super.viewDidAppear(animated)
// whenever this view controller appears, reload the table. This allows it to reflect any changes
// made whilst editing notes
tableView.reloadData()
}
func preferredContentSizeChanged(notification: NSNotification) {
tableView.reloadData()
}
// #pragma mark - Table view data source
override func numberOfSectionsInTableView(tableView: UITableView) -> Int {
return 1
}
override func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return notes.count
}
override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCellWithIdentifier("Cell", forIndexPath: indexPath) as UITableViewCell
let note = notes[indexPath.row]
let font = UIFont.preferredFontForTextStyle(UIFontTextStyleHeadline)
let textColor = UIColor(red: 0.175, green: 0.458, blue: 0.831, alpha: 1)
let attributes = [
NSForegroundColorAttributeName : textColor,
NSFontAttributeName : font,
NSTextEffectAttributeName : NSTextEffectLetterpressStyle
]
let attributedString = NSAttributedString(string: note.title, attributes: attributes)
cell.textLabel?.font = UIFont.preferredFontForTextStyle(UIFontTextStyleHeadline)
cell.textLabel?.attributedText = attributedString
return cell
}
let label: UILabel = {
let temporaryLabel = UILabel(frame: CGRect(x: 0, y: 0, width: Int.max, height: Int.max))
temporaryLabel.text = "test"
return temporaryLabel
}()
override func tableView(tableView: UITableView, heightForRowAtIndexPath indexPath: NSIndexPath) -> CGFloat {
label.font = UIFont.preferredFontForTextStyle(UIFontTextStyleHeadline)
label.sizeToFit()
return label.frame.height * 1.7
}
override func tableView(tableView: UITableView, commitEditingStyle editingStyle: UITableViewCellEditingStyle, forRowAtIndexPath indexPath: NSIndexPath) {
if editingStyle == .Delete {
notes.removeAtIndex(indexPath.row)
tableView.deleteRowsAtIndexPaths([indexPath], withRowAnimation: .Fade)
}
}
// #pragma mark - Navigation
// In a storyboard-based application, you will often want to do a little preparation before navigation
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject!) {
if let editorVC = segue.destinationViewController as? NoteEditorViewController {
if "CellSelected" == segue.identifier {
if let path = tableView.indexPathForSelectedRow() {
editorVC.note = notes[path.row]
}
} else if "AddNewNote" == segue.identifier {
let note = Note(text: " ")
editorVC.note = note
notes.append(note)
}
}
}
}
You can register a class for your UITableViewCell like this:
With Swift 3+:
self.tableView.register(UITableViewCell.self, forCellReuseIdentifier: "cell")
With Swift 2.2:
self.tableView.registerClass(UITableViewCell.self, forCellReuseIdentifier: "cell")
Make sure same identifier "cell" is also copied at your storyboard's UITableViewCell.
"self" is for getting the class use the class name followed by .self.
Have you set the Table Cell identifier to "Cell" in your storyboard?
Or have you set the class for the UITableViewController to your class in that scene?
This worked for me, May help you too :
Swift 4+ :
self.tableView.register(UITableViewCell.self, forCellWithReuseIdentifier: "cell")
Swift 3 :
self.tableView.register(UITableViewCell.classForKeyedArchiver(), forCellReuseIdentifier: "Cell")
Swift 2.2 :
self.tableView.registerClass(UITableViewCell.classForKeyedArchiver(), forCellReuseIdentifier: "Cell")
We have to Set Identifier property to Table View Cell as per below image,
I had this issue today which was solved by selecting Product -> Clean. I was so confused since my code was proper. The problem started from using command-Z too many times :)
y my case i solved this by named it in the "Identifier" property of Table View Cell:
Don't forgot: to declare in your Class: UITableViewDataSource
let cell = tableView.dequeueReusableCell(withIdentifier: "cell", for: indexPath) as UITableViewCell
Just drag a cell (as you did for TableViewController) and add in to it just by releasing the cell on TableViewController. Click on the cell and.Go to its attributes inspector and set its identifier as "Cell".Hope it works.
Don't forget you want Identifier on the Attributes Inspector.
(NOT the "Restoration ID" on the "Identity Inspector" !)
Match the identifier name at both places
This error occurs when the identifier name of the Tablecell is different in the Swift file and in the Storyboard.
For example, the identifier is placecellIdentifier in my case.
1) The Swift File
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "placecellIdentifier", for: indexPath)
// Your code
return cell
}
2) The Storyboard
One more reason for this issue to happen is an earlier problem. When showing a new ViewController, instantiating the target ViewController directly will of course not load the prototype cells from the StoryBoard. The correct solution should always be to instantiate the view controller through the story board like this:
storyboard?.instantiateViewController(withIdentifier: "some_identifier")
In Swift 3.0, register a class for your UITableViewCell like this :
tableView.register(UINib(nibName: "YourCellXibName", bundle: nil), forCellReuseIdentifier: "Cell")
I had the same problem. This issue worked for me. In storyboard select your table view and change it from static cells into dynamic cells.
My problem was I was registering table view cell inside dispatch queue asynchronously. If you have registered table view source and delegate reference in storyboard then dispatch queue would delay the registration of cell as name suggests it will happen asynchronously and your table view is looking for the cells.
DispatchQueue.main.async {
self.tableView.register(CampaignTableViewCell.self, forCellReuseIdentifier: CampaignTableViewCell.identifier())
self.tableView.reloadData()
}
Either you shouldn't use dispatch queue for registration OR do this:
DispatchQueue.main.async {
self.tableView.dataSource = self
self.tableView.delegate = self
self.tableView.register(CampaignTableViewCell.self, forCellReuseIdentifier: CampaignTableViewCell.identifier())
self.tableView.reloadData()
}
There is two way you can define cell. If your table cell is inside on your ViewControllern then get the cell this way:
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "TableViewCell", for: indexPath) as! TableViewCell
// write your code here
return cell
}
But if you define cell outside of your ViewController then call the sell this way:
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = Bundle.main.loadNibNamed("TableViewCell", owner: self, options: nil)?.first as! TableViewCell
// write your code here
return cell
}
And as everyone said don't forget to set your cell identifier:
Stupid mistake:
make sure you add register(TableViewCell.self, forCellReuseIdentifier: "Cell") instead of register(TableViewCell.self, forHeaderFooterViewReuseIdentifier: "Cell")
If you defined your cell through the Interface Builder, by placing a cell inside your UICollectionView, or UITableView :
Make sure you binded the cell with an actual class you created, and very important, that you checked "Inherit module from target"
It used to work on swift 3 and swift 4 but now its not working.
like
self.tableView.register(MyTestTableViewCell.self, forCellReuseIdentifier: "cell")
So I have tried the most of the solutions mentioned above in swift 5 but did not get any luck.
Finally I tried this solution and it worked for me.
override func viewDidLoad()
{
tableView.register(UINib.init(nibName: "MyTestTableViewCell", bundle: nil), forCellReuseIdentifier: "myTestTableViewCell")
}
I just met the same issue and see this post. For me it's because I forgot the set the identifier of cell, also as mentioned in other answers. What I want to say is that if you are using the storyboard to load custom cell we don't need to register the table view cell in code, which can cause other problems.
See this post for detail:
Custom table view cell: IBOutlet label is nil
Swift 5
you need to use UINib method to register cell in viewDidLoad
override func viewDidLoad()
{
super.viewDidLoad()
// Do any additional setup after loading the view.
//register table view cell
tableView.register(UINib.init(nibName: "CustomTableViewCell", bundle: nil), forCellReuseIdentifier: "CustomTableViewCell")
}
I had the same issue where I registered my custom UITableViewCell classes within the viewDidLoad() which threw this error. To fix it what I did was registered the cells within the didSet property observer, as shown below
#IBOutlet tableview : UITableView! {
didSet {
tableview.register(CustomCell.self, forCellReuseIdentifier: "Cell")
}
}
Just for those new to iOS buddies (like me) who decided to have multiple cells and in a different xib file, the solution is not to have identifier but to do this:
let cell = Bundle.main.loadNibNamed("newsDetails", owner: self, options: nil)?.first as! newsDetailsTableViewCell
here newsDetails is xib file name.
I ran into this message when UITableView in the IB was moved into another subview with Cmd-C - Cmd-V.
All identifiers, delegate methods, links in the IB etc. stay intact, but exception is raised at the runtime.
The only solution is to clear all inks, related to tableview in the IB (outlet, datasource, delegate) and make them again.
If anyone is doing Unit Testing on a tableView and you're wondering why this error is appearing, just make sure that if you're using a text fixture, you must declare the system under test (SUT) in the setUp function correctly otherwise this error will keep coming up. It is also crucial you call loadViewIfNeeded() so the outlets between your code and storyboard are connected.
override func setUp() {
super.setUp()
let storyboard = UIStoryboard(name: "Main", bundle: nil)
sutSearch = storyboard.instantiateViewController(identifier:String(describing: SearchTableViewController.self))
sutSearch.loadViewIfNeeded() // To make sure your outlets are connected.
}
In the “Subclass of” field, select UITableViewController.
The class title changes to xxxxTableViewController. Leave that as is.
Make sure the “Also create XIB file” option is selected.
Make sure you have the identifier in the attributes filled out with your cell identifier
I was also struggling with the same problem. I had actually deleted the class and rebuilt it. Someone, the storyboard had dropped the link between prototype cell and the identifier.
I deleted the identifier name and re-typed the identifier name again.
It worked.
If the classic solutions (register identifier for class in code or IB) do not work: try to relaunch Xcode, turns out my storyboard stopped saving edits I was made, including setting the reuse identifier.
My dynamic tableview was working properly, with cell identifier set on the Storyboard and in dequeueReusableCell(withIdentifier:.
I then switched the UITableView content from Dynamic Prototypes to Static Cells.
Running the app immediately caused the error, although the cell's identifier was still set to the same value on the Storyboard.
For a static table view, you must register the cell identifier outside the Storyboard:
tableView.register(EntryNutritionCell.self, forCellReuseIdentifier: "Cell")
or, comment out or remove cellForRowAtIndexPath: entirely. This function isn't really used by the Static table view, but is still called(?) and causes the crash:
// override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
// let cell = tableView.dequeueReusableCell(withIdentifier: "Cell", for: indexPath)
// return cell
// }
'Table View Cell' identifier must match the class identifier.
ex: if your 'Table View Cell' identifier is named "myCellId", then your code should be:
let myCell = tableView.dequeueReusableCell(withIdentifier: "myCellId", for: indexPath).
Also, after hours of troubleshooting i realized that having a GestureRecognizer class in my didLoad() was not allowing me to click table cells. so removing all 'hide keyboard' functionality from didLoad() and other extra code solved it for me.
I was struggling with the same problem. i have already check my reusableCell Identifier it was same as in my code. I deleted line of my code
"let Cell = tableView.dequeueReusableCell(withIdentifier: "CELL", for: indexPath)"
clean build
and write it again!
It worked.