Swift 'unable to dequeue a cell with identifier intervalCellIdentifier - swift

Question

I recently started programming using swift(swift newbie! :b)
got an error and have no idea how to fix it :c
this is the code of viewcontroller.swift !
import UIKit
class ViewController: UIViewController, UIPickerViewDelegate, UIPickerViewDataSource, UITableViewDataSource,UITableViewDelegate {
#IBOutlet weak var picker1: UIPickerView!
#IBOutlet weak var keySelect: UITableView!
var Array = ["2", "3", "4"]
#IBOutlet weak var picker1label: UILabel!
#IBOutlet weak var keyselectView: UILabel!
#IBOutlet weak var keylabel: UIButton!
let intervalCellIdentifier = "intervalCellIdentifier"
var intervalNames = ["Q", "W", "E", "R", "T", "Y"]
let limit = 5
var answer1 = 0
override func viewDidLoad() {
super.viewDidLoad()
picker1.delegate = self
picker1.dataSource = self
//edited
keySelect.delegate = self
keySelect.dataSource = self
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
func pickerView(pickerView: UIPickerView, titleForRow row: Int, forComponent component: Int) -> String! {
return Array[row]
}
func pickerView(pickerView: UIPickerView, numberOfRowsInComponent component: Int) -> Int {
return Array.count
}
func numberOfComponentsInPickerView(pickerView: UIPickerView) -> Int {
return 1
}
#IBAction func submit1(sender: AnyObject) {
if(answer1 == 0) {
picker1label.text = "2"
}
else if(answer1 == 1) {
picker1label.text = "3"
}
else {
picker1label.text = "4"
}
}
func pickerView(pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int) {
answer1 = row
}
func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return intervalNames.count
}
func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) ->UITableViewCell {
let cell = tableView.dequeueReusableCellWithIdentifier(intervalCellIdentifier,forIndexPath: indexPath) as UITableViewCell
cell.accessoryType = .None
cell.textLabel?.text = intervalNames[indexPath.row]
return cell
}
//MARK: - UITableViewDelegate
func tableView(tableView: UITableView, willSelectRowAtIndexPath indexPath: NSIndexPath) -> NSIndexPath? {
if let sr = tableView.indexPathsForSelectedRows {
if sr.count == limit {
let alertController = UIAlertController(title: "Oops", message:
"You are limited to \(limit) selections", preferredStyle: .Alert)
alertController.addAction(UIAlertAction(title: "OK", style: .Default, handler: {action in
}))
self.presentViewController(alertController, animated: true, completion: nil)
return nil
}
}
return indexPath
}
func tableView(tableView: UITableView, didSelectRowAtIndexPath indexPath: NSIndexPath) {
print("selected \(intervalNames[indexPath.row])")
if let cell = tableView.cellForRowAtIndexPath(indexPath) {
if cell.selected {
cell.accessoryType = .Checkmark
}
}
if let sr = tableView.indexPathsForSelectedRows {
print("didDeselectRowAtIndexPath selected rows:\(sr)")
}
}
func tableView(tableView: UITableView, didDeselectRowAtIndexPath indexPath: NSIndexPath) {
print("deselected \(intervalNames[indexPath.row])")
if let cell = tableView.cellForRowAtIndexPath(indexPath) {
cell.accessoryType = .None
}
if let sr = tableView.indexPathsForSelectedRows {
print("didDeselectRowAtIndexPath selected rows:\(sr)")
}
}
}
2016-07-28 23:08:29.868 customkeyboard[60865:1611607] * Assertion failure in -[UITableView dequeueReusableCellWithIdentifier:forIndexPath:], /BuildRoot/Library/Caches/com.apple.xbs/Sources/UIKit_Sim/UIKit-3512.29.5/UITableView.m:6547
2016-07-28 23:08:29.945 customkeyboard[60865:1611607] * Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: 'unable to dequeue a cell with identifier intervalCellIdentifier - must register a nib or a class for the identifier or connect a prototype cell in a storyboard'
this is error explanation(?)
help me :3

Answer 1

1. With XIB file
You have to register the cell to table first, may be in viewDidLoad, as:
let nib = UINib(nibName: "CustomCell", bundle: NSBundle.mainBundle())
tableView.registerNib(nib, forCellReuseIdentifier: "CustomCellIdentifier")
This is applicable if we are using a custom cell with .xib file.
2. Without XIB file
And here is a solution if we are not creating separate .xib file for custom cell:
We need to create dynamic prototype for cell in table view as:
Then we need to provide class name and reuse identifier for our custom cell as:
Here, no need to register class or nib!
Here is the cellForRowAtIndexPath implementation:
override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
// Configure the cell...
let cell = tableView.dequeueReusableCellWithIdentifier("CustomTableViewCellId", forIndexPath: indexPath) as! CustomTableViewCell
cell.setCellIndexLabel(indexPath.row)
return cell
}
This implementation will be same for both the above solutions.
3. Only Class Implementation
Without XIB, without Dynamic Prototype
Here is the custom cell without any XIB or Dynamic Prototype:
class WithoutNibCustomTableViewCell: UITableViewCell {
override init(style: UITableViewCellStyle, reuseIdentifier: String?) {
super.init(style: style, reuseIdentifier: reuseIdentifier)
//do custom initialisation here, if any
}
required init?(coder aDecoder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
override func awakeFromNib() {
super.awakeFromNib()
// Initialization code
}
override func setSelected(selected: Bool, animated: Bool) {
super.setSelected(selected, animated: animated)
// Configure the view for the selected state
}
class func identifier() -> String {
return "WithoutNibCustomTableViewCellId"
}
//MARK: Public Methods
func setCellIndexLabel(index: Int) {
let customLbl = UILabel(frame: CGRectMake(0, 0, 100, 40))
customLbl.text = String(index)
contentView.addSubview(customLbl)
}
}
Then, in table view, we need to register cell class as:
tableView!.registerClass(WithoutNibCustomTableViewCell.classForCoder(), forCellReuseIdentifier: WithoutNibCustomTableViewCell.identifier())
cellForRowAtIndexPath also same as above, like:
let cell = tableView.dequeueReusableCellWithIdentifier(WithoutNibCustomTableViewCell.identifier(), forIndexPath: indexPath) as! WithoutNibCustomTableViewCell
cell.setCellIndexLabel(indexPath.row)
return cell

Answer 2

in cellForRow change this :
let cell = tableView.dequeueReusableCellWithIdentifier(intervalCellIdentifier,forIndexPath: indexPath) as UITableViewCell by
let cell = tableView.dequeueReusableCellWithIdentifier(intervalCellIdentifier,forIndexPath: indexPath) as your cell class name .

Answer 3

I published a pod that will make your life easier while working with cells:
https://cocoapods.org/pods/CellRegistration
It simplifies the API to just one-line:
let : MyCustomCell = tableView.dequeueReusableCell(forIndexPath: indexPath)