I have a table view that is rendering some static data into a UITableView but occasionally when running on a physical device the data is replaced with ? (see screenshot). I have listed the code below if anyone has an idea why this is occurring?
Here is the code for the table view
import UIKit
class OvenViewController: UIViewController {
#IBOutlet weak var tableView: UITableView!
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view.
}
}
extension OvenViewController : UITableViewDataSource,UITableViewDelegate{
func numberOfSections(in tableView: UITableView) -> Int {
return 1
}
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return GridData.ovenTempConvArray.count
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: OvenCell.className, for: indexPath) as! OvenCell
let data = GridData.ovenTempConvArray[indexPath.row]
cell.lblFTemp.text = "\(data["f"] ?? "") F"
cell.lblCTemp.text = "\(data["c"] ?? "") C"
cell.lblGasMark.text = data["gm"]
return cell
}
func tableView(_ tableView: UITableView, heightForRowAt indexPath: IndexPath) -> CGFloat {
return UITableView.automaticDimension
}
}
Related
I'm getting this error message in my table view controller class
value of uitableviewcell has no member delegate
Here is an image of the error.
Is there anything that should be changed in my code?
import UIKit
class TViewController: UIViewController,UITableViewDelegate,UITableViewDataSource {
#IBOutlet weak var Tviews: UITableViewCell!
let contacts:[[String]] = [
["Elon Musk", "+1-201-3141-5926"],
["Bill Gates", "+1-202-5358-9793"],
["Tim Cook", "+1-203-2384-6264"],
["Richard Branson", "+1-204-3383-2795"],
["Jeff Bezos", "+1-205-0288-4197"],
["Warren Buffet", "+1-206-1693-9937"],
["The Zuck", "+1-207-5105-8209"],
["Carlos Slim", "+1-208-7494-4592"],
]
override func viewDidLoad() {
super.viewDidLoad()
Tviews.delegate = self
Tviews.datasource = self
// Do any additional setup after loading the view.
}
func numberOfSections(in tableView: UITableView) -> Int {
return 1
}
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return contacts.count
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "tableViews", for: indexPath)
print("\(#function) --- section = \(indexPath.section), row = \(indexPath.row)")
cell.textLabel?.text = contacts[indexPath.row][0]
return cell
}
You should assign your delegate and data source to your table view instance, and not your table view cell.
In order to do that, create an outlet link with your table view in the TViewController file and then edit your code like this:
import UIKit
class TViewController: UIViewController,UITableViewDelegate,UITableViewDataSource {
#IBOutlet weak var tableView: UITableView!
let contacts:[[String]] = [
["Elon Musk", "+1-201-3141-5926"],
["Bill Gates", "+1-202-5358-9793"],
["Tim Cook", "+1-203-2384-6264"],
["Richard Branson", "+1-204-3383-2795"],
["Jeff Bezos", "+1-205-0288-4197"],
["Warren Buffet", "+1-206-1693-9937"],
["The Zuck", "+1-207-5105-8209"],
["Carlos Slim", "+1-208-7494-4592"],
]
override func viewDidLoad() {
super.viewDidLoad()
tableView.delegate = self
tableView.datasource = self
}
func numberOfSections(in tableView: UITableView) -> Int {
return 1
}
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return contacts.count
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "<your-table-view-cell-id>", for: indexPath) as! YourTableViewCell
cell.textLabel?.text = contacts[indexPath.row][0]
return cell
}
}
So I have two table views. MainTableView and SecondaryTableView, The MainTableView has empty rows with no text. A Table view cell is configured though. These rows have the option to delete. The SecondaryTableView rows also have an editing style in which I am using to ADD the selected row into the MainTableView rows.
class MainVC: UIViewController,UITableViewDataSource,UITableViewDelegate {
#IBOutlet var mycartableview: UITableView!
var passedcar = String()
override func viewDidLoad() {
super.viewDidLoad()
mycartableview.tableFooterView = UIView(frame: CGRect.zero)
}
var diynames: [String] = ["a","b","c"]
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return diynames.count
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let diyname = diynames[indexPath.row]
let cell = tableView.dequeueReusableCell(withIdentifier: "mycarcell") as! mycarcell
cell.mycartitle.text = diyname
return cell
}
func tableView(_ tableView: UITableView, canEditRowAt indexPath: IndexPath) -> Bool {
return true
}
func tableView(_ tableView: UITableView, commit editingStyle: UITableViewCell.EditingStyle, forRowAt indexPath: IndexPath) {
if editingStyle == .delete{
diynames.remove(at: indexPath.row)
tableView.beginUpdates()
tableView.deleteRows(at: [indexPath], with: .fade)
tableView.endUpdates()
}
}
SecondaryVC code:
class MainVC: UIViewController, UITableViewDelegate, UITableViewDataSource{
let names = ["aa","ba","ca","da","ea",]
#IBOutlet var tableview: UITableView!
#IBOutlet var slctedcar: UILabel!
override func viewDidLoad() {
super.viewDidLoad()
self.tableview.backgroundColor = .white
// Do any additional setup after loading the view.
}
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return names.count
return names.count
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "diylistcell") as! diylistcellTableViewCell
cell.diytitle.text = names[indexPath.row]
return cell
}
func tableView(_ tableView: UITableView, canEditRowAt indexPath: IndexPath) -> Bool {
return true
}
func tableView(_ tableView: UITableView, editActionsForRowAt indexPath: IndexPath) -> [UITableViewRowAction]? {
let addbutton = UITableViewRowAction(style: .normal, title: "Add") { (rowAction, indexpath
) in
print("Add clicked")
let mycarvc = MyCarViewController()
mycarvc.diynames.append(contentsOf: self.hcdiynames)
let hcindexpath = IndexPath(row: mycarvc.diynames.count - 1, section: 0)
mycarvc.mycartableview.insertRows(at: [hcindexpath], with: .automatic) //this is where the error occurs. Thread 1: Fatal error: Unexpectedly found nil while implicitly unwrapping an Optional value
mycarvc.mycartableview.endUpdates()
}
addbutton.backgroundColor = UIColor.darkGray
return [addbutton]
}
Clear Image of Error
That's where my pain is coming from. As you could see in the picture above the highlighted area it says that my array coming from the main vc is a count of 8. That checks out completely because the original array has 3 and I am appending 5 new ones. The error implicitly found nil has left me clueless in this scenario. If anybody has any suggestions on how to fix this problem it would be highly appreciated, thank you .
This is a common error when you try to transfer data between VC , I usually create 1 variable which will store what I want and after in the viewDidLoad() I give the value of this variable to what I really want , IN your code the equivalent is
class MainVC: UIViewController,UITableViewDataSource,UITableViewDelegate {
#IBOutlet var mycartableview: UITableView!
var passedcar = String()
// I JUST CREATED THE VARIABLE WHICH WILL HOLD OUR VALUES
var diynamesContainer = [String]()
///////////////////
var diynames: [String] = ["a","b","c"]
override func viewDidLoad() {
super.viewDidLoad()
mycartableview.tableFooterView = UIView(frame: CGRect.zero)
// I ADD TO OUR ARRAY THE VALUE OF THE diynamesContainer
diynames.append(contentsOf: diynamesContainer)
//////////////////
}
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return diynames.count
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let diyname = diynames[indexPath.row]
let cell = tableView.dequeueReusableCell(withIdentifier: "mycarcell") as! mycarcell
cell.mycartitle.text = diyname
return cell
}
func tableView(_ tableView: UITableView, canEditRowAt indexPath: IndexPath) -> Bool {
return true
}
func tableView(_ tableView: UITableView, commit editingStyle: UITableViewCell.EditingStyle, forRowAt indexPath: IndexPath) {
if editingStyle == .delete{
diynames.remove(at: indexPath.row)
tableView.beginUpdates()
tableView.deleteRows(at: [indexPath], with: .fade)
tableView.endUpdates()
}
}
/*
// MARK: - Navigation
and in our main vc you replace
let mycarvc = MyCarViewController()
mycarvc.diynames.append(contentsOf: self.hcdiynames)
by
let mycarvc = MyCarViewController()
mycarvc.diynamesContainer = self.hcdiynames
Try to run your code, the error will go away
I want execute a code when user tap on tableViewCell, this is the code:
import UIKit
import MediaPlayer
class ViewController: UIViewController, UITableViewDataSource {
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return titolo.count
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "cellReuseIdentifier")!
let text1 = titolo[indexPath.row]
let text2 = genere[indexPath.row]
cell.textLabel?.text = text1
cell.detailTextLabel?.text = text2
return cell
}
func numberOfSections(in tableView: UITableView) -> Int {
return 1
}
func tableView(tableView: UITableView, didSelectRowAtIndexPath indexPath: NSIndexPath) {
print("test tap cell")
}
#IBOutlet weak var tableView: UITableView!
let mediaItems = MPMediaQuery.songs().items
let musicPlayer = MPMusicPlayerApplicationController.applicationQueuePlayer
...
This function not work:
func tableView(tableView: UITableView, didSelectRowAtIndexPath indexPath: NSIndexPath) {
print("test tap cell")
}
"test tap cell" does not appear in the console.
You need to set delegate and dataSource and implement didSelectRowAt correctly
class ViewController: UIViewController , UITableViewDelegate, UITableViewDataSource {
#IBOutlet weak var tableView: UITableView!
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view.
self.tableView.delegate = self
self.tableView.dataSource = self
}
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return titolo.count
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "cellReuseIdentifier")!
cell.textLabel?.text = text1
cell.detailTextLabel?.text = text2
return cell
}
func numberOfSections(in tableView: UITableView) -> Int {
return 1
}
func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
print("test tap cell")
}
}
I am trying to get my tableView to show content in its cells, but it doesn't and I don't know why.
Here is the code. I also have connected the table view to the viewcontroller through dataSource and delegate in the storyboard, so that's why there are not typed in the viewDidLoad() method.
class ViewController: UIViewController, MKMapViewDelegate, UITableViewDelegate, UITableViewDataSource {
#IBOutlet weak var tableView: UITableView!
override func viewDidLoad() {
super.viewDidLoad()
wordsArray = [Words(sectionName: "Example section", usedWords: ["aaaaa", "aaaaa", "aaaaa"])]
tableView.alpha = 1
}
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return favCapitals.count
}
struct Words {
var sectionName: String! = ""
var usedWords: [String]! = []
}
var wordsArray: [Words] = []
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "cell", for: indexPath) as UITableViewCell
cell.textLabel?.text = wordsArray[indexPath.section].usedWords[indexPath.row]
cell.textLabel?.textColor = .black
return cell
}
func tableView(_ tableView: UITableView, titleForHeaderInSection section: Int) -> String? {
let sectionName = "Favourite Capitals"
return sectionName
}
You will need to call the following methods before it listens to cellForRowAt:
override func numberOfSections(in tableView: UITableView) -> Int {
return 1
}
override func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return 1
}
another common problem is that the frame of the table is not set (e.g. inside a UITableViewCell, with automatic dimensions). The table requires a frame before it gets cells.
You can use tableView.reloadData() in the viewDidLoad Method.
I have a table view with different sections and for each section it has different prototype cells. I have created the prototype cell in storyboard but I could not make more than one cell in cellForRowAtIndexPath. I have attached the whole code for reference.
This is my storyboard design
This is the final output screen which it should look like
import UIKit
class PlacePeopleViewController: UIViewController, UITableViewDataSource, UITableViewDelegate {
#IBOutlet weak var friendlistTableView: UITableView!
var sectionHead = ["Friends", "Others"]
override func viewDidLoad() {
super.viewDidLoad()
friendlistTableView.delegate = self
friendlistTableView.dataSource = self
// Do any additional setup after loading the view.
}
// MARK: - tableview datasource & delegate
func numberOfSections(in tableView: UITableView) -> Int {
return sectionHead.count
}
func tableView(_ tableView: UITableView, titleForHeaderInSection section: Int) -> String? {
return self.sectionHead[section]
}
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
if section == 0 {
return 5
}else {
return 10
}
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "cell1") as! RecentVizzTableViewCell
cell.placeName.text = "poland"
cell.placeAddress.text = "Simon Albania"
return cell
}
func tableView(_ tableView: UITableView, heightForRowAt indexPath: IndexPath) -> CGFloat {
return 79
}
func tableView(_ tableView: UITableView, heightForFooterInSection section: Int) -> CGFloat {
return 15
}
}
Note : You can do this using only one cell. just hide/show the connect Button by checking some condition.
If you want to use different cells for different sections, inside your cellForRowAt indexPath method return your cells based on your section like below .
switch indexPath.section {
case 0:
let cell = tableView.dequeueReusableCell(withIdentifier: "cell1") as! RecentVizzTableViewCellOne
return cell
default:
let defaultcell = tableView.dequeueReusableCell(withIdentifier: "defaultcell") as! RecentVizzTableViewCellDefatult
return defaultcell
}
hope this will help to you. good luck.