Show TableView in Swift Playgrounds for iPad - ios

Everything works fine except the last line where I try to show the tableView in live view does not work: PlaygroundPage.current.liveView = controller
I can't figure out what I'm getting wrong?
import UIKit
import PlaygroundSupport
import Foundation
class TableViewController: UITableViewController {
let tableData = ["Matthew", "Mark", "Luke", "John"]
override func viewDidLoad() {
super.viewDidLoad()
print("Hello Matt")
}
override func numberOfSections(in tableView: UITableView) -> Int {
return 1
}
override func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return tableData.count
}
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
var cell = tableView.dequeueReusableCell(withIdentifier: "cell", for: indexPath) as UITableViewCell
cell.textLabel?.text = tableData[indexPath.row]
return cell
}
}
let controller = TableViewController()
PlaygroundPage.current.liveView = controller


I think you forgot to register the table view cell class in viewDidLoad()
override func viewDidLoad() {
super.viewDidLoad()
tableView.register(UITableViewCell.self, forCellReuseIdentifier: "cell")
}


In func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath), add one line to the top of the function:
tableView.register(UITableViewCell.self, forCellReuseIdentifier: "cell")
Like this:
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
tableView.register(UITableViewCell.self, forCellReuseIdentifier: "cell")
var cell = tableView.dequeueReusableCell(withIdentifier: "cell", for: indexPath) as UITableViewCell
cell.textLabel?.text = tableData[indexPath.row]
return cell
}

Related

custom tableview cell doesn't appear

import UIKit
class anasayfaVC: UIViewController, UITableViewDataSource , UITableViewDelegate {
#IBOutlet weak var tableView1: UITableView!
override func viewDidLoad() {
super.viewDidLoad()
tableView1.delegate = self
tableView1.dataSource = self
}
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return 5
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "Cell", for: indexPath) as! FeedCell
cell.deneme.image = UIImage(named: "naruto")
return cell
}
}

did you register your tableview as
tableView.register(UINib(nibName: "FeedCell", bundle: nil), forCellReuseIdentifier: "Cell") ?

How to show info on table view

Im trying to load a array of strings in a table view but the view does not recognize the array.
I have an array called Playlists (declared as global on ThirdViewController) with objects from class Playlist. When I use it on every other table view I can access every object and use it on the table view (I'm using it on ThirdViewController), but on AddToPlaylist view I can't use it. I think I'm using correctly the cells and func for table views.
This happens when I press the button "Añadir" on player view. It should load the table view with the array info.
Here is the project (develop branch): tree/develop
import UIKit
class AddToPlaylist: UIViewController, UITableViewDelegate, UITableViewDataSource{
#IBOutlet weak var myTableViewPlaylist: UITableView!
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return Playlists.count
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "hola", for: indexPath)
cell.textLabel?.text = Playlists[indexPath.row].name
return cell
}
func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
Playlists[indexPath.row].songs.append(songName)
performSegue(withIdentifier: "addedSong", sender: self)
}
override func viewDidLoad() {
super.viewDidLoad()
myTableViewPlaylist.delegate = self
myTableViewPlaylist.dataSource = self
myTableViewPlaylist.reloadData()
}
}
Here is the declaration of Playlists array:
import UIKit
import AVFoundation
var favorites:[String] = []
var Playlists:[Playlist] = []
var selecPlaylist = 0
var firstOpen2 = true
class ThirdViewController: UIViewController, UITableViewDelegate, UITableViewDataSource {
#IBOutlet weak var myTableView2: UITableView!
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
//print(Playlists.count)
return Playlists.count
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = UITableViewCell(style: .default, reuseIdentifier: "cell")
cell.textLabel?.text = Playlists[indexPath.row].name
return cell
}
func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
selecPlaylist = indexPath.row
performSegue(withIdentifier: "segue", sender: self)
}
override func viewDidLoad() {
super.viewDidLoad()
myTableView2.delegate = self
myTableView2.dataSource = self
if firstOpen2{
crear()
firstOpen2 = false
}
myTableView2.reloadData()
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
func crear(){
let pl1 = Playlist(name: "Prueba")
pl1?.addSong(song: songs[0])
Playlists.append(pl1!)
let pl2 = Playlist(name: "Prueba2")
pl2?.addSong(song: songs[1])
Playlists.append(pl2!)
}
}

let cell = tableView.dequeueReusableCell(withIdentifier: "yourIdentifier") as! UITableViewCell
cell.textLabel?.text = Playlists[indexPath.row].name
return cell

UITableViewCell gets deleted after scrolling

I am trying to create a ToDo list application. For this application, I require a custom UITableViewCell. I am trying to use my custom cell, however, when I run the app and try to scroll through the table view all the cells get deleted.
This is my code:
class ToDoListVC: UIViewController, UITableViewDataSource, UITableViewDelegate {
#IBOutlet weak var tableView: UITableView!
override func viewDidLoad() {
super.viewDidLoad()
let nib = UINib(nibName: "TodoCell", bundle: nil)
tableView.register(nib, forCellReuseIdentifier: "customCell")
tableView.delegate = self
tableView.dataSource = self
}
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return HomeVC.ToDoEvents.count
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell{
let cell = tableView.dequeueReusableCell(withIdentifier: "customCell") as! TodoCell
let eventName = HomeVC.ToDoEvents[indexPath.row].name
let eventTime = HomeVC.ToDoEvents[indexPath.row].time
let completion = HomeVC.ToDoEvents[indexPath.row].isComplete
cell.initialize(task: eventName!, length: eventTime!, completion: completion!)
return cell
}
func tableView(_ tableView: UITableView, heightForRowAt indexPath: IndexPath) -> CGFloat {
return 70
}
}
I am not sure what I am doing wrong. I went through some of the other threads, however, none of them solved my problem.

Data loading issue in Table View in IOS

I have a table view controller in my view controller. When I give it static number of rows and cell for row index method name it shows nothing to me in the table view. I have also reload the table view but it isn't showing I don't know why is it so,
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return messages.count
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = UITableViewCell (style: .subtitle, reuseIdentifier: "cellID")
let message = messages[indexPath.row]
cell.textLabel?.text = message.text
return cell
}

Recheck if u have set
tableView.delegate = self
tableView.datasource = self
Also put a breakpoint on cellForRowAtIndexpath to check if code runs through the block.
Also Recheck the cellIdentifier (cellID) is correct or not.

class ViewController:UIViewController,UITableViewDataSource,UITableViewDelegate {
//Getting the reference variables of storyboard
#IBOutlet weak var tableView:UITableView!
var messages = [String]()
override func viewDidLoad() {
super.viewDidLoad()
//Add some packages
messages.append("Super")
messages.append("Free ")
messages.append("Miscellaneous")
messages.append("All ")
tableView.datasource = self
tableView.delegate = self
}
func numberOfSections(in tableView: UITableView) -> Int {
return 1
}
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return messages.count
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = UITableViewCell (style: .subtitle, reuseIdentifier: "cellID")
let message = messages[indexPath.row]
cell.textLabel?.text = message.text
return cell
}
}

Use this . This one works for me
class yourViewController: UIViewController,UITableViewDataSource,UITableViewDelegate {
#IBOutlet weak var tableView:UITableView!
override func viewDidLoad() {
super.viewDidLoad()
tableView.datasource = self
tableView.delegate = self
}
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return messages.count
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell=tableView.dequeueReusableCell(withIdentifier: "cellID",for : indexPath)
let message = messages[indexPath.row]
cell.textLabel?.text = message.text
return (cell)
}
}

Create UITableView programmatically in Swift

I try to implement UITableView programmatically without use of xib or Storyboards. This is my code:
ViewController.swift
import UIKit
class ViewController: UIViewController {
override func viewDidLoad() {
super.viewDidLoad()
let table: UITableViewController = MyTableViewController()
let tableView: UITableView = UITableView()
tableView.frame = CGRect(x: 10, y: 10, width: 100, height: 500)
tableView.dataSource = table
tableView.delegate = table
self.view.addSubview(tableView)
}
}
MyTableViewController.swift
import UIKit
class MyTableViewController: UITableViewController {
override func numberOfSectionsInTableView(tableView: UITableView) -> Int {
NSLog("sections")
return 2
}
override func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
NSLog("rows")
return 3
}
override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
NSLog("get cell")
let cell = UITableViewCell(style: UITableViewCellStyle.Value1, reuseIdentifier: "Cell")
cell.textLabel!.text = "foo"
return cell
}
}
But when I run app, all I get is empty table. In log I see a few lines of sections and rows, but no get cell. How can I fix this code to get table with 6 lines of foo text?

Note: As you mentioned you just started programming in Swift. I created a tableView programmatically. Copy and paste below code into your viewController and run the project...
import UIKit
class ViewController: UIViewController, UITableViewDelegate, UITableViewDataSource {
private let myArray: NSArray = ["First","Second","Third"]
private var myTableView: UITableView!
override func viewDidLoad() {
super.viewDidLoad()
let barHeight: CGFloat = UIApplication.shared.statusBarFrame.size.height
let displayWidth: CGFloat = self.view.frame.width
let displayHeight: CGFloat = self.view.frame.height
myTableView = UITableView(frame: CGRect(x: 0, y: barHeight, width: displayWidth, height: displayHeight - barHeight))
myTableView.register(UITableViewCell.self, forCellReuseIdentifier: "MyCell")
myTableView.dataSource = self
myTableView.delegate = self
self.view.addSubview(myTableView)
}
func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
print("Num: \(indexPath.row)")
print("Value: \(myArray[indexPath.row])")
}
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return myArray.count
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "MyCell", for: indexPath as IndexPath)
cell.textLabel!.text = "\(myArray[indexPath.row])"
return cell
}
}
Output:

Updated for Swift 3
Option 1:
import UIKit
//
// MARK :- TableViewController
//
class TableViewController: UITableViewController {
private let headerId = "headerId"
private let footerId = "footerId"
private let cellId = "cellId"
//
// MARK :- HEADER
//
override func tableView(_ tableView: UITableView, heightForHeaderInSection section: Int) -> CGFloat {
return 150
}
override func tableView(_ tableView: UITableView, viewForHeaderInSection section: Int) -> UIView? {
let header = tableView.dequeueReusableHeaderFooterView(withIdentifier: headerId) as! CustomTableViewHeader
return header
}
//
// MARK :- FOOTER
//
override func tableView(_ tableView: UITableView, heightForFooterInSection section: Int) -> CGFloat {
return 150
}
override func tableView(_ tableView: UITableView, viewForFooterInSection section: Int) -> UIView? {
let footer = tableView.dequeueReusableHeaderFooterView(withIdentifier: footerId) as! CustomTableViewFooter
return footer
}
//
// MARK :- CELL
//
override func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return 1
}
override func tableView(_ tableView: UITableView, heightForRowAt indexPath: IndexPath) -> CGFloat {
return 150
}
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: cellId, for: indexPath) as! CustomTableCell
return cell
}
override func viewDidLoad() {
super.viewDidLoad()
title = "TableView Demo"
view.backgroundColor = .white
setupTableView()
}
func setupTableView() {
tableView.backgroundColor = .lightGray
tableView.register(CustomTableViewHeader.self, forHeaderFooterViewReuseIdentifier: headerId)
tableView.register(CustomTableViewFooter.self, forHeaderFooterViewReuseIdentifier: footerId)
tableView.register(CustomTableCell.self, forCellReuseIdentifier: cellId)
}
}
//
// MARK :- HEADER
//
class CustomTableViewHeader: UITableViewHeaderFooterView {
override init(reuseIdentifier: String?) {
super.init(reuseIdentifier: reuseIdentifier)
contentView.backgroundColor = .orange
}
required init?(coder aDecoder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
}
//
// MARK :- FOOTER
//
class CustomTableViewFooter: UITableViewHeaderFooterView {
override init(reuseIdentifier: String?) {
super.init(reuseIdentifier: reuseIdentifier)
contentView.backgroundColor = .green
}
required init?(coder aDecoder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
}
//
// MARK :- CELL
//
class CustomTableCell: UITableViewCell {
override init(style: UITableViewCellStyle, reuseIdentifier: String?) {
super.init(style: style, reuseIdentifier: reuseIdentifier)
contentView.backgroundColor = .white
}
required init?(coder aDecoder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
}
Option 2: replace above Option 1 TableViewController with this class
import UIKit
//
// MARK :- ViewController
//
class ViewController: UIViewController, UITableViewDelegate, UITableViewDataSource {
private let headerId = "headerId"
private let footerId = "footerId"
private let cellId = "cellId"
lazy var tableView: UITableView = {
let tv = UITableView(frame: .zero, style: .plain)
tv.translatesAutoresizingMaskIntoConstraints = false
tv.backgroundColor = .lightGray
tv.delegate = self
tv.dataSource = self
tv.register(CustomTableViewHeader.self, forHeaderFooterViewReuseIdentifier: self.headerId)
tv.register(CustomTableViewFooter.self, forHeaderFooterViewReuseIdentifier: self.footerId)
tv.register(CustomTableCell.self, forCellReuseIdentifier: self.cellId)
return tv
}()
//
// MARK :- HEADER
//
func tableView(_ tableView: UITableView, heightForHeaderInSection section: Int) -> CGFloat {
return 150
}
func tableView(_ tableView: UITableView, viewForHeaderInSection section: Int) -> UIView? {
let header = tableView.dequeueReusableHeaderFooterView(withIdentifier: headerId) as! CustomTableViewHeader
return header
}
//
// MARK :- FOOTER
//
func tableView(_ tableView: UITableView, heightForFooterInSection section: Int) -> CGFloat {
return 150
}
func tableView(_ tableView: UITableView, viewForFooterInSection section: Int) -> UIView? {
let footer = tableView.dequeueReusableHeaderFooterView(withIdentifier: footerId) as! CustomTableViewFooter
return footer
}
//
// MARK :- CELL
//
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return 1
}
func tableView(_ tableView: UITableView, heightForRowAt indexPath: IndexPath) -> CGFloat {
return 150
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: cellId, for: indexPath) as! CustomTableCell
return cell
}
override func viewDidLoad() {
super.viewDidLoad()
title = "TableView Demo"
view.backgroundColor = .white
view.addSubview(tableView)
setupAutoLayout()
}
func setupAutoLayout() {
tableView.leftAnchor.constraint(equalTo: view.leftAnchor).isActive = true
tableView.rightAnchor.constraint(equalTo: view.rightAnchor).isActive = true
tableView.topAnchor.constraint(equalTo: view.topAnchor).isActive = true
tableView.bottomAnchor.constraint(equalTo: view.bottomAnchor).isActive = true
}
}

Swift 4 compatible
Instead of adding a UITableView to your UIViewController, you should consider creating a UITableViewController and avoid setting up delegates:
class YourTVC: TableViewController {
override func viewDidLoad() {
super.viewDidLoad()
// setup custom cells if you use them
tableView.register(CustomTableViewCell.self, forCellReuseIdentifier: "yourCell")
}
// MARK: tableView
override func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return 3 // set to value needed
}
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "yourCell", for: indexPath) as! CustomTableViewCell
cell.textLabel?.text = "Cell at row \(indexPath.row)"
return cell
}
}

It makes no sense that you are using a UITableViewController as the data source and delegate for your view controller's table view. Your own view controller should be the table view's data source and delegate.
Since you seem to want a view controller with a table view that doesn't take up the entire view, move every thing to your view controller as follows:
ViewController.swift:
import UIKit
class ViewController: UIViewController, UITableViewDataSource, UITableViewDelegate {
override func viewDidLoad() {
super.viewDidLoad()
let tableView: UITableView = UITableView()
tableView.frame = CGRect(x: 10, y: 10, width: 100, height: 500)
tableView.dataSource = self
tableView.delegate = self
self.view.addSubview(tableView)
}
func numberOfSectionsInTableView(tableView: UITableView) -> Int {
NSLog("sections")
return 2
}
func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
NSLog("rows")
return 3
}
func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
NSLog("get cell")
let cell = UITableViewCell(style: UITableViewCellStyle.Value1, reuseIdentifier: "Cell")
cell.textLabel!.text = "foo"
return cell
}
}

You don't need to make a separate class for UITableView. Just in your ViewController class implement protocols of UITableViewDelegate and UITableViewDataSource and then implement delegate methods.
I think your code should be like
class ViewController: UIViewController , UITableViewDelegate , UITableViewDataSource {
override func viewDidLoad() {
super.viewDidLoad()
let table: UITableViewController = MyTableViewController()
let tableView: UITableView = UITableView()
tableView.frame = CGRect(x: 10, y: 10, width: 100, height: 500)
tableView.dataSource = table
tableView.delegate = table
self.view.addSubview(tableView)
}
override func numberOfSectionsInTableView(tableView: UITableView) -> Int {
NSLog("sections")
return 2
}
override func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
NSLog("rows")
return 3
}
override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
NSLog("get cell")
let cell = UITableViewCell(style: UITableViewCellStyle.Value1, reuseIdentifier: "Cell")
cell.textLabel!.text = "foo"
return cell
}
}
Tell us more info or show logs if you still face issue.

I had a similar issue in that the data would not populate for my programmatic UITableView. This was because I was using a delegate/dataSource without a strong reference. Once I kept a reference to it (I had one class implementing both UITableViewDataSource and UITableViewDelegate), the data was populated.

import UIKit
class ViewController: UITableViewController {
override func viewDidLoad() {
super.viewDidLoad()
tableView.register(TableCell.self, forCellReuseIdentifier: "cell")
}
override func numberOfSections(in tableView: UITableView) -> Int {
return 1
}
override func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return 10
}
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "cell", for: indexPath) as! TableCell
cell.nameLabel.text = "TableViewCell programtically"
cell.nameLabel.textAlignment = .center
cell.nameLabel.textColor = .white
return cell
}
override func tableView(_ tableView: UITableView, heightForRowAt indexPath: IndexPath) -> CGFloat {
return 100
}
}

Simple solution
import UIKit
class CustomTableViewController: UICollectionViewController {
override func viewDidLoad() {
super.viewDidLoad()
tableView.register(UITableViewCell.self, forCellReuseIdentifier: "Cell")
}
override func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return 10
}
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "Cell", for: indexPath as IndexPath)
cell.textLabel!.text = "\(indexPath.row)"
return cell
}
}

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