I've created a tableView with a registered Cell with reuseIdentifier as "cell". I've added this tableView to superview as subview.
private let tableView: UITableView = {
let table = UITableView()
table.register(UITableViewCell.self, forCellReuseIdentifier: "cell")
return table
}()
I've comforted the protocol functions for TableViewCellDelegate and DataSource as below. But still when I do run the app it only shows my tableView but not the cells which should write "Hello". Why this might be happening?
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return notifications.count
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let model = notifications[indexPath.row]
let cell = tableView.dequeueReusableCell(withIdentifier: "cell", for: indexPath)
cell.textLabel?.text = "Hello"
return cell
}
Do check with your notifications array is it empty or not if you are fetching it from api make sure to call tableView.reloadData()
have you added your tableView into view ?
Add code below in the ViewController and it should work
override func viewDidLoad() {
super.viewDidLoad()
tableView.dataSource = self
tableView.delegate = self
}
Related
I am new to SWIFT and trying to show some data into table view controller but when I press the button it shows the above error. Please correct me
import UIKit
var selectedPlace : Place!
class ShowPlaceTableTableViewController: UITableViewController {
var places : [Place]!
override func viewDidLoad()
{
super.viewDidLoad()
places = readPlaces()
}
// MARK: - Table view data source
override func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
// #warning Incomplete implementation, return the number of rows
return places.count
}
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "cell", for: indexPath) as! PlaceTableViewCell
cell.countryLabel.text = places[indexPath.row].country
cell.placeImageView.image = places[indexPath.row].picture
return cell
}
func readPlaces() -> [Place]
{
if UserDefaults.standard.object(forKey: "places") != nil
{
var data = UserDefaults.standard.object(forKey: "places") as! Data
let places = try! NSKeyedUnarchiver.unarchiveTopLevelObjectWithData(data) as! [Place]
return places
}else
{
return [Place]()
}
}
override func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
selectedPlace = places[indexPath.row]
performSegue(withIdentifier: "detailSegue", sender: self)
}
}
Is your PlaceTableViewCell inside it's own xib separately OR is it inside the storyboard itself? You must register either a cell class or a nib before you try to dequeue the cell from tableView.
If it's inside the storyboard, then you can register the subclass to work with it.
tableView.register(PlaceTableViewCell.self, forCellReuseIdentifier: "PlaceTableViewCell")
If it's inside it's own xib separately, then you can register the UINib to work with it.
tableView.register(UINib(nibName: "PlaceTableViewCell", bundle: nil), forCellReuseIdentifier: "PlaceTableViewCell")
These need to be called once only, you can place these calls inside viewDidLoad().
Now you can dequeue it like following -
let cell = tableView.dequeueReusableCell(withIdentifier: "PlaceTableViewCell") as! PlaceTableViewCell
Note : The reuseIdentifier must be same in following places -
storyboard (or xib)
at the time of registration tableView.register...
at the time of dequeue tableView.dequeue...
I have a tableView with 2 custom xib cells. I want to switch the custom cell when user tapped it also adjust the cell height. How do I achieve it? I tried to use container view but then the height would be the same. I want to know if it is possible to do it with two xib for tableView cell? Thank you.
var isContactView: Bool = true
override func viewDidLoad() {
super.viewDidLoad()
tableView.delegate = self
tableView.dataSource = self
tableView.register(UINib(nibName: "ContactTableViewCell", bundle: nil), forCellReuseIdentifier: "contactCell")
tableView.register(UINib(nibName: "DetailTableViewCell", bundle: nil), forCellReuseIdentifier: "detailCell")
}
func tableView(_ tableView: UITableView, heightForRowAt indexPath: IndexPath) -> CGFloat {
//if ContactTableViewCell return 40
//if DetailTableViewCell return 150
}
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return 1
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
//by default the cell view is ContactTableViewCell.
//When user tapped the cell it will change to DetailTableViewCell.
if isContactView {
let cell = tableView.dequeueReusableCell(withIdentifier: "contactCell", for: indexPath) as! ContactTableViewCell
//do something...
} else {
let cell = tableView.dequeueReusableCell(withIdentifier: "detailCell", for: indexPath) as! DetailTableViewCell
//do something...
}
return cell
}
func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
//not sure how to change the xib in here.
//if cell view is ContactTableViewCell
cell view = tableView.dequeueReusableCell(withIdentifier: "detailCell", for: indexPath) as! DetailTableViewCell
isContactView = false
tableView.reloadData()
//else
cell view = tableView.dequeueReusableCell(withIdentifier: "contactCell", for: indexPath) as! ContactTableViewCell
isContactView = true
tableView.reloadData()
}
There are 2 cases:
If there's just single cell to be viewed, then just put the following code in didSelect:
isContactView = !isContactView
tableView.reloadData()
If there are multiple cells in which the condition is to be applied. Please put a key in your data model.
For example:
testArr is the array of objects that you are displaying in tableview. Then keep a key, say isContactView in this model. And put the login based upon this key.
Like in case of cellForRow:
if testArr[indexpath.row].isContactView {
let cell = tableView.dequeueReusableCell(withIdentifier: "contactCell", for: indexPath) as! ContactTableViewCell
//do something...
} else {
let cell = tableView.dequeueReusableCell(withIdentifier: "detailCell", for: indexPath) as! DetailTableViewCell
//do something...
}
And in didselect:
isContactView = !testArr[indexPath.row].isContactView
I have this table view, that populates through Core Data. Everything looks fine, even when scrolling, until I press and hold any row - then that row distorts like in the second image below.
(source: staticflickr.com)
(source: staticflickr.com)
Here's the code to display the tableview
override func viewDidLoad() {
super.viewDidLoad()
animateBackground(colors)
tableView.delegate = self
tableView.dataSource = self
tableView.fetchData(fetchedResultsController as! NSFetchedResultsController<NSFetchRequestResult>)
self.tableView.tableFooterView = UIView(frame: .zero)
}
func numberOfSections(in tableView: UITableView) -> Int {
guard fetchedResultsController.sections?.count != nil else { return 0 }
return fetchedResultsController.sections!.count
}
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
guard fetchedResultsController.sections != nil else { return 0 }
let data = fetchedResultsController.sections![section]
return data.numberOfObjects
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "SkillCell", for: indexPath) as! SkillCell
configureCell(cell: cell, indexPath: indexPath as NSIndexPath)
return cell
}
func configureCell(cell: SkillCell, indexPath: NSIndexPath) {
let skill = fetchedResultsController.object(at: indexPath as IndexPath)
cell.skill = skill
}
func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) { }
}
From the code above, everything looks normal, yet this distortion occurs. Please help me to see why and how to stop it happening.
As the comment suggests, it's just a visual effect called selectionStyle of your UITableViewCell. Inside your cellForRowAt indexPath method, you can disable it like:
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "myCell") as! MyCell
cell.selectionStyle = .none // this removes the effect.
return cell
}
yes you should set tableView selection style to none.
1.Select the tableview in storyboard in the right panel set selection style to none.
or
2.in your tableview cellforrow method set
tableView.selectionstyle = none
I am trying to make a to-do list app and I am having trouble trying to add subtasks to my main to-do tasks. I have a button inside each table view cell, when this button is pressed I want it to add another table view cell that I can type and save a "subtask" on.
//set up tableView row amount
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return taskData.count
}
//set up what is in the tableView row
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
//This is for a main task
let cell = tableView.dequeueReusableCell(withIdentifier: "TaskCell", for: indexPath) as! CustomTableViewCell
cell.label.text = taskData[indexPath.row]
return cell
}
Use delegates to pass data from cells to your ViewController, and reload the tableView.
CustomTableViewCell:
protocol CustomTableViewCellDelegate: class {
func customTableViewCellButtonClicked(_ cell: CustomTableViewCell)
}
class CustomTableViewCell: UITableViewCell {
weak var delegate: CustomTableViewCellDelegate?
func buttonClicked() {
self.delegate?.customTableViewCellButtonClicked(self)
}
}
ViewController:
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "TaskCell", for: indexPath) as! CustomTableViewCell
cell.label.text = taskData[indexPath.row]
cell.delegate = self
return cell
}
func customTableViewCellButtonClicked(_ cell: CustomTableViewCell) {
// add the task you need from that cell to your tasks list.
taskData.append(....)
//reload your tableView
self.tableView.reloadData()
}
I have a UITableView.
I can select multiple cells make them highlighted.
But, whenever I reload App, the selected and highlighted state disappears.
I think I need to put some codes in 'viewDidAppear' and 'didSelectRowAt'. But I don't have any idea of specific codes.
What do I have to put in this syntax?
class ViewController: UIViewController, UITableViewDataSource, UITableViewDelegate {
override func viewDidAppear(_ animated: Bool) {
super.viewDidAppear(animated)
tableView.reloadData()
}
func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
}
}
I recommend u add to dataSource item field selected, and in method cellForRowAtindexPath configure by your dataSource items.
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
guard let cellClass = (self.cellClass(for: indexPath) ?? self.cellClasses.first) else { return UITableViewCell() }
let cell = tableView.dequeueReusableCell(withIdentifier: cellClass.identifier, for: indexPath)
if let configurable = cell as? ConfigurableComponent, let object = self.object(at: indexPath) {
let item = self.dataSource[indexPath.row]
configurable.selected = item.selected
}
return cell
}
When call didSelectRowAt, just take item and change selected field, sample:
func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
let item = self.dataSource[indexPath.row]
item.selected = !item.selected
tableView.reloadData()
}