I am new in Swift and I am not able to access IBOutlet variable in tableview cell inside tableview cell.
My code is something like this.
In view controller:
#IBOutlet var lblPopupTitle: UILabel!
In Tableview Inside Cell:
cell.btnEdit.tag = indexPath.item
cell.btnEdit.addTarget(self, action: #selector(btnEdit), for: .touchUpInside)
In Tableview Cell:
class AttendanceInOutCell: UITableViewCell {
#IBOutlet var txtStartAt: UITextField!
override func awakeFromNib() {
super.awakeFromNib()
}
#objc func btnEditClick(_ sender: UIButton)
{
let index = IndexPath(row: sender.tag, section: 0)
let cell: AttendanceInsideCell = tableAway.cellForRow(at: index) as! AttendanceInsideCell
lblPopupTitle.text = cell.txtAwayStart.text
}
}
lblPopupTitle show me "Use of unresolved identifier 'lblPopupTitle'". How can I solve this issue?
There are several ways to achieve this.
Protocol- Delegate approach:
protocol PassDataDelagate: class {
func passtextFieldText(_ startText: String)
}
Make a protocol in class:
AttendanceInOutCell: UITableViewCell {
#IBOutlet var txtStartAt: UITextField!
weak var textDelegate: PassDataDelagate?
override func awakeFromNib() {
super.awakeFromNib()
}
#objc func btnEditClick(_ sender: UIButton)
{
let index = IndexPath(row: sender.tag, section: 0)
let cell: AttendanceInsideCell = tableAway.cellForRow(at: index) as! AttendanceInsideCell
textDelegate?.passtextFieldText(cell.txtAwayStart.text)
}
}
Inside Tableview Cell, add this line:
cell.btnEdit.tag = indexPath.item
cell.textDelegate = self
cell.btnEdit.addTarget(self, action: #selector(btnEdit), for: .touchUpInside)
Add this in view controller:
func passtextFieldText(_ startText: String) {
lblPopupTitle.text = startText
}
P.S: You can also pass multiple information in the delegate function if you want.
protocol AttendanceDelegate: class {
func didTapOnBtn(_ popUpTitle: String)
}
class AttendanceInOutCell: UITableViewCell {
#IBOutlet var txtStartAt: UITextField!
weak var delegate: AttendanceDelegate?
override func awakeFromNib() {
super.awakeFromNib()
}
#objc func btnEditClick(_ sender: UIButton)
{
let index = IndexPath(row: sender.tag, section: 0)
let cell: AttendanceInsideCell = tableAway.cellForRow(at: index) as! AttendanceInsideCell //( I'm not getting this from where you get this tableAway variable) // So I m just telling you how you can set lblpopupTitle.text in viewController
lblPopupTitle.text = cell.txtAwayStart.text // remove this line
self.delegate.didTapOnBtn(cell.txtAwayStart.text) // please unwrap the textfield text before passing it as parameter
}
}
// for view controller
// there must be as tableview cellforRowAt function where you are creating your cell
// so after creating the cell instance
// add this line ( cell.delegate = self) and return cell
// now add extension to your controller
extension ViewController: AttendanceDelegate {
func didTapOnBtn(_ popUpTitle: String) {
lblPopupTitle.text = popUpTitle
}
}
Related
I am trying to instantiate empty Buyer cells (custom cell) in my table view and then have the user populate the buyers' names. When the user presses the delete button for a row/cell, it should delete the corresponding row/cell regardless of whether or not the textfield for that row has been populated or not. Clearly, I am not getting the desired behavior. For example, when I press delete Row0 (whose textfield says "Buyer 0") and the tableview reloads, Buyer 0 is still there, but one of the empty Buyer cells at the end gets deleted instead.
import UIKit
class EntryAlertViewController: UIViewController {
//Fields/Table
#IBOutlet weak var itemField: UITextField!
#IBOutlet weak var priceField: UITextField!
#IBOutlet weak var tableView: UITableView!
//Visual Components
#IBOutlet weak var mainView: UIView!
#IBOutlet weak var titleView: UIView!
#IBOutlet weak var splitItemButton: UIButton!
#IBOutlet weak var cancelButton: UIButton!
#IBOutlet weak var addItemButton: UIButton!
//Commonly Used Objects/Variables
var potentialBuyers: [String] = []
override func viewDidLoad() {
super.viewDidLoad()
potentialBuyers.append("")
tableView.dataSource = self
tableView.register(UINib(nibName: "BuyerCell", bundle: nil), forCellReuseIdentifier: "ReusableCell")
}
override func viewWillAppear(_ animated: Bool) {
}
#IBAction func splitItemPressed(_ sender: UIButton) {
potentialBuyers.append("")
tableView.reloadData()
}
}
Here are the tableview datasource and the delete button delegate.
extension EntryAlertViewController: UITableViewDataSource, DeleteButtonDelegate {
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return potentialBuyers.count
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "ReusableCell", for: indexPath) as! BuyerCell
cell.deleteButtonDelegate = self
cell.indexPath = indexPath
cell.nameField.text = cell.buyerName
if potentialBuyers.count == 1 {
cell.deleteButton.isHidden = true
} else {
cell.deleteButton.isHidden = false
}
return cell
}
func deletePressed(index: Int) {
potentialBuyers.remove(at: index)
tableView.reloadData()
}
}
And here is my BuyerCell class with the UITextFieldDelegate as an extension.
import UIKit
protocol DeleteButtonDelegate {
func deletePressed(index: Int)
}
class BuyerCell: UITableViewCell {
#IBOutlet weak var deleteButton: UIButton!
#IBOutlet weak var nameField: UITextField!
var deleteButtonDelegate: DeleteButtonDelegate!
var indexPath: IndexPath!
var buyerName: String?
override func awakeFromNib() {
super.awakeFromNib()
self.nameField.delegate = self
}
#IBAction func deletePressed(_ sender: UIButton) {
//print the indexPath.row that this was pressed for
print("delet pressed for \(indexPath.row)")
self.deleteButtonDelegate?.deletePressed(index: indexPath.row)
}
override func setSelected(_ selected: Bool, animated: Bool) {
super.setSelected(selected, animated: animated)
// Configure the view for the selected state
}
}
extension BuyerCell: UITextFieldDelegate {
func textFieldDidBeginEditing(_ textField: UITextField) {
print("textFieldDidBeginEditing")
buyerName = nameField.text
}
func textFieldDidEndEditing(_ textField: UITextField) {
print("textFieldDidEndEditing")
buyerName = nameField.text
}
}
Your problem is in this line
cell.nameField.text = cell.buyerName
Cells are reused from a reuse pool, so you can't rely on the cell holding any particular state or value.
Your buyer name needs to come from your data model array.
Something like
cell.nameField.text = self.potentialBuyers[indexPath.row]
Reloading the whole tableview is a bit excessive when you have only deleted a single row; Just delete the relevant row.
You can also clean up your delegation protocol so that there is no need for the cell to track its indexPath -
protocol DeleteButtonDelegate {
func deletePressed(in cell: UITableViewCell)
}
In your cell:
#IBAction func deletePressed(_ sender: UIButton) {
self.deleteButtonDelegate?.deletePressed(in: self)
}
In your view controller:
func deletePressed(in cell: UITableViewCell) {
guard let indexPath = tableView.indexPath(for: cell) else {
return
}
potentialBuyers.remove(at: indexPath.row)
tableView.deleteRows(at:[indexPath], with: .automatic)
}
There is a major issue in your code. You are not updating the data model so the changes in the cells are lost when the user scrolls.
Rather then quite objective-c-ish protocol/delegate in Swift callback closures are much more convenient and efficient. You can use one callback for both updating the model and deleting the cell.
Replace the BuyerCell cell with
class BuyerCell: UITableViewCell {
#IBOutlet weak var deleteButton: UIButton!
#IBOutlet weak var nameField: UITextField!
var callback : ((UITableViewCell, String?) -> Void)?
override func awakeFromNib() {
super.awakeFromNib()
self.nameField.delegate = self
}
#IBAction func deletePressed(_ sender: UIButton) {
callback?(self, nil)
}
}
extension BuyerCell: UITextFieldDelegate {
func textFieldDidBeginEditing(_ textField: UITextField) {
print("textFieldDidBeginEditing")
callback?(self, nameField.text)
}
func textFieldDidEndEditing(_ textField: UITextField) {
print("textFieldDidEndEditing")
callback?(self, nameField.text)
}
}
In the controller in cellForRow assign the callback and handle the actions. The actions work also reliably if cells are reordered, inserted or deleted.
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "ReusableCell", for: indexPath) as! BuyerCell
let buyerName = potentialBuyers[indexPath.row]
cell.nameField.text = buyerName
cell.callback = { [unowned self] cCell, cName in
let currentIndexPath = tableView.indexPath(for: cCell)!
if let name = cName {
self.potentialBuyers[currentIndexPath.row] = name
} else {
self.potentialBuyers.remove(at: currentIndexPath.row)
tableView.deleteRows(at: [currentIndexPath], with: .fade)
}
}
cell.deleteButton.isHidden = potentialBuyers.count == 1
return cell
}
I'm trying to call a function() made in my first ViewController from another function() made in the second ViewController.
It's a function to update the title of a button in the firstViewController.
I have searched but I can't find a way.
First ViewController // ViewController.swift
import UIKit
class ViewController: UIViewController, UITextFieldDelegate {
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view, typically from a nib.
weightLabel.delegate = self
}
#IBAction func excerciseChooserButton(_ sender: UIButton) {
}
var weight = 0 {
didSet {
weightLabel.text = "\(weight)"
}
}
// User input WEIGHT
#IBOutlet weak var weightLabel: UITextField!
func textField(_ weightLabel: UITextField, shouldChangeCharactersIn range: NSRange, replacementString string: String) -> Bool {
let isNumber = CharacterSet.decimalDigits.isSuperset(of: CharacterSet(charactersIn: string))
let withDecimal = (
string == NumberFormatter().decimalSeparator &&
weightLabel.text?.contains(string) == false
)
return isNumber || withDecimal
}
#IBAction func plusWeight(_ sender: UIButton) {
weight += 5
}
#IBAction func minusWeight(_ sender: UIButton) {
weight -= 5
}
// User input REPS
#IBOutlet weak var repLabel: UILabel!
#IBAction func repSlider(_ sender: UISlider) {
let currentRepValue = Int(sender.value)
repLabel.text = "\(currentRepValue)"
let cm = Calculator(weight: weightLabel.text!, reps: repLabel.text!)
let result = cm.calcRM()
repMax.text = "1RM: \(result)kg"
}
#IBOutlet weak var repMax: UILabel!
#IBOutlet weak var excerciseLabel: UIButton!
func changeText() {
excerciseLabel.setTitle(Excercises.excChosen, for: .normal)
print(excerciseLabel)
}
#IBAction func unwindToViewController(segue:UIStoryboardSegue) {
}
}
// // // //
Second ViewController // ExcerciseChooserViewController.swift
import UIKit
struct Excercises {
static var excChosen:String? = ""
}
class ExcerciseChooserViewController: UIViewController, UITableViewDelegate, UITableViewDataSource
// Data model: These strings will be the data for the table view cells
let excercises: [String] = ["Bench Press", "Squat", "Push Press", "Deadlift"]
// cell reuse id (cells that scroll out of view can be reused)
let cellReuseIdentifier = "cell"
// don't forget to hook this up from the storyboard
#IBOutlet var tableView: UITableView!
override func viewDidLoad() {
super.viewDidLoad()
// Register the table view cell class and its reuse id
self.tableView.register(UITableViewCell.self, forCellReuseIdentifier: cellReuseIdentifier)
// (optional) include this line if you want to remove the extra empty cell divider lines
// self.tableView.tableFooterView = UIView()
// This view controller itself will provide the delegate methods and row data for the table view.
tableView.delegate = self
tableView.dataSource = self
}
// number of rows in table view
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return self.excercises.count
}
// create a cell for each table view row
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
// create a new cell if needed or reuse an old one
let cell:UITableViewCell = self.tableView.dequeueReusableCell(withIdentifier: cellReuseIdentifier) as UITableViewCell!
// set the text from the data model
cell.textLabel?.text = self.excercises[indexPath.row]
return cell
}
// method to run when table view cell is tapped
func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
let excerciseChosen = "\(excercises[indexPath.row])"
print("You tapped cell number \(indexPath.row).")
print(excerciseChosen)
goBackToOneButtonTapped((Any).self)
Excercises.excChosen = excerciseChosen
print(Excercises.excChosen!)
// call function to update text
ViewController.changeText()
}
#IBAction func goBackToOneButtonTapped(_ sender: Any) {
performSegue(withIdentifier: "unwindToViewController", sender: self)
}
}
Call it from unwindToViewController instead, no need to call it while the first view controller is not visible
There are many ways to do this, but I'll describe a simple one here.
Because you're going back to 'ViewController' via a segue, a good option for you is to override prepare(for:sender:). This will give you a reference to the destination view controller of that segue, which will then allow you to call functions or set properties in that view controller. You can read more about this method here.
Here are some basic steps:
In ViewController, update your changeText() method to accept a string parameter: changeText(_ text: String?).
Add a property to ExcerciseChooserViewController to hold the text you want to use: private var chosenExercise: String?
In your tableView:DidSelectRowAtIndexPath: method, set your new chosenExercise property to the string you want to pass to ViewController.
In prepare(for:sender:) of ExcerciseChooserViewController, grab a reference to destination view controller, downcast it to your subclass ViewController, and call your new method passing in the exerciseText string.
For example:
class ViewController: UIViewController, UITextFieldDelegate {
#IBOutlet weak var excerciseLabel: UIButton!
func changeText(_ text: String?) {
guard let text = text else { return }
excerciseLabel.setTitle(text, for: .normal)
print(excerciseLabel)
}
}
And in ExcerciseChooserViewController:
class ExcerciseChooserViewController: UIViewController, UITableViewDelegate, UITableViewDataSource {
private var chosenExercise: String?
// method to run when table view cell is tapped
func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
let excerciseChosen = "\(excercises[indexPath.row])"
print("You tapped cell number \(indexPath.row).")
print(excerciseChosen)
goBackToOneButtonTapped((Any).self)
Excercises.excChosen = excerciseChosen
print(Excercises.excChosen!)
chosenExercise = excerciseChosen
}
#IBAction func goBackToOneButtonTapped(_ sender: Any) {
performSegue(withIdentifier: "unwindToViewController", sender: self)
}
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
if let destinationVC = segue.destination as? ViewController {
destinationVC.changeText(chosenExercise)
}
}
}
I have a TableViewCell class like this:
class CampaignsTableViewCell: UITableViewCell {
#IBOutlet weak var activateButton: UIButton!
#IBOutlet weak var titleCampaignPlaceholder: UILabel!
override func awakeFromNib() {
super.awakeFromNib()
// Initialization code
setUpButton()
}
override func setSelected(_ selected: Bool, animated: Bool) {
super.setSelected(selected, animated: animated)
// Configure the view for the selected state
}
private func setUpButton(){
activateButton.backgroundColor = .clear
activateButton.layer.cornerRadius = 5
activateButton.layer.borderWidth = 1
activateButton.layer.borderColor = UIColor.blue.cgColor
}
}
And, in another class which is a ViewController I have my UITableView methods:
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let rowNumber = indexPath.row
let cellIdentifier = "CampaignTableViewCell"
guard let cell = tableView.dequeueReusableCell(withIdentifier: cellIdentifier, for: indexPath) as? CampaignsTableViewCell else {
fatalError("The dequeued cell is not an instance of TableViewCellController.")
}
cell.titleCampaignPlaceholder.text = campaignsArray[rowNumber].campaignName
return cell
}
I need to use my activateButton in my UITableView method in order to access to campaignsArray. I have another method which requieres values from that array, so I need that method is called every time activateButton is pressed from my UITableView.
Any idea ?
Thank you very much
What I like doing in those cases where you have a button inside your UITableViewCell is the following:
Give the cell a closure that is called when tapping on the button like so
class CampaignsTableViewCell: UITableViewCell {
... all your code....
// give your cell a closure that is called when the button is pressed
var onButtonPressed: ((_ sender: UIButton) -> ())?
#IBAction func buttonPressed(sender: UIButton) { // wire that one up in IB
onButtonPressed?(sender)
}
}
and then inside your TableViewController
let cell = tableView.dequeueReusableCell(withIdentifier: cellIdentifier, for: indexPath) as! CampaignsTableViewCell
cell.titleCampaignPlaceholder.text = campaignsArray[rowNumber].campaignName
cell.onButtonPressed = { [weak self] sender in
// Do your magic stuff here
}
return cell
Hope that helps
Your cell will get that event, not tableView. What you need to do is:
Create protocol inside your cell:
protocol CampaignsTableViewProtocol{
func actionButtonPressed(row: Int)
}
class CampaignsTableViewCell: UITableViewCell {
#IBOutlet weak var activateButton: UIButton!
#IBOutlet weak var titleCampaignPlaceholder: UILabel!
// keep info about row
var rowIndex: Int = -1
// create delegate that will let your tableView about action button in particular row
var delegate : CampaignsTableViewProtocol?
override func awakeFromNib() {
super.awakeFromNib()
// Initialization code
setUpButton()
self. activateButton.addTarget(self, action: #selector(self.activatePressed), for: UIControlEvents.touchDown)
}
override func setSelected(_ selected: Bool, animated: Bool) {
super.setSelected(selected, animated: animated)
// Configure the view for the selected state
}
func activatePressed(){
self.delegate?.actionButtonPressed(row :rowIndex)
}
private func setUpButton(){
activateButton.backgroundColor = .clear
activateButton.layer.cornerRadius = 5
activateButton.layer.borderWidth = 1
activateButton.layer.borderColor = UIColor.blue.cgColor
}
}
Your tableViewController needs to adopt this protocol:
class MyTableViewController: UITableViewDelegate, UITableViewDataSource, CampaignsTableViewProtocol {
// rest of the code
}
Also, you will need to implement delegate function in your tableViewController:
func actionButtonPressed(row: Int) {
// get campaign you need
let campaign = campaignsArray[row]
// rest of the code
}
I have a table view where I have created a label and two buttons. I am stuck while getting the text from the label on button click. I have created an array list like:
let arrayList: [String] = [ "aaa" , "bbb" , "ccc"]
I want if I click the button on index[0] I shall get "aaa" and if index[2] I shall get "ccc"
#IBOutlet weak var titleLable: UILabel!
#IBOutlet weak var infoButton: UIButton!
myCell.titleLable.text = self.arrayList[indexPath.row]
myCell.infoButton.tag = indexPath.row
myCell.infoButton.addTarget(self, action: "buttonClicked", forControlEvents: .TouchUpInside)
Try to get indexPath, where the button is clicked using the Button Tag.
#IBAction func buttonClicked(sender:UIButton) {
let cell = tableView.cellForRowAtIndexPath(NSIndexPath.init(forRow: sender.tag, inSection: 0))
cell.myLabel.text = arrayList[sender.tag]
}
you need to do like
swift3
myCell.titleLable.text = self.arrayList[indexPath.row]
myCell.infoButton.tag = indexPath.row
myCell.infoButton.addTarget(self, action: #selector(yourVCName.buttonClicked(_:)), for: .touchUpInside)
get action as
#IBAction func buttonClicked(_ sender: UIButton){
print(self.arrayList[sender. tag])
}
Swift2
myCell.titleLable.text = self.arrayList[indexPath.row]
myCell.infoButton.tag = indexPath.row
myCell.infoButton.addTarget(self, action: "buttonClicked:", forControlEvents: .TouchUpInside)
#IBAction func buttonClicked(sender: UIButton){
print(self.arrayList[sender. tag])
}
In your Table View Controller
let dataSource: [String] = [ "aaa" , "bbb" , "ccc"]
override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCellWithIdentifier(YourCellIdentifier, forIndexPath: indexPath) as! YourCell
let title = dataSource[indexPath.row]
cell.setup(withTitle: title, delegate: self)
return cell
}
// MARK: - Your Cell Delegate
func didTapActionButton(fromCell cell: UITableViewCell) {
if let indexPath = itemTable.indexPathForCell(cell) {
let selectedItem = dataSource[indexPath.row]
print(selectedItem)
}
}
In your Table View Cell
Firstly, define a protocol:
protocol YourTableViewCellDelegate {
func didTapActionButton(fromCell cell: UITableViewCell)
}
And then:
// MARK: - Properties
var delegate: YourTableViewCellDelegate?
// MARK: - #IBOutlets
#IBOutlet weak var titleLabel: UILabel!
#IBOutlet weak var infoButton: UIButton!
// MARK: - #IBActions
#IBAction func buttonClicked(sender: UIButton) {
delegate?.didTapActionButton(fromCell: self)
}
// MARK: - Public Methods
func setup(withTitle title: title, delegate: YourTableViewCellDelegate?) {
titleLabel.text = title
self.delegate = delegate
}
I have a CollectionViewController with 3 buttons populated. The view works well, but how do I select different view controllers based on the button selected? I added the button as an action, but I don't know how to specify which button is selected so I can send the user to different viewcontrollers.
import UIKit
private let reuseIdentifier = "Cell"
class CollectionViewController: UICollectionViewController {
var imageArray = [UIImage(named: "tempOwl.png"), UIImage(named: "tempPuzzle.png"), UIImage(named: "tempHouse.png")]
override func viewDidLoad() {
super.viewDidLoad()
self.clearsSelectionOnViewWillAppear = false
self.collectionView!.registerClass(UICollectionViewCell.self, forCellWithReuseIdentifier: reuseIdentifier)
}
#IBAction func menuButton(sender: UIButton) {
let controller = storyboard?.instantiateViewControllerWithIdentifier("myHome")
presentViewController(controller!, animated: true, completion: nil)
}
override func numberOfSectionsInCollectionView(collectionView: UICollectionView) -> Int {
return 1
}
override func collectionView(collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
return 3
}
override func collectionView(collectionView: UICollectionView, cellForItemAtIndexPath indexPath: NSIndexPath) -> UICollectionViewCell {
let cell = collectionView.dequeueReusableCellWithReuseIdentifier("cell", forIndexPath: indexPath) as UICollectionViewCell
let imageView = cell.viewWithTag(1) as! UIButton
imageView.setBackgroundImage(self.imageArray[indexPath.row], forState: .Normal)
return cell
}
}
The button action method for your button in cell
func buttonAction(sender : UIButton) {
var selectedButtonCell = sender.superview as! UICollectionViewCell
//Incase your button is inside cell.contentview
// var selectedButtonCell = sender.superview.superview as! UICollectionviewCell
var indexPath = collectionView.indexPathForCell(selectedButtonCell)
if indexPath.row == 0 {
//Button in first cell is selected
//Send user to first button view controller
}
}
I suggest to create a class of type UICollectionViewCell and create the IBAction in the cell.
And set the collectionViewController as delegate. So you can pass values.
So you can create a function in the collection view controller and give it a param like a int 1 for cell 1.
If you have multiple buttons in the cell you should implement a delegate. Then, set your view controller as a delegate of the cell. Sample implementation of such a delegate could look like:
protocol YourCustomCellDelegate {
func firstButtonPressed(cell: YourCustomCell)
func secondButtonPressed(cell: YourCustomCell)
}
class YourCustomCell : UICollectionViewCell {
var delegate:YourCustomCellDelegate?
#IBOutlet weak var firstButton: UIButton!
#IBOutlet weak var secondButton: UIButton!
#IBAction func firstButtonTapped(sender: AnyObject) {
delegate?.firstButtonPressed(self)
}
#IBAction func secondButtonTapped(sender: AnyObject) {
delegate?.secondButtonPressed(self)
}
}