I have an app which utilizes a tableView which contains a prototype cell. This prototype cell contains a few labels and a button (connected to that cell's UITableViewCell file). If that's not clear, this is what I mean:
class ContactsCell: UITableViewCell { //this custom cell is used as the prototype cell for the tableView
#IBOutlet weak var firstNameLabel: UILabel!
#IBOutlet weak var lastNameLabel: UILabel!
#IBOutlet weak var numberLabel: UILabel!
#IBOutlet weak var indexPathRowLabel: UILabel!
#IBOutlet weak var replaceContactButtonUI: UIButton!
#IBAction func replaceContactButtonTapped(_ sender: Any) {
//THIS is the button in question
}
The reason for this is because I'd like each cell in the tableView to have all of those labels (and the button), but with each row having different values in the labels. These values are handled by the cellForRowAt tableView function, via a system as follows:
Pressing a button (not the button in the cells I was talking about... a different button that is at the top of the VC, outside of the tableView) brings up the contact picker:
func selectContact(){//allows user to bring up contactPicker
let contactPicker = CNContactPickerViewController()
contactPicker.displayedPropertyKeys = [CNContactGivenNameKey, CNContactFamilyNameKey, CNContactPhoneNumbersKey, CNContactImageDataKey]
contactPicker.delegate = self
contactPicker.predicateForEnablingContact = NSPredicate(format: "phoneNumbers.#count >= 0")
contactPicker.predicateForSelectionOfContact = NSPredicate(format: "phoneNumbers.#count >= 1")
self.present(contactPicker, animated: true, completion: nil)
}
#IBAction func selectContactsButton(_ sender: Any) {
selectContact()
//button brings up the picker to allow selection of contact
}
Selecting one of the contacts updates an array which is used by the tableView to update the value of the labels:
func contactPicker(_ picker: CNContactPickerViewController, didSelect contactProperty: CNContactProperty) {
contactArray.append(contactProperty.contact)
print(contactArray)// contactArray = [CNContact]()
contactsTableView.reloadData()// reloads the value of the labels
dismiss(animated: true)
}
These all work as intended. However, I run into a bit of an issue with the button that is in each cell. This button is intended to allow the replacement of a the CNContact in the tableView at the row of which the button was pressed... (ie if there are 4 rows, there are 4 "replace" buttons. Clicking the "replace" button of the third row replaces the CNContact at the 2nd index of the contactArray). This is where my issue is, though. Since the button, and its action, lives in the UITableViewCell's swift file, and not in the tableViewControllers, it doesn't have access to the contactArray to remove and append, nor the picker functions to allow the selection of the new contact, nor the tableView itself to run .reloadData(). How do I 'give access' to the UITableViewCell's swift file to utilize things from the tableView controller that it is a part of/connected to?
Note Its possible that the entire premise of this question is wrong and that I should've actually placed the button's action elsewhere (not in the UITableViewCell's swift file). If this is the case, where should I put it?
Since you have all the information in your ViewController, I would suggest moving your #IBAction into your ViewController as well. If you are worried about referencing the correct cell, you can set the tag value of your UIButton in cellForRow method. Then in #IBAction, you can use that value to access the correct index in the array as well as the cell itself
you can give selector to button in cellforrowatindexpath:
cell.replaceContactButtonUI.tag = index.row
cell.replaceContactButtonUI.addTarget(self, action: #selector(self.
selectContact(sender:)), for: .touchUpInside)
func selectContact(sender:UIButton){}
From button tag you can find the cell index by sender.tag.
Related
I have been searching through many posts on SO but couldn't find an answer to this one.
I have a Table view listing various items. Each cell in the table view has a button that swaps an image around when clicked on, effectively working as an "on" or "off" button to show a user which items in the list they have selected. I have a variable inside my custom Cell Prototype class which stores a value of true or false which is updated every time the button is clicked on.
There is a "Done" button in the Table View that when tapped on calls an unwind Segue to go back to the first View Controller.
When the user taps on the Enter Table View button (on the first View Controller) to display the Table the buttons all go back to their default state, am guessing because each time the segue to the Table View Screen happens it creates a new instance of the Table to be displayed.
What I'm trying to achieve is that the state of the button (either on or off) is retained when going back into the Table screen. I've tried for a while sending an Integer value back from the TableCell Class (using a delegate) to the first View controller and then passing that value back into the Table View controller when the forward segue is called in order to have a "retained from the previous state value" that can be compared against when the cells are created to indicate if a button had been clicked or not. Couldn't get it to work though to save the state of the buttons. The list of Items in the Table will also change depending on what a user adds.
Some Screen shots and the code are below. The code hasn't got the delegate i was trying included (as it didn't work) but if its needed I will edit the post to include it. Any help would be hugely appreciated. Many Thanks!!
Code I have so far is:
//Main View Controller//
class ViewController: UIViewController {
override func viewDidLoad() {
super.viewDidLoad()
}
//segue to the Table View Screen
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
if segue.identifier == "EnterTableView" {
let newTableView = segue.destination as! TableViewController
}
}
// Unwind Segue Called on Exit From Table View
#IBAction func unwindToMainViewController (_segue:UIStoryboardSegue) {
}
}
// Table View Controller //
class TableViewController: UITableViewController {
var dataArray = ["A", "B", "C", "D"]
override func viewDidLoad() {
super.viewDidLoad()
}
// MARK: - Table view data source
override func numberOfSections(in tableView: UITableView) -> Int {
//create one section for table
return 1
}
override func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
//create number of rows based on the number of items in the dataArray set above
return dataArray.count
}
// an array that will contain all the cells
var cellArray = [UITableViewCell] ()
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
//create a new cell based on the cell class "TableViewCell"
let cell = tableView.dequeueReusableCell(withIdentifier: "TableViewCell", for: indexPath) as? TableViewCell
// variable to contain a single element from the dataArray - updates every time a new cell is created
let dataArrayForCells = dataArray [indexPath.row]
//set cell label text to show the value from the dataArrayForCells
cell!.label.text = dataArrayForCells
cellArray.append(cell!)
return cell!
}
// Table Cell Class//
class TableViewCell: UITableViewCell {
#IBOutlet weak var label: UILabel! // label to hold display some text
#IBOutlet weak var buttonImage: UIImageView! //image for button
var buttonClicked = true //variable to contain weather the has been clicked
//if button is tapped on run the below
#IBAction func aButton(_ sender: Any) {
//if button is clicked is true, swap image to red ("on") button, set buttonClicked value to false
if buttonClicked {
buttonImage.image = #imageLiteral(resourceName: "Rec Button Red")
buttonClicked = false
}
// if buttonClicked value is false swap image to grey ("off") button set buttonClicked value back to true
else {
buttonImage.image = #imageLiteral(resourceName: "Rec Button Grey")
buttonClicked = true
}
}
I have a tableView with a custom cell that has a UITextView inside it and I want to make the UITextView of the last cell in the tableView the firstresponder when a button is pressed. However, I'm not sure how to reference that UITextView inside the cell.
It has an outlet in the custom cell class, but I don't know how to use this button (an action in another class) to reference it.
class ActionCell: UITableViewCell {
#IBOutlet weak var label: UITextView!
}
What I tried is this, but it doesn't work:
#IBAction func addAction(_ sender: Any) {
let cell = tableview.cellForRow(at: IndexPath.init(row: -1, section: 1)) as? ActionCell
let textview = cell?.contentView.subviews.filter{$0 is UITextView}
textview![0].becomeFirstResponder()
}
I have a custom UIView with 3 tableviews, the tableviews are self-sizing depending on the content they have, and they a show a different nib when they are empty than when they have content. All of this is embedded in a scroll view and it's working already, my view scrolls and the tableviews display the content appropriately and they autosize properly, the scroll view's size is adjusting without problems either.
In two of the tableviews when the tableviews have items there are some buttons in the cell nib that I want to access along with the index of the cell clicked inside the View controller where I have defined the Table view.
Here in the pic I'm showing the tableViews each with one item, the Canastas tableView has just a delete item button and the Productos tableView has a delete item button and a stepper to increase or decrease the amount.
I found a solution involving delegates in StackOverflow
Get button click inside UI table view cell, which I implemented. But for some reason it isn't working and the code in the delegate method isn't being executed.
Here is my code:
CanastasViewCell
import UIKit
protocol CanastasViewCellDelegate: class {
func closeButtonTapped(at index: IndexPath)
}
class CanastasViewCell: UITableViewCell {
#IBOutlet weak var imagenProducto: UIImageView!
#IBOutlet weak var nombreProducto: UILabel!
#IBOutlet weak var descProducto: UILabel!
#IBOutlet weak var precioProducto: UILabel!
#IBOutlet weak var closeButton: UIButton!
weak var delegate: CanastasViewCellDelegate?
var indexPath: IndexPath!
override func awakeFromNib() {
super.awakeFromNib()
}
#IBAction func eliminarProducto(_ sender: AnyObject) {
self.delegate?.closeButtonTapped(at: indexPath)
}
}
CarritoViewController
import UIKit
class CarritoViewController: UIViewController, UITableViewDelegate,
UITableViewDataSource, CanastasViewCellDelegate {
func closeButtonTapped(at index: IndexPath) {
print("Button tapped at index:\(index)")
}
It looks like you're not setting the delegate inside CarritoViewController. You'll want to make sure that you set cell.delegate = self inside func tableView(UITableView, cellForRowAt: IndexPath).
I currently have a ViewController with a TableView inside it called SelectedListItemsViewController. This ViewController's TableView is populated by a custom cell class called SelectedListItemsTableViewCell.
I have an array of Realm Model Objects called selectedListItems, each of which has several properties. The SelectedListItemsTableViewCell populates the TableView with the listItem property of that indexPath.row's object, and each row has a UIStepper with a UILabel next to it that (as of now) shows UIStepper.value for each row. Ideally, the label will reflect the listItemWeight property of each row, and change it when incrementing or decrementing that row.
This is my custom cell:
class SelectedListItemsTableViewCell: UITableViewCell {
#IBOutlet var selectedListItemLabel: UILabel!
#IBOutlet weak var listItemWeightLabel: UILabel!
#IBOutlet weak var stepperControl: UIStepper!
#IBAction func stepperValueChanged(sender: UIStepper) {
listItemWeightLabel.text = Int(sender.value).description
}
}
And in my ViewController's cellForRowAtIndexPath, I've configured the cell like so:
// Configure the cell...
cell.selectedListItemLabel.text = selectedListItems[indexPath.row].listItem
cell.listItemWeightLabel.text = "\(selectedListItems[indexPath.row].listItemWeight)"
Which perfectly loads the listItem property, and the listItemWeight property shows up correctly, but as soon as I increment or decrement on the UIStepper it gets messed up.
How do I properly link my UILabel and UIStepper to the [indexPath.row].listItemWeight?
In the same method that gets called when your stepper updates, update your listItem. However, since this item is stored in your Realm database, you will have to get an instance of your Realm database and write the change to the database.
You can do this by having your TableViewCell hold on to an instance of the listItem. Your new TableViewCell class will look something like this:
class SelectedListItemsTableViewCell: UITableViewCell {
#IBOutlet var selectedListItemLabel: UILabel!
#IBOutlet weak var listItemWeightLabel: UILabel!
#IBOutlet weak var stepperControl: UIStepper!
var listItem: Item?
#IBAction func stepperValueChanged(sender: UIStepper) {
listItemWeightLabel.text = Int(sender.value).description
if let listItem = listItem {
let realm = try! Realm
try! realm.write {
listItem.listItemWeight = Int(sender.value) ?? 0
}
}
}
}
The above answer was helpful in leading me to the actual solution of my issue, but if anyone in the future is curious - I ended up using a closure.
In my custom cell class, I did
#IBAction func stepperValueChanged(sender: UIStepper) {
selectedListItemLabel.text = Int(sender.value).description
tapped?(self)
}
And in my view controller, I did
func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCellWithIdentifier("Cell", forIndexPath: indexPath) as! SelectedListItemsTableViewCell
cell.stepperControl.value = selectedListItems[indexPath.row].listItemWeight
// Configure the cell...
cell.tapped = { (selectedCell) -> Void in
selectedListItems[indexPath.row].listItemWeight = cell.stepperControl.value
}
Which allowed me to access each cell's UIStepper in the view controller file.
It helped to read flashadvanced's Option 2 answer in this thread.
When a button is clicked (thats located inside the cell of a tableview), I pass a reference to it to another class. However, along with it I also want to pass a reference to another button in the same cell. I can easily reference the clicked button as "sender", but how would I reference the other button in the same cell?
This is in the cell subclass, not the main view controller.
class ImageTableViewCell: UITableViewCell {
#IBOutlet weak var upVote: UIButton!
#IBOutlet weak var downVote: UIButton!
#IBAction func upVote(sender: AnyObject) {
self.delegate?.controller(self, button: sender as! UIButton, other: *REFERENCE DOWNVOTE BUTTON HERE*, selectedButtonIndexPath: indexPath!)
}
}
The cell has a property for each button.
Since it appears that you have separate action methods for each button, the other button is known to you and you can pass it directly:
#IBAction func upVote(sender: AnyObject) {
self.delegate?.controller(self, button: sender as! UIButton, other: downVote, selectedButtonIndexPath: indexPath!)
}
If you don't know which button is which, you can determine the opposite button by
let other = sender === self.upVote ? self.downVote : self.upVote