Table view with button that changes label based on user input - ios

Question

I'm trying to create a table view with just 1 label and 1 button in the prototype cell.
When you click the button, it asks the user for text input, and then replaces the label in the same cell with that text. I have been able to create a version of this where pressing the button updates the corresponding label with pre-determined text, but not input text.
The problems are:
(a) Can't seem to run an alert asking for user input in the TableViewCell class I created - must be in the ViewController to do that it seems?
(b) Have set up a TableCellDelegate protocol, and can detect a button press, then pass back to the ViewController to run the alert, but can't find a way to send the text input back to the TableViewCell to be updated.
Any help would be appreciated.
Here is the ViewController code:
import UIKit
class ViewController: UIViewController {
#IBOutlet weak var tableView: UITableView!
override func viewDidLoad() {
super.viewDidLoad()
tableView.delegate = self
tableView.dataSource = self
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
}
}
extension ViewController: TableCellDelegate {
func didTapButton(label: String) {
print(label)
}
}
extension ViewController: UITableViewDataSource, UITableViewDelegate {
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return 5
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "tableCell") as! TableViewCell
let label = "Label " + String(indexPath.row)
cell.setLabel(label: label)
cell.delegate = self
return cell
}
}
And here is the TableViewCell (without the alert coding):
import UIKit
protocol TableCellDelegate {
func didTapButton (label: String)
}
class TableViewCell: UITableViewCell {
#IBOutlet weak var tableCellLabel: UILabel!
var delegate: TableCellDelegate?
func setLabel(label: String) {
tableCellLabel.text = label
}
#IBAction func buttonTapped(_ sender: Any) {
delegate?.didTapButton(label: tableCellLabel.text!)
tableCellLabel.text = "pressed"
}
}
Finally, here is the alert code I am trying to insert in place of the tableCellLabel.text = "pressed" code above:
// Create the alert window
let buttonAlert = UIAlertController(title: "Label", message: "Enter Label", preferredStyle: UIAlertControllerStyle.alert)
// Add text input field to alert controller
buttonAlert.addTextField { (buttonLabel:UITextField!) -> Void in
buttonLabel.placeholder = "Enter Label"
}
// Create alert action for OK button
let okButtonAction = UIAlertAction.init(title: "OK", style: UIAlertActionStyle.default) { (alert:UIAlertAction!) -> Void in
// Get the button name from the alert text field
let buttonLabel = buttonAlert.textFields![0]
let buttonLabelString = buttonLabel.text
self.tableCellLabel.text = buttonLabelString
// Dismiss alert if ok pressed
buttonAlert.dismiss(animated: true, completion: nil)
}
// Add ok Button alert actions to alert controller
buttonAlert.addAction(okButtonAction)
// Create alert action for a cancel button
let cancelAction = UIAlertAction.init(title: "Cancel", style: UIAlertActionStyle.cancel) { (alert:UIAlertAction!) -> Void in
// Dismiss alert if cancel pressed
buttonAlert.dismiss(animated: true, completion: nil)
}
// Add Cancel Button alert actions to alert controller
buttonAlert.addAction(cancelAction)
// Display the alert window
self.present(buttonAlert, animated: true, completion: nil)
Where this goes wrong is the self.present(buttonAlert, animated: true, completion: nil), which it doesn't appear you can call from a table cell.

Answer 1

Depending on how you have the UItableview set up, it sounds like you're going to want to take the id of the data of the cell that is registering the alert and then updating the button text in that cell based on that within the table view render statement. Remember that setting the label of a button has an animation, it can cause some odd things to happen if you're animating other things at the same time.
You'll probably want to look at reload rows in the link below in your table view. Be careful though, the indexPath is not always the same as when the user interaction is called if you're using dequeueReusableCell.
UITableView Reference
See UIButton Reference for swift implementation, you'll have to set it for the current state of the button.