Swift passing parameter on #selector - ios

Question

How can I use the same function to handle DatePickerView on 2 different textFields?
To avoid repetition, I would like to set up 2 textFields with a DatePicker. One field is for issue date and the other one for due date.
When I try to add parameter on #objc func doneClick, I got a compiler error ==> Instance member 'doneClick' cannot be used on type 'InvoiceViewController'; did you mean to use a value of this type instead?
import UIKit
class InvoiceViewController: UIViewController, UITextFieldDelegate{
var thePicker = UIDatePicker()
#IBOutlet weak var dateIssueTextField: UITextField!
#IBOutlet weak var dueDateTextField: UITextField!
#objc func doneClick(textField: UITextField!) {
let dateFormatter = DateFormatter()
dateFormatter.dateStyle = .short
dateFormatter.timeStyle = .none
dateIssueTextField.text = dateFormatter.string(from: thePicker.date)
dateFormatter.dateFormat = "yyyy"
let year: String = dateFormatter.string(from: self.thePicker.date)
dateFormatter.dateFormat = "MM"
let month: String = dateFormatter.string(from: self.thePicker.date)
dateFormatter.dateFormat = "dd"
let day: String = dateFormatter.string(from: self.thePicker.date)
let finalDate = year+"-"+month+"-"+day
print(finalDate)
// dateIssueTextField.resignFirstResponder()
textField.resignFirstResponder()
}
#objc func cancelClick() {
dateIssueTextField.resignFirstResponder()
}
func setUpTextFieldPicker(textField: UITextField) {
// DatePicker
self.thePicker = UIDatePicker(frame:CGRect(x: 0, y: 0, width: self.view.frame.size.width, height: 216))
self.thePicker.backgroundColor = UIColor.white
self.thePicker.datePickerMode = UIDatePickerMode.date
// dateIssueTextField.inputView = thePicker
// dueDateTextField.inputView = thePicker
textField.inputView = thePicker
// ToolBar
let toolBar = UIToolbar()
toolBar.barStyle = .default
toolBar.isTranslucent = true
toolBar.tintColor = UIColor(red: 92/255, green: 216/255, blue: 255/255, alpha: 1)
toolBar.sizeToFit()
// Adding Button ToolBar
let doneButton = UIBarButtonItem(title: "Done", style: .plain, target: self, action: #selector(InvoiceViewController.doneClick))
let spaceButton = UIBarButtonItem(barButtonSystemItem: .flexibleSpace, target: nil, action: nil)
let cancelButton = UIBarButtonItem(title: "Cancel", style: .plain, target: self, action: #selector(InvoiceViewController.cancelClick))
toolBar.setItems([cancelButton, spaceButton, doneButton], animated: false)
toolBar.isUserInteractionEnabled = true
//dateIssueTextField.inputAccessoryView = toolBar
//dueDateTextField.inputAccessoryView = toolBar
textField.inputAccessoryView = toolBar
}
override func viewDidLoad() {
super.viewDidLoad()
setUpTextFieldPicker(textField: dateIssueTextField)
setUpTextFieldPicker(textField: dueDateTextField)
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
}
}

Answer 1

doneClick cannot have parameter of UITextField type, when it's used as a target to UIBarButtonItem.
You will have to edit more than just that method. The toolbar needs to know to which UITextField it belongs to. So create your custom subclass of UIToolbar, in which you will setup its items, and add a delegate to it which will be sent events on done and cancel pressed:
import UIKit
protocol AccessoryToolbarDelegate: class {
func doneClicked(for textField: UITextField)
func cancelClicked(for textField: UITextField)
}
class AccessoryToolbar: UIToolbar {
fileprivate let textField: UITextField
weak var accessoryDelegate: AccessoryToolbarDelegate?
init(for textField: UITextField) {
self.textField = textField
super.init(frame: CGRect.zero)
self.barStyle = .default
self.isTranslucent = true
self.tintColor = UIColor(red: 92/255, green: 216/255, blue: 255/255, alpha: 1)
self.sizeToFit()
let doneButton = UIBarButtonItem(title: "Done", style: .plain, target: self, action: #selector(doneClicked))
let spaceButton = UIBarButtonItem(barButtonSystemItem: .flexibleSpace, target: nil, action: nil)
let cancelButton = UIBarButtonItem(title: "Cancel", style: .plain, target: self, action: #selector(cancelClicked))
self.setItems([cancelButton, spaceButton, doneButton], animated: false)
self.isUserInteractionEnabled = true
textField.inputAccessoryView = self
}
required init?(coder aDecoder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
#objc fileprivate func doneClicked() {
accessoryDelegate?.doneClicked(for: self.textField)
}
#objc fileprivate func cancelClicked() {
accessoryDelegate?.cancelClicked(for: self.textField)
}
}
Now with this code you can rewrite your old code to:
import UIKit
class InvoiceViewController: UIViewController, AccessoryToolbarDelegate {
var thePicker = UIDatePicker()
#IBOutlet weak var dateIssueTextField: UITextField!
#IBOutlet weak var dueDateTextField: UITextField!
func doneClicked(for textField: UITextField) {
let dateFormatter = DateFormatter()
dateFormatter.dateStyle = .short
dateFormatter.timeStyle = .none
// I am not sure if you want this
textField.text = dateFormatter.string(from: thePicker.date)
// or rather this, but that's up to you to finish
dateFormatter.dateFormat = "yyyy-MM-dd"
let finalDate: String = dateFormatter.string(from: thePicker.date)
print(finalDate)
textField.resignFirstResponder()
}
func cancelClicked(for textField: UITextField) {
textField.resignFirstResponder()
}
func setUpTextFieldPicker(textField: UITextField) {
// DatePicker
self.thePicker = UIDatePicker(frame:CGRect(x: 0, y: 0, width: self.view.frame.size.width, height: 216))
self.thePicker.backgroundColor = UIColor.white
self.thePicker.datePickerMode = UIDatePickerMode.date
// dateIssueTextField.inputView = thePicker
// dueDateTextField.inputView = thePicker
textField.inputView = thePicker
// ToolBar
let toolbar = AccessoryToolbar(for: textField)
// let's not forget to set the delegate
toolbar.accessoryDelegate = self
}
override func viewDidLoad() {
super.viewDidLoad()
setUpTextFieldPicker(textField: dateIssueTextField)
setUpTextFieldPicker(textField: dueDateTextField)
}
}