I have a subclass of UITextField
that is specific to handle Date text. I have a tableviewcell
that uses this text field:
let dateInput: DateTextField
Now the controller needs to initialize the text of the dateInput
prior to display as follows:
cell.dateInput.text = "01/29/2016"
Now, I want to be able to detect that the text changed from the subclass so that I can update the internal date variable so that is it in-sync with the text.
I implemented the textfield delegate methods but that just catches changes made by the user and not programmatically.
You can override property and add didSet
observer in your custom class:
class DateTextField: UITextField {
override var text: String? {
didSet {
// Do your stuff here
}
}
}
My solution for this is to have each instance of the subclass maintain its own notification for UITextFieldDidChange
and use a custom protocol to relay that information to the listener.
protocol MutableTextFieldDelegate {
func textChanged(_ sender:MutableTextField)
}
class MutableTextField : UITextField {
var textChangedDelegate : MutableTextFieldDelegate?
var previousValue : String?
override func awakeFromNib() {
super.awakeFromNib()
NotificationCenter.default.addObserver(forName: .UITextFieldTextDidChange, object: self, queue: nil) { [weak self] notification in
guard let strongSelf = self else { return }
guard let object = notification.object as? MutableTextField, object == strongSelf else { return }
if strongSelf.previousValue != strongSelf.text {
strongSelf.textChangedDelegate?.textChanged(strongSelf)
}
strongSelf.previousValue = strongSelf.text
}
}
}
swift5: NotificationCenter.default.addObserver(forName: UITextField.textDidChangeNotification
...
If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
Donate Us With