iOS UITextField Delegate Actions when a user has started/ended interacting with a textfield
Example
For Swift 3.1:
In the first example one can see how you would intercept the user interacting with a textfield while writing. Similarly, there are methods in the UITextFieldDelegate that are called when a user has started and ended his interaction with a TextField.
To be able to access these methods, you need to conform to the UITextFieldDelegate protocol, and for each textfield you want to be notified about, assign the parent class as the delegate:
class SomeClass: UITextFieldDelegate {
@IBOutlet var textField: UITextField!
override func viewDidLoad() {
super.viewDidLoad()
textField.delegate = self
}
}
Now you will be able to implement all the UITextFieldDelegate methods.
To be notified when a user has started editing a textfield, you can implement textFieldDidBeginEditing(_:) method like so:
func textFieldDidBeginEditing(_ textField: UITextField) {
// now you can perform some action
// if you have multiple textfields in a class,
// you can compare them here to handle each one separately
if textField == emailTextField {
// e.g. validate email
}
else if textField == passwordTextField {
// e.g. validate password
}
}
Similarly, being notified if a user has ended interaction with a textfield, you can use the textFieldDidEndEditing(_:) method like so:
func textFieldDidEndEditing(_ textField: UITextField) {
// now you can perform some action
// if you have multiple textfields in a class,
// you can compare them here to handle each one separately
if textField == emailTextField {
// e.g. validate email
}
else if textField == passwordTextField {
// e.g. validate password
}
}
If you want to have control over whether a TextField should begin/end editing, the textFieldShouldBeginEditing(_:) and textFieldShouldEndEditing(_:) methods can be used by return true/false based on your needed logic.
