Xcode error when using tap gesture recognizer - ios

Question

I start following the Swift tutorial offerred by Apple. In one step using the tap gesture recognizer. When tapping the image, should link to the photoLibrary. But instead, the following message show:
I have used the sample code by the official answer and the same problem pops up. So I guess it is not the code issue?

Answer 1

Not sure, but if the error is because of tap gesture. You can try that :
let enableTap = UITapGestureRecognizer(target: self, action: #selector(self.handleTap(_:)))
view.addGestureRecognizer(enableTap)
view.userInteractionEnabled = true
func handleTap(_ sender: UITapGestureRecognizer) {
print("Success!!!")
}

Answer 2

My code: (sorry it is too long for replying in comment)
import UIKit
class ViewController: UIViewController, UITextFieldDelegate, UIImagePickerControllerDelegate, UINavigationControllerDelegate {
// MARK: Properties
#IBOutlet weak var nameTextField: UITextField!
#IBOutlet weak var mealNameLabel: UILabel!
#IBOutlet weak var photoImageView: UIImageView!
override func viewDidLoad()
{
super.viewDidLoad()
// Handle the text field’s user input through delegate callbacks.
nameTextField.delegate = self
}
/*override func didReceiveMemoryWarning()
{
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
} */
// MARK: UITextFieldDelegate
func textFieldShouldReturn(_ textField: UITextField) -> Bool
{
// Hide the keyboard.
textField.resignFirstResponder()
return true
}
func textFieldDidEndEditing(_ textField: UITextField)
{
mealNameLabel.text = textField.text
}
// MARK: UIImagePickerControllerDelegate
func imagePickerControllerDidCancel(_ picker: UIImagePickerController)
{
// Dismiss the picker if the user canceled.
dismiss(animated: true, completion: nil)
}
func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [String : Any])
{
// The info dictionary may contain multiple representations of the image. You want to use the original.
guard let selectedImage = info[UIImagePickerControllerOriginalImage] as? UIImage
else
{
fatalError("Expected a dictionary containing an image, but was provided the following: \(info)")
}
// Set photoImageView to display the selected image.
photoImageView.image = selectedImage
// Dismiss the picker
dismiss(animated: true, completion: nil)
}
// MARK: Actions
#IBAction func setDefaultLabelText(_ sender: UIButton)
{
mealNameLabel.text = "Default Text"
}
#IBAction func selectImageFromPhotoLibrary(_ sender: Any)
{
// Hide the keyboard
nameTextField.resignFirstResponder()
// UIImagePickerController is a view controller that lets a user pick media from their photo library.
let imagePickerController = UIImagePickerController()
// Only allow photos to be picked, not taken.
imagePickerController.sourceType = .photoLibrary
// The type of imagePickerController.sourceType is known to be UIImagePickerControllerSourceType, which is an enumeration. This means you can write its value as the abbreviated form .photoLibrary instead of UIImagePickerControllerSourceType.photoLibrary.
// Make sure ViewController is notified when the user picks an image.
imagePickerController.delegate = self
present(imagePickerController, animated: true, completion: nil)
}
}

Answer 3

Try this one
let tap = UITapGestureRecognizer(target: self, action: Selector("handleTap:"))
tap.delegate = self
myView.addGestureRecognizer(tap)
Then, you should implement the handler, which will be called each time when a tap event occurs:
func handleTap(sender: UITapGestureRecognizer? = nil) {
// handling code
}
So now calling your tap gesture recognizer event handler is as easy as calling a method handleTap()