UITextFieldShouldChange가 두 번 호출됨 (UITextFieldShouldChange being called twice)

문제 설명

UITextFieldShouldChange가 두 번 호출됨 (UITextFieldShouldChange being called twice)

지도 위에 UIVisualEffectsView를 사용하여 텍스트 필드에 항목이 없는 경우 MKMapView를 흐리게 처리하고 싶습니다. shouldChangeCharactersInRange는 누군가가 입력을 시작할 때 두 번 호출되고 사용자가 UITextField에서 모든 텍스트를 제거할 때는 전혀 호출되지 않습니다. 여기 내 코드

import UIKit
import MapKit
import Parse

class HomeAddressViewController: UIViewController, MKMapViewDelegate, CLLocationManagerDelegate, UITextFieldDelegate {

let locationManager = CLLocationManager()

@IBOutlet var activityIndicator: UIActivityIndicatorView!
@IBOutlet var homeAddressField: UITextField!
@IBOutlet var homeAddressMap: MKMapView!
@IBOutlet var blurryMap: UIVisualEffectView! = UIVisualEffectView()
override func viewDidLoad() {
    super.viewDidLoad()

    activityIndicator.hidden = true

    homeAddressField.delegate = self

    locationManager.delegate = self
    locationManager.desiredAccuracy = kCLLocationAccuracyBest
    locationManager.requestWhenInUseAuthorization()
    locationManager.startUpdatingLocation()

    blurAndUnblurMap()


}
func blurAndUnblurMap() {
    if homeAddressField.text?.characters.count == 0 {
        UIView.animateWithDuration(1, animations: {
            self.blurryMap.effect = UIBlurEffect(style: .Light)
        })
    } else {
        UIView.animateWithDuration(0.5, animations: {
            self.blurryMap.effect = nil
        })
    }
}

func textField(textField: UITextField, shouldChangeCharactersInRange range: NSRange, replacementString string: String) ‑> Bool {
    blurAndUnblurMap()
    return true
}
}

참조 솔루션

방법 1:

Why don't you do this instead?

homeAddressField.addTarget(self, "someFunction:", forControlEvents: .EditingChanged)

Get text changes and act accordingly.

(by Eli、Peyman)

참조 문서

1. UITextFieldShouldChange being called twice (CC BY‑SA 2.5/3.0/4.0)