用Swift初始化CLCircularRegion

Question

我对iOS的编程相当陌生，并且正在自学如何使用Swift。我需要为我正在为一堂课制作的应用程序设置地理位置。我的问题是在初始化CLCircularRegion时，我会得到一个错误，上面写着“使用未声明的类型'center'”。我跟踪了苹果开发者网站的文件，不知道我做错了什么。任何帮助都将不胜感激。谢谢。

import UIKit
import MapKit
import CoreLocation

class ViewController: UIViewController, MKMapViewDelegate, CLLocationManagerDelegate {

@IBOutlet var mapView: MKMapView!

var manager = CLLocationManager()

@IBAction func startMonitoring(sender: AnyObject) {
    // 43.039278, -87.932479 mccormick hall location
    var latitude:CLLocationDegrees = 43.039278
    var longitude:CLLocationDegrees = -87.932479
    var center:CLLocationCoordinate2D = CLLocationCoordinate2DMake(latitude, longitude)
    var radius:CLLocationDistance = CLLocationDistance(10.0)
    var identifier:String = "vicmic"

    var geoRegion:CLCircularRegion = CLCircularRegion(center: center, radius: radius, identifier: identifier)

}


override func viewDidLoad() {
    super.viewDidLoad()

    // Core Location
    manager.delegate = self
    manager.desiredAccuracy = kCLLocationAccuracyBest
    manager.requestWhenInUseAuthorization()
    manager.startUpdatingLocation()

}

override func didReceiveMemoryWarning() {
    super.didReceiveMemoryWarning()
    // Dispose of any resources that can be recreated.
}


}

Answer 1

大致上..。代码看起来没问题

1)尝试在类型注释之前保留空格，例如从var center:CLLocationCoordinate2D到此var center: CLLocationCoordinate2D和

2)尝试清理您的DerivedData，重新启动Xcode。