我正在开发一个应用程序,其中有一个视图控制器和子视图。在子视图上我正在加载谷歌地图,在主视图上我有一个标签。
我的问题是如何将数据从子视图(地图地理位置)传递到主视图上的标签,并在使用 Swift 更新位置时更新该数据。
我发现的所有教程都使用prepareForSegue,我想在主视图上自动更新标签。
Thanks
更新:我似乎无法让委托方法发挥作用。代码如下。
MapChildController.swift
import UIKit
protocol ChildViewControllerDelegate{
func delegateMethod(childViewController:MapChildController, text:String)
}
class MapChildController: UIViewController, CLLocationManagerDelegate {
@IBOutlet weak var mapView: GMSMapView!
let locationManager = CLLocationManager()
var didFindMyLocation = false
var myLocations: [CLLocation] = []
var delegate:ChildViewControllerDelegate?
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view, typically from a nib.
var camera = GMSCameraPosition.cameraWithLatitude(-33.86, longitude: 151.20, zoom: 15, bearing: 0, viewingAngle: 45)
var mapView = GMSMapView.mapWithFrame(CGRectZero, camera: camera)
mapView.myLocationEnabled = true
self.view = mapView
locationManager.delegate = self
locationManager.distanceFilter = kCLDistanceFilterNone
locationManager.desiredAccuracy = kCLLocationAccuracyBest
if NSProcessInfo().isOperatingSystemAtLeastVersion(NSOperatingSystemVersion(majorVersion: 8, minorVersion: 0, patchVersion: 0)) {
println("iOS >= 8.0.0")
locationManager.requestWhenInUseAuthorization()
//locationManager.requestAlwaysAuthorization()
}
mapView.addObserver(self, forKeyPath: "myLocation", options: NSKeyValueObservingOptions.New, context: nil)
locationManager.startUpdatingLocation()
//locationManager.startMonitoringSignificantLocationChanges()
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
override func observeValueForKeyPath(keyPath: String, ofObject object: AnyObject, change: [NSObject : AnyObject], context: UnsafeMutablePointer<Void>) {
if !didFindMyLocation {
let myLocation: CLLocation = change[NSKeyValueChangeNewKey] as! CLLocation
var mapView = self.view as! GMSMapView
mapView.camera = GMSCameraPosition.cameraWithTarget(myLocation.coordinate, zoom: 15.0)
mapView.settings.myLocationButton = true
didFindMyLocation = true
}
}
func locationManager(manager:CLLocationManager, didUpdateLocations locations:[AnyObject]) {
// println("Last location: \(locations.last)")
self.delegate?.delegateMethod(self, text: "from child")
}
}
地图控制器.swift
import Foundation
import UIKit
class MapController : UIViewController, ChildViewControllerDelegate
{
@IBOutlet weak var Label: UILabel!
var LabelText = String()
override func viewDidLoad() {
super.viewDidLoad()
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
func delegateMethod(controller: MapChildController, text: String) {
println("The text is " + text);
}
}