我正在尝试创建一个应用，您可以从Web API获取总线位置。当我得到数据时，我在mapview上为我从API获得的所有坐标添加了注释。然后，当点击注释时，我试图隐藏所有注释，这些注释与点击的注释不在同一条路线上。它工作正常，但是当我缩小原始区域中没有隐藏的注释时。有没有办法刷新用户放大地图视图时显示的内容？
import UIKit
import MapKit
import MBProgressHUD
import Alamofire
class MapViewController: UIViewController {
//MARK: Properties and Outlets
private var timer: NSTimer?
private lazy var dateFormatter = NSDateFormatter()
private var vehicles = [String: Vehicle]()
private var points = [CLLocationCoordinate2D]()
private let locationManager = CLLocationManager()
private var currentLocation: CLLocation?
@IBOutlet weak var mapView: MKMapView!
//MARK: Actions
@IBAction func getMyLocation(sender: UIBarButtonItem) {
getLocation()
}
//MARK: Life Cycle
override func viewDidLoad() {
super.viewDidLoad()
dateFormatter.locale = NSLocale.currentLocale()
dateFormatter.dateFormat = "HH:mm:ss"
timer = NSTimer.scheduledTimerWithTimeInterval(30, target: self, selector: "fetchVehiclesLocations", userInfo: nil, repeats: true)
fetchVehiclesLocations()
getLocation()
}
//MARK: Get Location
private func getLocation() {
let authStatus = CLLocationManager.authorizationStatus()
if authStatus == .NotDetermined {
locationManager.requestWhenInUseAuthorization()
return
}
if authStatus == .Denied || authStatus == .Restricted {
showLocationServicesDeniedAlert()
return
}
startLocationManager()
}
//MARK: Helper methods
private func showLocationServicesDeniedAlert() {
let alert = UIAlertController(title: "Location Services Disabled", message: "Please enable location services for this app in Settings.", preferredStyle: .Alert)
let okAction = UIAlertAction(title: "OK", style: .Default, handler: nil)
alert.addAction(okAction)
presentViewController(alert, animated: true, completion: nil)
}
private func startLocationManager () {
if CLLocationManager.locationServicesEnabled() {
locationManager.delegate = self
locationManager.desiredAccuracy = kCLLocationAccuracyNearestTenMeters
locationManager.startUpdatingLocation()
showLoadingHUD()
}
}
private func stopLocationManager() {
locationManager.delegate = nil
locationManager.stopUpdatingLocation()
hideLoadingHUD()
}
private func rotateBus() {
UIView.animateWithDuration(1.0, delay: 0, options: .CurveLinear, animations: {
for (id, _) in self.vehicles {
if self.vehicles[id]!.lastPosition != nil {
let annotationView = self.mapView.viewForAnnotation(self.vehicles[id]!.annotation!)
let currentLocationPoint = self.mapView.convertCoordinate(self.vehicles[id]!.lastPosition!, toPointToView: self.mapView)
let destinationPoint = self.mapView.convertCoordinate(self.vehicles[id]!.coordinates, toPointToView: self.mapView)
let yDiff = currentLocationPoint.y - destinationPoint.y
let xDiff = destinationPoint.x - currentLocationPoint.x
let arcTan = atan(yDiff / xDiff)
var angle = CGFloat(M_PI / 2) - arcTan
if xDiff < 0 {
angle = angle + CGFloat(M_PI)
}
if angle.isNaN || angle == 0.0 {
continue
}
else {
annotationView?.transform = CGAffineTransformMakeRotation(CGFloat(angle))
}
}
}
}, completion: nil)
moveBus()
}
private func moveBus() {
UIView.animateWithDuration(28.0, delay: 0, options: .CurveLinear, animations: {
for(id, _) in self.vehicles {
if self.vehicles[id]!.lastPosition != nil {
self.vehicles[id]!.annotation?.coordinate = self.vehicles[id]!.coordinates
}
}
}, completion: nil)
}
private func createVehicles() {
print(vehicles.count)
for (id, _) in vehicles {
if vehicles[id]?.annotation == nil {
let annotation = BusAnnotation()
annotation.imageName = "bus"
annotation.coordinate = vehicles[id]!.coordinates
annotation.title = id
vehicles[id]?.annotation = annotation
mapView.addAnnotation(annotation)
}
}
print(mapView.annotations.count)
rotateBus()
}
private func drawPolyline() {
let myPolyline = MKPolyline(coordinates: &points, count: points.count)
mapView.addOverlay(myPolyline)
}
//MARK: HUD display methods
private func showLoadingHUD() {
let hud = MBProgressHUD.showHUDAddedTo(mapView, animated: true)
hud.labelText = "Getting Your Location..."
}
private func hideLoadingHUD() {
MBProgressHUD.hideAllHUDsForView(mapView, animated: true)
}
//MARK: Networking
func fetchVehiclesLocations() {
let URL = urlVehiclesLocations + apiKey
if !vehicles.isEmpty {
for (id , _) in vehicles {
vehicles[id]?.lastPosition = vehicles[id]?.coordinates
}
}
Alamofire.request(.GET, URL)
.validate()
.responseJSON {
(request, response, result) in
guard result.isSuccess else {
print("Error while fetching \(result.error!)")
return
}
let value = result.value as? [String: AnyObject]
let responseDict = value?["response"] as? [String: AnyObject]
let array = responseDict?["entity"] as? [[String: AnyObject]]
for var i = 0; i < array?.count; i++ {
let item = array?[i]["vehicle"] as? [String: AnyObject]
let position = item?["position"] as? [String: AnyObject]
let trip = item?["trip"] as? [String: AnyObject]
let vehicle = Vehicle()
vehicle.latitude = position?["latitude"] as! Double
vehicle.longitude = position?["longitude"] as! Double
vehicle.tripId = trip?["trip_id"] as! String
let startTime = trip?["start_time"] as! String
vehicle.startTime = self.dateFormatter.dateFromString(startTime)
let vehicleId = item?["vehicle"] as? [String: AnyObject]
let id = vehicleId?["id"] as! String
if self.vehicles[id] == nil {
self.vehicles[id] = vehicle
}
else {
self.vehicles[id]?.latitude = vehicle.latitude
self.vehicles[id]?.longitude = vehicle.longitude
}
}
self.createVehicles()
}
}
func fetchPointsForTripPolyline() {
let URL = urlTripPolyline + apiKey
Alamofire.request(.GET, URL)
.validate()
.responseJSON {
(request, response, result) in
guard result.isSuccess else {
print("Error while fetching \(result.error!)")
return
}
let value = result.value as! [String: AnyObject]
let responseArray = value["response"] as! [[String: AnyObject]]
for var i = 0; i < responseArray.count; i++ {
let longitude = responseArray[i]["shape_pt_lon"] as! CLLocationDegrees
let latitude = responseArray[i]["shape_pt_lat"] as! CLLocationDegrees
let coordinate = CLLocationCoordinate2D(latitude: latitude, longitude: longitude)
self.points.append(coordinate)
}
self.drawPolyline()
}
}
}
extension MapViewController: CLLocationManagerDelegate {
func locationManager(manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
let newLocation = locations.last!
if newLocation.timestamp.timeIntervalSinceNow < -5 {
return
}
if newLocation.horizontalAccuracy < 0 {
return
}
if newLocation.horizontalAccuracy <= locationManager.desiredAccuracy {
stopLocationManager()
currentLocation = newLocation
let annotation = MKPointAnnotation()
annotation.coordinate = newLocation.coordinate
mapView.addAnnotation(annotation)
}
let center = CLLocationCoordinate2D(latitude: newLocation.coordinate.latitude, longitude: newLocation.coordinate.longitude)
let region = MKCoordinateRegionMakeWithDistance(center, 1000, 1000)
self.mapView.setRegion(region, animated: true)
}
}
extension MapViewController: MKMapViewDelegate {
func mapView(mapView: MKMapView, viewForAnnotation annotation: MKAnnotation) -> MKAnnotationView? {
if !(annotation is BusAnnotation) {
return nil
}
let reuseId = annotation.title!
var busAnnotationView = mapView.dequeueReusableAnnotationViewWithIdentifier(reuseId!)
if busAnnotationView == nil {
busAnnotationView = MKAnnotationView(annotation: annotation, reuseIdentifier: reuseId)
busAnnotationView?.canShowCallout = true
}
else {
busAnnotationView?.annotation = annotation
}
let busAnnotation = annotation as! BusAnnotation
busAnnotationView?.image = UIImage(named: busAnnotation.imageName)
return busAnnotationView
}
func mapView(mapView: MKMapView, rendererForOverlay overlay: MKOverlay) -> MKOverlayRenderer {
if overlay is MKPolyline {
let lineView = MKPolylineRenderer(overlay: overlay)
lineView.lineWidth = 3.0
lineView.strokeColor = UIColor.greenColor()
return lineView
}
return MKOverlayRenderer()
}
func hideBuses(tripId: String) {
for (_, vehicle) in vehicles {
if vehicle.tripId != tripId {
let annotationView = mapView.viewForAnnotation(vehicle.annotation!)
annotationView?.hidden = true
}
}
}
func mapView(mapView: MKMapView, didSelectAnnotationView view: MKAnnotationView) {
let vehicleId = view.annotation?.title!
let tripId = vehicles[vehicleId!]?.tripId
hideBuses(tripId!)
}
}