How to draw routes on GMSmap view swift (not straight) using google api Swift - swift

Question

I am trying to draw route on mapview using the google direction API . I am using the solution from the stackoverflow itself but i am getting some errors regarding intializers .
Also will the directions route will be same as google map itself or a straight one .
Any help is Appreciated. Also where should i call this methods
I am getting error as
Cannot invoke initializer for type 'GMSCoordinateBounds' with an argument list of type '(coordinate: String, String, coordinate:
String, String)'
Below is the Code .
func getRouteSteps(from source: CLLocationCoordinate2D, to destination: CLLocationCoordinate2D) {
let session = URLSession.shared
let url = URL(string: "https://maps.googleapis.com/maps/api/directions/json?origin=\(lat),\(long)&destination=\(directionlat),\(directionlong)&sensor=false&mode=driving&key=\(API KEY)")!
let task = session.dataTask(with: url, completionHandler: {
(data, response, error) in
guard error == nil else {
print(error!.localizedDescription)
return
}
guard let jsonResult = try? JSONSerialization.jsonObject(with: data!, options: .allowFragments) as? [String: Any] else {
print("error in JSONSerialization")
return
}
guard let routes = jsonResult!["routes"] as? [Any] else {
return
}
guard let route = routes[0] as? [String: Any] else {
return
}
guard let legs = route["legs"] as? [Any] else {
return
}
guard let leg = legs[0] as? [String: Any] else {
return
}
guard let steps = leg["steps"] as? [Any] else {
return
}
for item in steps {
guard let step = item as? [String: Any] else {
return
}
guard let polyline = step["polyline"] as? [String: Any] else {
return
}
guard let polyLineString = polyline["points"] as? String else {
return
}
//Call this method to draw path on map
DispatchQueue.main.async {
self.drawPath(from: polyLineString)
}
}
})
task.resume()
}
Function to draw polyline
func drawPath(from polyStr: String){
let mapView: GMSMapView
let path = GMSPath(fromEncodedPath: polyStr)
let polyline = GMSPolyline(path: path)
polyline.strokeWidth = 3.0
polyline.map = mapView // Google MapView
//
let cameraUpdate = GMSCameraUpdate.fit(GMSCoordinateBounds(coordinate: "\(lat)","\(long)", coordinate: "\(directionlat)","\(directionlong)")) as? [String : AnyObject]
mapView.moveCamera(cameraUpdate)
let currentZoom = mapView.camera.zoom
mapView.animate(toZoom: currentZoom - 1.4)
}

Answer 1

GMSCoordinatesBounds takes CLLocationCoordinates2D type as parameter, not String.
replace
let cameraUpdate = GMSCameraUpdate.fit(GMSCoordinateBounds(coordinate: "\(lat)","\(long)", coordinate: "\(directionlat)","\(directionlong)")) as? [String : AnyObject]
with
let cameraUpdate = GMSCameraUpdate.fit(GMSCoordinateBounds(coordinate: CLLocationCoordinate2D(latitude: Double(lat), longitude: Double(long)), coordinate: CLLocationCoordinate2D(latitude: Double(directionlat), longitude: Double(directionlat))))
and once you have added the mapView to your view controller and got the coordinates, call your function
self.getRouteSteps(from source: CLLocationCoordinate2D(latitude: Double(lat), longitude: Double(long)), destination: CLLocationCoordinate2D(latitude: Double(directionlat), longitude: Double(directionlat)))

Answer 2

You can try this, use the below to fetch direction:
//This function is used to fetch the directions from origin to destination
private func fetchDirection(destinationLat: CLLocationDegrees, destinationLong: CLLocationDegrees) {
//Here you need to set your origin and destination points and mode
if let location = locationManager.location {
guard let url = URL(string: "\("https://maps.googleapis.com/maps/api/directions/json")?origin=\(location.coordinate.latitude),\(location.coordinate.longitude)&destination=\(destinationLat),\(destinationLong)&key=\(Constants.MapKey)") else { return }
let task = URLSession.shared.dataTask(with: url) { [unowned self](data, response, error) -> Void in
do {
guard let data = data else { return }
let decoder = JSONDecoder()
decoder.keyDecodingStrategy = .convertFromSnakeCase
guard let mapData = try? decoder.decode(MapModel.self, from: data) else { return }
if let points = mapData.routes.first?.overviewPolyline.points {
self.drawRoute(points: points)
}
}
}
task.resume()
}
}
Use this to draw the route on the map:
//This function is used to draw the routes
private func drawRoute(points: String) {
let path = GMSPath.init(fromEncodedPath: points)
let singleLine = GMSPolyline.init(path: path)
self.polylines.append(singleLine)
singleLine.strokeWidth = 6.0
let gradientColor: GMSStrokeStyle = GMSStrokeStyle.gradient(from: .red, to: .blue)
singleLine.spans = [GMSStyleSpan.init(style: gradientColor)]
if self.polylines.count > 0 {
self.polylines.forEach{ $0.map = nil }
}
singleLine.map = self.mapView
}
And, here is the MapModel
struct MapModel: Decodable {
let status: String
let routes: [Routes]
}
struct Routes: Decodable {
let overviewPolyline: OverviewPolyline
}
struct OverviewPolyline: Decodable {
let points: String
}
I hope you are familiar with Codables and also, I have called the drawRoute function when I received the points.