How to draw routes between two locations in google maps iOS swift - ios

Question

I'm using google maps in my iOS swift project. I want to draw a path between two locations on the map (Not straight line). Any idea how to do that ?

Answer 1

To draw polyline between two locations on Google Map in Swift.
//Pass your source and destination coordinates in this method.
func fetchRoute(from source: CLLocationCoordinate2D, to destination: CLLocationCoordinate2D) {
let session = URLSession.shared
let url = URL(string: "http://maps.googleapis.com/maps/api/directions/json?origin=\(source.latitude),\(source.longitude)&destination=\(destination.latitude),\(destination.longitude)&sensor=false&mode=driving")!
let task = session.dataTask(with: url, completionHandler: {
(data, response, error) in
guard error == nil else {
print(error!.localizedDescription)
return
}
guard let jsonResponse = try? JSONSerialization.jsonObject(with: data!, options: .allowFragments) as? [String: Any] else {
print("error in JSONSerialization")
return
}
guard let routes = jsonResponse["routes"] as? [Any] else {
return
}
guard let route = routes[0] as? [String: Any] else {
return
}
guard let overview_polyline = route["overview_polyline"] as? [String: Any] else {
return
}
guard let polyLineString = overview_polyline["points"] as? String else {
return
}
//Call this method to draw path on map
self.drawPath(from: polyLineString)
})
task.resume()
}
To draw polyline on map .
func drawPath(from polyStr: String){
let path = GMSPath(fromEncodedPath: polyStr)
let polyline = GMSPolyline(path: path)
polyline.strokeWidth = 3.0
polyline.map = mapView // Google MapView
}

Answer 2

Showing Multiple-routes between two locations in google maps in swift 3.0 with camera zoom:
let origin = "\(startLocation.coordinate.latitude),\(startLocation.coordinate.longitude)"
let destination = "\(destinationLocation.coordinate.latitude),\(destinationLocation.coordinate.longitude)"
let urlString = "https://maps.googleapis.com/maps/api/directions/json?origin=\(origin)&destination=\(destination)&mode=driving&key=API_KEY"
let url = URL(string: urlString)
URLSession.shared.dataTask(with: url!, completionHandler: {
(data, response, error) in
if(error != nil){
print("error")
}else{
do{
let json = try JSONSerialization.jsonObject(with: data!, options:.allowFragments) as! [String : AnyObject]
let routes = json["routes"] as! NSArray
self.mapView.clear()
OperationQueue.main.addOperation({
for route in routes
{
let routeOverviewPolyline:NSDictionary = (route as! NSDictionary).value(forKey: "overview_polyline") as! NSDictionary
let points = routeOverviewPolyline.object(forKey: "points")
let path = GMSPath.init(fromEncodedPath: points! as! String)
let polyline = GMSPolyline.init(path: path)
polyline.strokeWidth = 3
let bounds = GMSCoordinateBounds(path: path!)
self.mapView!.animate(with: GMSCameraUpdate.fit(bounds, withPadding: 30.0))
polyline.map = self.mapView
}
})
}catch let error as NSError{
print("error:\(error)")
}
}
}).resume()

Answer 3

Above all answers can draw routes but there is a way that you can draw accurate route using directions API.Here is the code hopefully it will help for you.
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=\(source.latitude),\(source.longitude)&destination=\(destination.latitude),\(destination.longitude)&sensor=false&mode=driving&key=\(Your_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()
}
And then
//MARK:- Draw Path line
func drawPath(from polyStr: String){
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: sourceLocationCordinates, coordinate: destinationLocationCordinates))
mapView.moveCamera(cameraUpdate)
let currentZoom = mapView.camera.zoom
mapView.animate(toZoom: currentZoom - 1.4)
}
Note: I have added sourcesLocationCordinates and destinationLocationCordinates variables.Don't forget to replace them with your source and destination.Hopefully this will help you making perfect route line.

Answer 4

Create a new Swift file copy this code, that's it call then drawPolygon() method from map view for polygon line.
import GoogleMaps
private struct MapPath : Decodable{
var routes : [Route]?
}
private struct Route : Decodable{
var overview_polyline : OverView?
}
private struct OverView : Decodable {
var points : String?
}
extension GMSMapView {
//MARK:- Call API for polygon points
func drawPolygon(from source: CLLocationCoordinate2D, to destination: CLLocationCoordinate2D){
let config = URLSessionConfiguration.default
let session = URLSession(configuration: config)
guard let url = URL(string: "https://maps.googleapis.com/maps/api/directions/json?origin=\(source.latitude),\(source.longitude)&destination=\(destination.latitude),\(destination.longitude)&sensor=false&mode=driving") else {
return
}
DispatchQueue.main.async {
session.dataTask(with: url) { (data, response, error) in
guard data != nil else {
return
}
do {
let route = try JSONDecoder().decode(MapPath.self, from: data!)
if let points = route.routes?.first?.overview_polyline?.points {
self.drawPath(with: points)
}
print(route.routes?.first?.overview_polyline?.points)
} catch let error {
print("Failed to draw ",error.localizedDescription)
}
}.resume()
}
}
//MARK:- Draw polygon
private func drawPath(with points : String){
DispatchQueue.main.async {
let path = GMSPath(fromEncodedPath: points)
let polyline = GMSPolyline(path: path)
polyline.strokeWidth = 3.0
polyline.strokeColor = .red
polyline.map = self
}
}
}

Answer 5

This piece of code will work right for you. Don't forget to change your API key and mode (walking, driving).
func draw(src: CLLocationCoordinate2D, dst: CLLocationCoordinate2D){
let config = URLSessionConfiguration.default
let session = URLSession(configuration: config)
let url = URL(string: "https://maps.googleapis.com/maps/api/directions/json?origin=\(src.latitude),\(src.longitude)&destination=\(dst.latitude),\(dst.longitude)&sensor=false&mode=walking&key=**YOUR_KEY**")!
let task = session.dataTask(with: url, completionHandler: {
(data, response, error) in
if error != nil {
print(error!.localizedDescription)
} else {
do {
if let json : [String:Any] = try JSONSerialization.jsonObject(with: data!, options: .allowFragments) as? [String: Any] {
let preRoutes = json["routes"] as! NSArray
let routes = preRoutes[0] as! NSDictionary
let routeOverviewPolyline:NSDictionary = routes.value(forKey: "overview_polyline") as! NSDictionary
let polyString = routeOverviewPolyline.object(forKey: "points") as! String
DispatchQueue.main.async(execute: {
let path = GMSPath(fromEncodedPath: polyString)
let polyline = GMSPolyline(path: path)
polyline.strokeWidth = 5.0
polyline.strokeColor = UIColor.green
polyline.map = mapView
})
}
} catch {
print("parsing error")
}
}
})
task.resume()
}