Fetching nearby places using google maps

问题:

Am trying to implement to find nearby places of my current location using google maps. I have created a project in Google Developer Console and got 'ios APIkey' and 'Server APIkey'. I also enabled Google Places API and Google Maps SDK for iOS. Below is the code to find out near by places.

func fetchPlacesNearCoordinate(coordinate: CLLocationCoordinate2D, radius: Double, name : String){
    var urlString = "https://maps.googleapis.com/maps/api/place/nearbysearch/json?key=\(apiServerKey)&location=\(coordinate.latitude),\(coordinate.longitude)&radius=\(radius)&rankby=prominence&sensor=true"
    urlString += "&name=\(name)"

    urlString = urlString.stringByAddingPercentEscapesUsingEncoding(NSUTF8StringEncoding)!
    println(urlString)
    if placesTask.taskIdentifier > 0 && placesTask.state == .Running {
        placesTask.cancel()

    }
    UIApplication.sharedApplication().networkActivityIndicatorVisible = true
    placesTask = session.dataTaskWithURL(NSURL(string: urlString)!) {data, response, error in
        println("inside.")
        UIApplication.sharedApplication().networkActivityIndicatorVisible = false
        if let json = NSJSONSerialization.JSONObjectWithData(data, options:nil, error:nil) as? NSDictionary {
            if let results = json["results"] as? NSArray {
                for rawPlace:AnyObject in results {
                    println(rawPlace)
                    self.results.append(rawPlace as! String)
                }
            }
        }
            self.placesTask.resume()
    }
}

The passed coordinate is current location's coordinate. If I execute a above code, nothing is happening but generated url is valid one. If i put that url in Google am getting correct results. But nothing displaying in my app. Please help me to resolve this. and please let me know where am wrong!!!

回答1:

You add your places to the results array, but you have done anything to update your mapview, for example, adding markers to your mapview.

sample code add marker to mapview:

   let returnedPlaces: NSArray? = jsonResult["results"] as? NSArray

  if returnedPlaces != nil {

           for index in 0..<returnedPlaces!.count {

                 if let returnedPlace = returnedPlaces?[index] as? NSDictionary {

                       var placeName = ""
                       var latitude = 0.0
                       var longitude = 0.0

                       if let name = returnedPlace["name"] as? NSString {
                           placeName = name as String
                       }

                       if let geometry = returnedPlace["geometry"] as? NSDictionary {
                           if let location = geometry["location"] as? NSDictionary {
                                 if let lat = location["lat"] as? Double {
                                            latitude = lat
                                 }

                                 if let lng = location["lng"] as? Double {
                                           longitude = lng
                                  }
                            }
                       }

                       let marker = GMSMarker()
                       marker.position = CLLocationCoordinate2DMake(latitude, longitude)
                       marker.title = placeName
                       marker.map = self.mapView
                }
           }
   }

You can see this tutorial about how to get nearby places with Google Maps in Swift.

回答2:

Just set your Latt, long and GoogleAPIKey.

NSString *urlString= [NSString stringWithFormat:@"https://maps.googleapis.com/maps/api/place/nearbysearch/json?location=%@,%@&radius=2000&key=%@",lati,longi,kGoogleAPIKey];
[NSURLConnection sendAsynchronousRequest:[NSURLRequest requestWithURL:[NSURL URLWithString:urlString]] queue:[NSOperationQueue mainQueue] completionHandler:^(NSURLResponse *response, NSData *data, NSError *connectionError)
     {
         if (connectionError)
         {
             NSLog(@"Error");
         }
         else
         {
             NSDictionary *dictJson = [NSJSONSerialization JSONObjectWithData:data options:NSJSONReadingAllowFragments error:nil];
             NSArray *arrayPlaces = [[NSArray alloc] initWithArray:[dictJson objectForKey:@"results"]];
             NSLog("Place %@",arrayPlaces);

         }
     }];

Moreover, if you want to search place by text, Just make urlString as below.

  NSString *urlString = [NSString stringWithFormat:@"https://maps.googleapis.com/maps/api/place/autocomplete/json?sensor=true&key=%@&language=en&input=%@&query=123+main+street&radius=50000&location=0.0,0.0&rankby=distance",kGoogleAPIKey,searchText];

In arrayPlaces you have nearby places.