HERE iOS SDK: Places API make*Request always returns nil

Question

I am new to the Here iOS SDK and I am trying to use the places API by searching for places around a location. I did a pod try HEREMapsStarter and tried the following code:

let places = NMAPlaces()
let location = NMAGeoCoordinates(latitude: yyy, longitude: xxx)

let result2 = places.makeSearchRequest(location: location, query: "restaurant")
let result = places.makeHereRequest(location: location, filters: nil)
result?.start(listener: self)
result2?.start(listener: self)

But this doesn't work because both result and result2 are nil. What am I missing here?

Answer 1

It seems that you are trying to create the places object:

let places = NMAPlaces()

But places object is Singleton and can be retrieved only by calling shared()

let places = NMAPlaces.shared()

Also as you are using result?.start(listener: self) method you need to implement the NMAResultListener listener. Example of simple listener:

class MainViewController: UIViewController, NMAResultListener {

    func requestDidComplete(_ request: NMARequest, data: Any?, error inError: Error?) {
            print("data = \(String(describing: data))")
            guard inError == nil else {
                print ("Request error \((inError! as NSError).code)")
                return
            }
            guard data is NMADiscoveryPage, let resultPage = data as? NMADiscoveryPage else {
                print ("invalid type returned \(String(describing: data))")
                return
            }

            let resultsArray: [NMALink] = resultPage.discoveryResults;
            for link in resultsArray
            {
                if let placeLink = link as? NMAPlaceLink {
                    print("PlaceLink position: \(placeLink.position.latitude), \(placeLink.position.longitude)")
                }
            }
        }
....

}

====================================================================

Let's assume you are searching in UK, London(51.514545,-0.131666) and use NMAResultListener as described above. In both requests the listener parameter self implements NMAResultListener as described above.

The code for makeSearchRequest might be next:

let geoCoordCenter = NMAGeoCoordinates(latitude:51.514545, longitude: -0.131666)
let searchRequest = NMAPlaces.shared().makeSearchRequest(location: geoCoordCenter, query: "restaurant")
searchRequest?.start(listener: self)

When request is finished the makeSearchRequest will return results:

data = Optional(<NMADiscoveryPage: 0x28241a400>)
PlaceLink position: 51.5117, -0.12565
PlaceLink position: 51.51312, -0.13374
....
PlaceLink position: 51.51371, -0.13155
PlaceLink position: 51.51462, -0.12651

And code for makeHereRequest:

let geoCoordCenter = NMAGeoCoordinates(latitude:51.514545, longitude: -0.131666)
let hereRequest = NMAPlaces.shared().makeHereRequest(location: geoCoordCenter, filters: nil)
hereRequest?.start(listener: self)

makeHereRequest will return results:

data = Optional(<NMADiscoveryPage: 0x282400f00>)
PlaceLink position: 51.514542, -0.131883
PlaceLink position: 51.514542, -0.131883
....
PlaceLink position: 51.51435, -0.13169
PlaceLink position: 51.51444, -0.13194
PlaceLink position: 51.51444, -0.13194

Also note that depending on network conditions and the location of search there also might be error result like not found or other errors.