Current Place

Using the Places SDK for iOS, you can discover the place where the device is currently located. That is, the place at the device's currently-reported location. Examples of places include local businesses, points of interest, and geographic locations.

  1. Request location authorization
  2. Usage limits
  3. Get the current location
  4. Display attributions in your app

Requesting location authorization

If your app uses GMSPlacesClient findPlaceLikelihoodsFromCurrentLocationWithPlaceFields:, your app must request permission to use location services. Add the NSLocationWhenInUseUsageDescription key to your Info.plist file, to define the string informing the user why you need the location services. For example:

<key>NSLocationWhenInUseUsageDescription</key>
<string>Show your location on the map</string>

If you want to call findPlaceLikelihoodsFromCurrentLocationWithPlaceFields: when the app is in the background, without triggering a confirmation dialog, take the following steps prior to making the call:

  1. Add the NSLocationAlwaysUsageDescription key to your Info.plistfile.
  2. Call requestAlwaysAuthorization on any instance of CLLocationManager before calling the method.

Request authorization from CLLocationManager as follows:

Swift

    locationManager.requestAlwaysAuthorization()

Objective-C

    [self.locationManager requestAlwaysAuthorization];

Getting the current location

To find the local business or other place where the device is currently located, call GMSPlacesClient findPlaceLikelihoodsFromCurrentLocationWithPlaceFields:. Include the following parameters:

  • One or more GMSPlaceFields, specifying which data types to return. If you omit this parameter, ALL possible fields will be returned, and you will be billed accordingly. This applies only to Place Details requests.
  • A callback method to handle the results.

Fields correspond to Place Search results, and are divided into three billing categories: Basic, Contact, and Atmosphere. Basic fields are billed at base rate, and incur no additional charges. Contact and Atmosphere fields are billed at a higher rate. For more information about how Place data requests are billed, see Usage and Billing.

The API invokes the specified callback method, returning an array of GMSPlaceLikelihood objects.

Each GMSPlaceLikelihood object represents a place. For each place, the result includes an indication of the likelihood that the place is the right one. A higher value means a greater probability that the place is the best match. The buffer may be empty, if there is no known place corresponding to the device location.

The following code sample retrieves the list of places where the device is most likely to be located, and logs the name and likelihood for each place.

Swift

// Specify the place data types to return.
let fields: GMSPlaceField = GMSPlaceField(rawValue: UInt(GMSPlaceField.name.rawValue) |
                                          UInt(GMSPlaceField.placeID.rawValue))!
placesClient?.findPlaceLikelihoodsFromCurrentLocation(withPlaceFields: fields, callback: {
  (placeLikelihoodList: Array<GMSPlaceLikelihood>?, error: Error?) in
  if let error = error {
    print("An error occurred: \(error.localizedDescription)")
    return
  }

  if let placeLikelihoodList = placeLikelihoodList {
    for likelihood in placeLikelihoodList {
      let place = likelihood.place
      print("Current Place name \(String(describing: place.name)) at likelihood \(likelihood.likelihood)")
      print("Current PlaceID \(String(describing: place.placeID))")
    }
  }
})

Objective-C

// Specify the place data types to return.
GMSPlaceField fields = (GMSPlaceFieldName | GMSPlaceFieldPlaceID);
[_placesClient findPlaceLikelihoodsFromCurrentLocationWithPlaceFields:fields callback:^(NSArray<GMSPlaceLikelihood *> * _Nullable likelihoods, NSError * _Nullable error) {
  if (error != nil) {
    NSLog(@"An error occurred %@", [error localizedDescription]);
    return;
  }
  if (likelihoods != nil) {
    for (GMSPlaceLikelihood *likelihood in likelihoods) {
      GMSPlace *place = likelihood.place;
      NSLog(@"Current place name: %@", place.name);
      NSLog(@"Place ID: %@", place.placeID);
    }
  }
}];

Notes about the likelihood values:

  • The likelihood provides a relative probability of the place being the best match within the list of returned places for a single request. You can't compare likelihoods across different requests.
  • The value of the likelihood will be between 0 and 1.0.
  • The sum of the likelihoods in a returned array of GMSPlaceLikelihood objects is always less than or equal to 1.0. Note that the sum isn't necessarily 1.0.

For example, to represent a 55% likelihood that the correct place is Place A, and a 35% likelihood that it's Place B, the likelihood array has two members: Place A with a likelihood of 0.55 and Place B with a likelihood of 0.35.

Displaying attributions in your app

When your app displays information obtained from GMSPlacesClient findPlaceLikelihoodsFromCurrentLocationWithPlaceFields:, the app must also display attributions. Read more about attributions.