This library provides Google places autocomplete widgets for flutter. It uses google_maps_webservice library which directly refer to the official documentation for google maps web service.

According to https://stackoverflow.com/a/52545293, you need to enable billing on your account, even if you are only using the free quota.

In the dependencies: section of your pubspec.yaml, add the following line:

dependencies:
  flutter_google_places: <latest_version>

const kGoogleApiKey = "API_KEY";
Prediction p = await PlacesAutocomplete.show(
                          context: context,
                          apiKey: kGoogleApiKey,
                          mode: Mode.overlay, // Mode.fullscreen
                          language: "fr",
                          components: [new Component(Component.country, "fr")]);

View the Flutter app in the example directory.