Map Update

In this guide, you will learn how to download and apply updates to maps.

The assets directory includes a world map file and a map for Andorra that are used in this example.

Setup

First, get an API key token, see the Getting Started guide.

Prerequisites

Make sure you completed the Environment Setup - Flutter Examples guide before starting this guide.

Build and Run

Start a terminal/command prompt and navigate to the map_update directory within the Flutter examples directory. This is the name of the example project.

Note - the gem_kit directory containing the Maps SDK for Flutter should be in the plugins directory of the example, e.g. example_pathname/plugins/gem_kit - see the environment setup guide above.

Run: flutter pub get

Configure the native parts:

Android

First, verify that the ANDROID_SDK_ROOT environment variable is set to the root path of your android SDK.

In android/build.gradle add the maven block as shown, within the allprojects block, for both debug and release builds:

    allprojects {
        repositories {
            google()
            mavenCentral()
            maven {
               url "${rootDir}/../plugins/gem_kit/android/build"
            }
        }
    }

in android/app/build.gradle within the android block, in the defaultConfig block, the android SDK version minSdk must be set as shown below.

Additionally, for release builds, in android/app/build.gradle, within the android block, add the buildTypes block as shown:

Replace example_pathname with the actual project pathname

android {
    defaultConfig {
        applicationId "com.magiclane.gem_kit.examples.example_pathname"
        minSdk 21
        targetSdk flutter.targetSdk
        versionCode flutterVersionCode.toInteger()
        versionName flutterVersionName
    }
    buildTypes {
        release {
            minifyEnabled false
            shrinkResources false

            // TODO: Add your own signing config for the release build.
            // Signing with the debug keys for now, so `flutter run --release` works.
            signingConfig signingConfigs.debug
        }
    }
}

iOS

In the ios/Podfile configuration file, at the top, set the minimum ios platform version to 14 like this:

platform :ios, '14.0'

We recommend you to run these commands after you copy the gem_kit into your project: flutter clean flutter pub get and cd ios pod install

Then run the project:

flutter run --debug

or

flutter run --release

How it Works

This example demonstrates how to simulate an map update. It replaces the default map in the app with the one in the assets, which is an older version and needs to be updated, then applies the logic for updating the map.

Import Necessary Packages

First, import the required packages in your Dart code.

import 'maps_page.dart';
import 'package:gem_kit/content_store.dart';
import 'package:gem_kit/core.dart';
import 'package:gem_kit/map.dart';
import 'package:map_update/update_persistence.dart';
import 'package:path/path.dart' as path;
import 'package:path_provider/path_provider.dart';
import 'package:flutter/material.dart';
import 'package:flutter/services.dart';
import 'dart:io';

Initialize GemKit

In the main function, initialize GemKit with your project API token.

void main() {
  const projectApiToken = String.fromEnvironment('GEM_TOKEN');

  GemKit.initialize(appAuthorization: projectApiToken).then((value) {
    SdkSettings.setAllowConnection(true, onWorldwideRoadMapSupportStatusCallback: (status) {
      print("UpdatePersistence: onWorldwideRoadMapSupportStatus $status");
      if (status != Status.upToDate) {
        UpdatePersistence.instance.isOldData = true;
      }
    });
    SdkSettings.appAuthorization = projectApiToken;
  });

  runApp(const MyApp());
}

UI and Map Integration

class MyApp extends StatelessWidget {
  const MyApp({super.key});

  @override
  Widget build(BuildContext context) {
    return const MaterialApp(
      debugShowCheckedModeBanner: false,
      title: 'Map Update',
      home: MyHomePage(),
    );
  }
}

class MyHomePage extends StatefulWidget {
  const MyHomePage({super.key});
  @override
  State<MyHomePage> createState() => _MyHomePageState();
}

Handle the map update logic and UI

Within _MyHomePageState, define the necessary state variables and methods to interact with the map and manage updates.

}

Flutter Examples

Maps SDK for Flutter Examples can be downloaded or cloned with Git