/maps

A Mapbox GL flutter package for creating custom maps

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Flutter Mapbox GL

Please note that this project is community driven and is not an official Mapbox product.

We welcome feedback and contributions.

This Flutter plugin allows to show embedded interactive and customizable vector maps inside a Flutter widget. For the Android and iOS integration, we use mapbox-gl-native. For web, we rely on mapbox-gl-js. This project only supports a subset of the API exposed by these libraries.

screenshot.png

How to use

This project is available on pub.dev, follow the instructions to add a package into your flutter application.

Private Mapbox access token

This project does require a Mapbox access token to download the underlying Android/iOS SDKs. The secret access token must have the Download: read scope for Android and/or iOS.

If this configuration is not present, an error like the following appears during the build process:

Android

* What went wrong:
A problem occurred evaluating project ':mapbox_gl'.
> SDK Registry token is null. See README.md for more information.

iOS

[!] Error installing Mapbox-iOS-SDK
curl: (22) The requested URL returned error: 401 Unauthorized

Public Mapbox access token

Next to a private access token you will need to provide an public access token to retrieve the style and underlying resources. This can be done with running your application with an additional define statement:

flutter run -d {device_id} --dart-define=ACCESS_TOKEN=ADD_YOUR_TOKEN_HERE`

Supported API

Feature Android iOS Web
Style
Camera
Gesture
User Location
Style DSL
Raster Layer
Symbol Layer
Circle Layer
Line Layer
Fill Layer
Hillshade Layer
Heatmap Layer
Vector Source
Raster Source
GeoJson Source
Image Source
Expressions
Symbol Annotation
Circle Annotation
Line Annotation
Fill Annotation

Map Styles

Map styles can be supplied by setting the styleString in the MapOptions. The following formats are supported:

  1. Passing the URL of the map style. This can be one of the built-in map styles, also see MapboxStyles or a custom map style served remotely using a URL that start with 'http(s)://' or 'mapbox://'
  2. Passing the style as a local asset. Create a JSON file in the assets and add a reference in pubspec.yml. Set the style string to the relative path for this asset in order to load it into the map.
  3. Passing the style as a local file. create an JSON file in app directory (e.g. ApplicationDocumentsDirectory). Set the style string to the absolute path of this JSON file.
  4. Passing the raw JSON of the map style. This is only supported on Android.

Offline Sideloading

Support for offline maps is available by side loading the required map tiles and including them in your assets folder.

  • Create your tiles package by following the guide available here.

  • Place the tiles.db file generated in step one in your assets directory and add a reference to it in your pubspec.yml file.

   assets:
     - assets/cache.db
  • Call installOfflineMapTiles when your application starts to copy your tiles into the location where Mapbox can access them. NOTE: This method should be called before the Map widget is loaded to prevent collisions when copying the files into place.
    try {
      await installOfflineMapTiles(join("assets", "cache.db"));
    } catch (err) {
      print(err);
    }

Downloading Offline Regions

An offline region is a defined region of a map that is available for use in conditions with limited or no network connection. Tiles for selected region, style and precision are downloaded from Mapbox using proper SDK methods and stored in application's cache.

  • Beware of selecting big regions, as size might be significant. Here is an online estimator https://docs.mapbox.com/playground/offline-estimator/.

  • Call downloadOfflineRegionStream with predefined OfflineRegion and optionally track progress in the callback function.

    final Function(DownloadRegionStatus event) onEvent = (DownloadRegionStatus status) {
      if (status.runtimeType == Success) {
        // ...
      } else if (status.runtimeType == InProgress) {
        int progress = (status as InProgress).progress.round();
        // ...
      } else if (status.runtimeType == Error) {
        // ...
      }
    };

    final OfflineRegion offlineRegion = OfflineRegion(
      bounds: LatLngBounds(
        northeast: LatLng(52.5050648, 13.3915634),
        southwest: LatLng(52.4943073, 13.4055383),
      ),
      id: 1,
      minZoom: 6,
      maxZoom: 18,
      mapStyleUrl: 'mapbox://styles/mapbox/streets-v11',
    );

    downloadOfflineRegionStream(offlineRegion, onEvent);

Location features

Android

Add the ACCESS_COARSE_LOCATION or ACCESS_FINE_LOCATION permission in the application manifest android/app/src/main/AndroidManifest.xml to enable location features in an Android application:

<manifest ...
    <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
    <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />

Starting from Android API level 23 you also need to request it at runtime. This plugin does not handle this for you. The example app uses the flutter 'location' plugin for this.

iOS

To enable location features in an iOS application:

If you access your users' location, you should also add the following key to ios/Runner/Info.plist to explain why you need access to their location data:

xml ...
    <key>NSLocationWhenInUseUsageDescription</key>
    <string>[Your explanation here]</string>

Recommended explanation about "Shows your location on the map and helps improve the map".

Contributing

We welcome contributions to this repository! If you're interested in helping build this Mapbox-Flutter integration, please read the contribution guide to learn how to get started.