# Flutter Mapbox GL > **Please note that this project is community driven and is not an official Mapbox product.** > > We welcome [feedback](https://github.com/tobrun/flutter-mapbox-gl/issues) and contributions. ## Table of contents - [Flutter Mapbox GL](#flutter-mapbox-gl) - [Table of contents](#table-of-contents) - [Introduction](#introduction) - [Setting up](#setting-up) - [Mobile](#mobile) - [Secret Mapbox access token](#secret-mapbox-access-token) - [Web](#web) - [All platforms](#all-platforms) - [Public Mapbox access token](#public-mapbox-access-token) - [Supported API](#supported-api) - [Map Styles](#map-styles) - [Offline Sideloading](#offline-sideloading) - [Downloading Offline Regions](#downloading-offline-regions) - [Create a static map snapshot](#create-a-static-map-snapshot) - [Location features](#location-features) - [Android](#android) - [iOS](#ios) - [Running the example code](#running-the-example-code) - [Contributing](#contributing) ## Introduction 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](https://github.com/mapbox/mapbox-gl-native). For web, we rely on [mapbox-gl-js](https://github.com/mapbox/mapbox-gl-js). This project only supports a subset of the API exposed by these libraries. ![screenshot.png](screenshot.png) ## Setting up This package is available on [pub.dev](https://pub.dev/packages/mapbox_gl). Get it by running the following command: ``` flutter pub add mapbox_gl ``` ### Mobile #### Secret Mapbox access token A secret access token with the `Downloads: Read` scope is required for the underlying Mapbox SDKs to be downloaded. Information on setting it up is available in the Mapbox documentation: [Android](https://docs.mapbox.com/android/maps/guides/install/), [iOS](https://docs.mapbox.com/ios/maps/guides/install/). If the properly configured token is not present, the build process fails with one the following errors *(for Android/iOS respectively)*: ``` * What went wrong: A problem occurred evaluating project ':mapbox_gl'. > SDK Registry token is null. See README.md for more information. ``` ``` [!] Error installing Mapbox-iOS-SDK curl: (22) The requested URL returned error: 401 Unauthorized ``` ### Web Include the JavaScript and CSS files in the `` of your `index.html` file: ``` ``` *Note: Look for latest version in [Mapbox GL JS documentation](https://docs.mapbox.com/mapbox-gl-js/guides/).* ### All platforms #### Public Mapbox access token A public access token must be provided to a MapboxMap widget for retrieving styles and resources. While you can hardcode it directly into source files, it's good practise to retrieve access tokens from some external source (e.g. a config file or an environment variable). The example app uses the following technique: The access token is passed via the command line arguments when either building ``` flutter build --dart-define ACCESS_TOKEN=YOUR_TOKEN_HERE ``` or running the application ``` flutter run --dart-define ACCESS_TOKEN=YOUR_TOKEN_HERE ``` Then it's retrieved in Dart: ``` MapboxMap( ... accessToken: const String.fromEnvironment("ACCESS_TOKEN"), ... ) ``` ## Supported API | Feature | Android | iOS | Web | | ------ | ------ | ----- | ----- | | Style | :white_check_mark: | :white_check_mark: | :white_check_mark: | | Camera | :white_check_mark: | :white_check_mark: | :white_check_mark: | | Gesture | :white_check_mark: | :white_check_mark: | :white_check_mark: | | User Location | :white_check_mark: | :white_check_mark: | :white_check_mark: | | Style DSL | :x: | :x: | :x: | | Raster Layer | :white_check_mark: | :white_check_mark: | :white_check_mark: | | Symbol Layer | :white_check_mark: | :white_check_mark: | :white_check_mark: | | Circle Layer | :white_check_mark: | :white_check_mark: | :white_check_mark: | | Line Layer | :white_check_mark: | :white_check_mark: | :white_check_mark: | | Fill Layer | :white_check_mark: | :white_check_mark: | :white_check_mark: | | Fill Extrusion Layer | :white_check_mark: | :white_check_mark: | :white_check_mark: | | Hillshade Layer | :white_check_mark: | :white_check_mark: | :white_check_mark: | | Heatmap Layer | :white_check_mark: | :white_check_mark: | :white_check_mark: | | Vector Source | :white_check_mark: | :white_check_mark: | :white_check_mark: | | Raster Source | :white_check_mark: | :white_check_mark: | :white_check_mark: | | GeoJson Source | :white_check_mark: | :white_check_mark: | :white_check_mark: | | Image Source | :white_check_mark: | :white_check_mark: | :white_check_mark: | | Expressions | :white_check_mark: | :white_check_mark: | :white_check_mark: | | Symbol Annotation | :white_check_mark: | :white_check_mark: | :white_check_mark: | | Circle Annotation | :white_check_mark: | :white_check_mark: | :white_check_mark: | | Line Annotation | :white_check_mark: | :white_check_mark: | :white_check_mark: | | Fill Annotation | :white_check_mark: | :white_check_mark: | :white_check_mark: | ## 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](https://docs.mapbox.com/ios/maps/overview/offline/). * 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); ``` ## Create a static map snapshot The snapshotManager generates static raster images of the map. Each snapshot image depicts a portion of a map defined by an SnapshotOptions object you provide. * Call `takeSnapshot` with predefined `SnapshotOptions` ``` final renderBox = mapKey.currentContext?.findRenderObject() as RenderBox; final snapshotOptions = SnapshotOptions( width: renderBox.size.width, height: renderBox.size.height, writeToDisk: true, withLogo: false, ); final uri = await mapController?.takeSnapshot(snapshotOptions); ``` ## 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: ```

``` 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](https://pub.dev/packages/location) 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 ... NSLocationWhenInUseUsageDescription [Your explanation here] ``` [Recommended](https://docs.mapbox.com/help/tutorials/first-steps-ios-sdk/#display-the-users-location) explanation about "Shows your location on the map and helps improve the map". ## Flutter 3.x.x issues and experimental workarounds Since Flutter 3.x.x was introduced, it exposed some race conditions resulting in occasional crashes upon map disposal. The parameter `useDelayedDisposal` was introduced as a workaround for this issue until Flutter and/or Mapbox fix this issue properly. Use with caution - this is not yet production ready since several users still report crashes after using this workaround. ## Running the example code See the [documentation about this topic](doc/RUNNING_EXAMPLE_CODE.md) ## Contributing We welcome contributions to this repository! If you're interested in helping build this Mapbox-Flutter integration, please read [the contribution guide](https://github.com/tobrun/flutter-mapbox-gl/blob/master/CONTRIBUTING.md) to learn how to get started.

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