flutter_map 0.12.0

A Dart implementation of Leaflet for Flutter apps

flutter_map

A Dart implementation of Leaflet for Flutter apps.

Installation

Add flutter_map to your pubspec:

dependencies:
  flutter_map: any # or the latest version on Pub

Android

Ensure the following permission is present in your Android Manifest file, located in <project root>/android/app/src/main/AndroidManifest.xml:

<uses-permission android:name="android.permission.INTERNET"/>

Usage

Configure the map using MapOptions and layer options:

Widget build(BuildContext context) {
  return FlutterMap(
    options: MapOptions(
      center: LatLng(51.5, -0.09),
      zoom: 13.0,
    ),
    layers: [
      TileLayerOptions(
        urlTemplate: "https://{s}.tile.openstreetmap.org/{z}/{x}/{y}.png",
        subdomains: ['a', 'b', 'c']
      ),
      MarkerLayerOptions(
        markers: [
          Marker(
            width: 80.0,
            height: 80.0,
            point: LatLng(51.5, -0.09),
            builder: (ctx) =>
            Container(
              child: FlutterLogo(),
            ),
          ),
        ],
      ),
    ],
  );
}

Alternatively initialize the map by specifying bounds instead of center and zoom.

MapOptions(
  bounds: LatLngBounds(LatLng(58.8, 6.1), LatLng(59, 6.2)),
  boundsOptions: FitBoundsOptions(padding: EdgeInsets.all(8.0)),
),

Azure Maps provider

Configure the map to use Azure Maps by using the following MapOptions and layer options:

Widget build(BuildContext context) {
  return new FlutterMap(
    options: new MapOptions(
      center: new LatLng(51.5, -0.09),
      zoom: 13.0,
    ),
    layers: [
      new TileLayerOptions(
        urlTemplate: "https://atlas.microsoft.com/map/tile/png?api-version=1&layer=basic&style=main&tileSize=256&view=Auto&zoom={z}&x={x}&y={y}&subscription-key={subscriptionKey}",
        additionalOptions: {
          'subscriptionKey': '<YOUR_AZURE_MAPS_SUBSCRIPTON_KEY>'
        },
      ),
      new MarkerLayerOptions(
        markers: [
          new Marker(
            width: 80.0,
            height: 80.0,
            point: new LatLng(51.5, -0.09),
            builder: (ctx) =>
            new Container(
              child: new FlutterLogo(),
            ),
          ),
        ],
      ),
    ],
  );
}

To use Azure Maps you will need to setup an account and get a subscription key

Open Street Map provider

Configure the map to use Open Street Map by using the following MapOptions and layer options:

Widget build(BuildContext context) {
  return new FlutterMap(
    options: new MapOptions(
      center: new LatLng(51.5, -0.09),
      zoom: 13.0,
    ),
    layers: [
      new TileLayerOptions(
        urlTemplate: "https://{s}.tile.openstreetmap.org/{z}/{x}/{y}.png",
        subdomains: ['a', 'b', 'c']
      ),
      new MarkerLayerOptions(
        markers: [
          new Marker(
            width: 80.0,
            height: 80.0,
            point: new LatLng(51.5, -0.09),
            builder: (ctx) =>
            new Container(
              child: new FlutterLogo(),
            ),
          ),
        ],
      ),
    ],
  );
}

Widget Layers

Use the new way to create layers (compatible with previous version)

Widget build(BuildContext context) {
  return FlutterMap(
    options: MapOptions(
      center: LatLng(51.5, -0.09),
      zoom: 13.0,
    ),
    layers: [
      MarkerLayerOptions(
        markers: [
          Marker(
            width: 80.0,
            height: 80.0,
            point: LatLng(51.5, -0.09),
            builder: (ctx) =>
            Container(
              child: FlutterLogo(),
            ),
          ),
        ],
      ),
    ],
    children: <Widget>[
      TileLayerWidget(options: TileLayerOptions(
        urlTemplate: "https://{s}.tile.openstreetmap.org/{z}/{x}/{y}.png",
        subdomains: ['a', 'b', 'c']
      )),
      MarkerLayerWidget(options: MarkerLayerOptions(
        markers: [
          Marker(
            width: 80.0,
            height: 80.0,
            point: LatLng(51.5, -0.09),
            builder: (ctx) =>
            Container(
              child: FlutterLogo(),
            ),
          ),
        ],
      )),
    ],
  );
}

Custom CRS

By default flutter_map supports only WGS84 (EPSG:4326) and Google Mercator (EPSG:3857) projections. With the integration of proj4dart any coordinate reference systems (CRS) can be defined and used.

Define custom CRS:

var resolutions = <double>[32768, 16384, 8192, 4096, 2048, 1024, 512, 256, 128];
var maxZoom = (resolutions.length - 1).toDouble();

var epsg3413CRS = Proj4Crs.fromFactory(
  code: 'EPSG:3413',
  proj4Projection:
      proj4.Projection.add('EPSG:3413', '+proj=stere +lat_0=90 +lat_ts=70 +lon_0=-45 +k=1 +x_0=0 +y_0=0 +datum=WGS84 +units=m +no_defs'),
  resolutions: resolutions,
);

Use Custom CRS in map and in WMS layers:

child: FlutterMap(
  options: MapOptions(
    // Set the map's CRS
    crs: epsg3413CRS,
    center: LatLng(65.05166470332148, -19.171744826394896),
    maxZoom: maxZoom,
  ),
  layers: [
    TileLayerOptions(
      wmsOptions: WMSTileLayerOptions(
        // Set the WMS layer's CRS too
        crs: epsg3413CRS,
        baseUrl: 'https://www.gebco.net/data_and_products/gebco_web_services/north_polar_view_wms/mapserv?',
        layers: ['gebco_north_polar_view'],
      ),
    ),
  ],
);

For more details visit Custom CRS demo page.

How to Cache Tiles (Custom TileProvider)

1. Using Flutter's NetworkImage: Flutter has a built in ImageProvider (NetworkImage) that caches images in memory until an app restart.

class CachedTileProvider extends TileProvider {
  const CachedTileProvider();
  @override
  ImageProvider getImage(Coords<num> coords, TileLayerOptions options) {
    return NetworkImage(getTileUrl(coords, options));
  }
}

2. Using the cached_network_image dependency: This dependency has an ImageProvider that caches to disk which means the cache persists through an app restart.

import 'package:cached_network_image/cached_network_image.dart';

class CachedTileProvider extends TileProvider {
  const CachedTileProvider();
  @override
  ImageProvider getImage(Coords<num> coords, TileLayerOptions options) {
    return CachedNetworkImageProvider(
      getTileUrl(coords, options),
      //Now you can set options that determine how the image gets cached via whichever plugin you use.
    );
  }
}

Lastly we need to add the CachedTileProvider TileProvider to TileLayerOptions

TileLayerOptions(
  urlTemplate: 'https://example.com/{x}/{y}/{z}',
  tileProvider: const CachedTileProvider()
)

Run the example

See the example/ folder for a working example app.

To run it, in a terminal cd into the folder. Then execute ulimit -S -n 2048 (ref). Then execute flutter run with a running emulator.

Offline maps

Follow this guide to grab offline tiles
Once you have your map exported to .mbtiles, you can use mbtilesToPng to unpack into /{z}/{x}/{y}.png. Move this to Assets folder and add asset directories to pubspec.yaml. Minimum required fields for offline maps are:

Widget build(ctx) {
  return FlutterMap(
    options: MapOptions(
      center: LatLng(56.704173, 11.543808),
      zoom: 13.0,
      swPanBoundary: LatLng(56.6877, 11.5089),
      nePanBoundary: LatLng(56.7378, 11.6644),
    ),
    layers: [
      TileLayerOptions(
        tileProvider: AssetTileProvider(),
        urlTemplate: "assets/offlineMap/{z}/{x}/{y}.png",
      ),
    ],
  );
}

Make sure PanBoundaries are within offline map boundary to stop missing asset errors.
See the flutter_map_example/ folder for a working example.

Note that there is also FileTileProvider(), which you can use to load tiles from the filesystem.

Plugins

• flutter_map_marker_cluster: Provides Beautiful Animated Marker Clustering functionality
• user_location: A plugin to handle and plot the current user location in FlutterMap
• flutter_map_location: A plugin to request and display the users location and heading on the map
• flutter_map_location_marker: A simple and powerful plugin display the users location and heading
• flutter_map_tappable_polyline: A plugin to add onTap callback to Polyline
• lat_lon_grid_plugin: Adds a latitude / longitude grid as plugin to the FlutterMap
• flutter_map_marker_popup: A plugin to show customisable popups for markers.
• map_elevation: A widget to display elevation of a track (polyline) like Leaflet.Elevation

Roadmap

For the latest roadmap, please see the Issue Tracker