Offline Map | Maps SDK for Flutter | Mapbox Docs

This example shows how to download map tiles for offline use. Specifically, it shows how to download Style Packs and Tile Regions using OfflineManager. For more guidance on using offline maps in your application read out our Offline Maps Guide.
dart
offline_map.dart
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import 'dart:async';

import 'package:flutter/cupertino.dart';
import 'package:flutter/material.dart';
import 'package:flutter/widgets.dart';
import 'package:mapbox_maps_flutter/mapbox_maps_flutter.dart';
import 'package:path_provider/path_provider.dart';

import 'page.dart';
import 'utils.dart';

class OfflineMapPage extends ExamplePage {
  OfflineMapPage() : super(const Icon(Icons.wifi_off), 'Offline Map');

  @override
  Widget build(BuildContext context) {
    return const OfflineMapWidget();
  }
}

class OfflineMapWidget extends StatefulWidget {
  const OfflineMapWidget();

  @override
  State createState() => OfflineMapWidgetState();
}

class OfflineMapWidgetState extends State<OfflineMapWidget> {
  MapboxMap? mapboxMap;
  final StreamController<double> _stylePackProgress =
      StreamController.broadcast();
  final StreamController<double> _tileRegionLoadProgress =
      StreamController.broadcast();

  _onMapCreated(MapboxMap mapboxMap) async {
    this.mapboxMap = mapboxMap;
    await _downloadStylePack();
    await _downloadTileRegion();
  }

  _downloadStylePack() async {
    final offlineManager = await OfflineManager.create();
    final stylePackLoadOptions = StylePackLoadOptions(
        glyphsRasterizationMode:
            GlyphsRasterizationMode.IDEOGRAPHS_RASTERIZED_LOCALLY,
        metadata: {"tag": "test"},
        acceptExpired: false);
    offlineManager.loadStylePack(MapboxStyles.OUTDOORS, stylePackLoadOptions,
        (progress) {
      final percentage =
          progress.completedResourceCount / progress.requiredResourceCount;
      if (!_stylePackProgress.isClosed) {
        _stylePackProgress.sink.add(percentage);
      }
    }).then((value) {
      _stylePackProgress.sink.add(1);
      _stylePackProgress.sink.close();
    });
  }

  _downloadTileRegion() async {
    final tmpDir = await getTemporaryDirectory();
    final tileStore = await TileStore.createAt(await tmpDir.uri);
    final tileRegionLoadOptions = TileRegionLoadOptions(
        geometry: Point(coordinates: Position(-80.1263, 25.7845)).toJson(),
        descriptorsOptions: [
          TilesetDescriptorOptions(
              styleURI: MapboxStyles.OUTDOORS, minZoom: 0, maxZoom: 16)
        ],
        acceptExpired: true,
        networkRestriction: NetworkRestriction.NONE);

    tileStore.loadTileRegion("my-tile-region", tileRegionLoadOptions,
        (progress) {
      final percentage =
          progress.completedResourceCount / progress.requiredResourceCount;
      if (!_tileRegionLoadProgress.isClosed) {
        _tileRegionLoadProgress.sink.add(percentage);
      }
    }).then((value) {
      _tileRegionLoadProgress.sink.add(1);
      _tileRegionLoadProgress.sink.close();
    });
  }

  @override
  Widget build(BuildContext context) {
    final mapWidget = MapWidget(
      key: ValueKey("mapWidget"),
      styleUri: MapboxStyles.OUTDOORS,
      cameraOptions: CameraOptions(center: City.helsinki, zoom: 2.0),
      onMapCreated: _onMapCreated,
    );

    return new Column(
      mainAxisSize: MainAxisSize.min,
      children: [
        Expanded(
          child: mapWidget,
        ),
        SizedBox(
            height: 100,
            child: Card(
              child: Column(
                mainAxisSize: MainAxisSize.min,
                children: [
                  StreamBuilder(
                      stream: _stylePackProgress.stream,
                      initialData: 0.0,
                      builder: (context, snapshot) {
                        return Column(
                          mainAxisSize: MainAxisSize.min,
                          children: [
                            Text("Style pack ${snapshot.requireData}"),
                            LinearProgressIndicator(
                              value: snapshot.requireData,
                            )
                          ],
                        );
                      }),
                  StreamBuilder(
                      stream: _tileRegionLoadProgress.stream,
                      initialData: 0.0,
                      builder: (context, snapshot) {
                        return Column(
                            mainAxisSize: MainAxisSize.min,
                            children: [
                              Text("Tile region ${snapshot.requireData}"),
                              LinearProgressIndicator(
                                value: snapshot.requireData,
                              )
                            ]);
                      }),
                ],
              ),
            ))
      ],
    );
  }
}
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