Can we fill color for countries in google_maps_flutter?
2,430
Solution 1
After spending 4 days in looking into map stuff and it's features I got most easy and feasible solution for filling any country, state, continent in flutter. We can get the geoJson data of any region from here
Extract the latLong co-ordinates of that region and draw a polygon based on it.
Following is the code for filling India with colour.
GeoJson.dart
class GeoJson
{
static const List IN = [
[77.83745079947457,35.494009507787766],[78.91226891471322,34.32193634697579],
[78.81108646028574,33.50619802503242],[79.20889163606857,32.994394639613716],
[79.17612877799553,32.48377981213771],[78.45844648632601,32.61816437431273],
[78.73889448437401,31.515906073527063],[79.7213668151071,30.882714748654728],
[81.11125613802932,30.183480943313402],[80.4767212259174,29.72986522065534],
[80.08842451367627,28.79447011974014],[81.05720258985203,28.416095282499043],
[81.99998742058497,27.925479234319994],[83.30424889519955,27.36450572357556],
[84.6750179381738,27.234901231387536],[85.25177859898338,26.72619843190634],
[86.02439293817918,26.63098460540857],[87.22747195836628,26.397898057556077],
[88.06023766474982,26.41461538340249],[88.17480431514092,26.81040517832595],
[88.04313276566123,27.445818589786825],[88.12044070836987,27.876541652939594],
[88.73032596227856,28.086864732367516],[88.81424848832054,27.29931590423936],
[88.83564253128938,27.098966376243762],[89.74452762243884,26.719402981059957],
[90.37327477413407,26.87572418874288],[91.21751264848643,26.808648179628022],
[92.03348351437509,26.83831045176356],[92.10371178585973,27.452614040633208],
[91.69665652869668,27.77174184825166],[92.50311893104364,27.89687632904645],
[93.41334760943268,28.640629380807226],[94.56599043170294,29.277438055939985],
[95.40480228066464,29.03171662039213],[96.11767866413103,29.452802028922466],
[96.58659061074749,28.830979519154344],[96.24883344928779,28.41103099213444],
[97.32711388549004,28.26158274994634],[97.40256147663612,27.88253611908544],
[97.0519885599681,27.69905894623315],[97.1339990580153,27.083773505149964],
[96.41936567585097,27.264589341739224],[95.12476769407496,26.5735720891323],
[95.1551534362626,26.001307277932085],[94.60324913938538,25.162495428970402],
[94.55265791217164,24.675238348890332],[94.10674197792505,23.85074087167348],
[93.3251876159428,24.078556423432204],[93.28632693885928,23.043658352139005],
[93.06029422401463,22.70311066333557],[93.16612755734836,22.278459580977103],
[92.67272098182556,22.041238918541254],[92.14603478390681,23.627498684172593],
[91.86992760617132,23.624346421802784],[91.70647505083211,22.985263983649183],
[91.15896325069971,23.50352692310439],[91.46772993364367,24.072639471934792],
[91.91509280799443,24.13041372323711],[92.37620161333481,24.976692816664965],
[91.79959598182207,25.147431748957317],[90.8722107279121,25.132600612889547],
[89.92069258012185,25.26974986419218],[89.83248091019962,25.96508209889548],
[89.35509402868729,26.014407253518073],[88.56304935094977,26.44652558034272],
[88.2097892598025,25.76806570078271],[88.93155398962308,25.238692328384776],
[88.30637251175602,24.866079413344206],[88.08442223506242,24.501657212821925],
[88.69994022009092,24.23371491138856],[88.52976972855377,23.631141872649163],
[88.87631188350309,22.879146429937826],[89.03196129756623,22.055708319582976],
[88.88876590368542,21.690588487224748],[88.20849734899521,21.703171698487807],
[86.97570438024027,21.49556163175521],[87.03316857294887,20.743307806882413],
[86.49935102737378,20.151638495356607],[85.0602657409097,19.4785788029711],
[83.94100589390001,18.302009792549725],[83.18921715691785,17.67122142177898],
[82.19279218946592,17.016636053937813],[82.19124189649719,16.556664130107848],
[81.69271935417748,16.310219224507904],[80.79199913933014,15.951972357644491],
[80.32489586784388,15.899184882058348],[80.02506920768644,15.136414903214147],
[80.2332735533904,13.835770778859981],[80.28629357292186,13.006260687710833],
[79.8625468281285,12.056215318240888],[79.85799930208682,10.35727509199711],
[79.340511509116,10.30885427493962],[78.88534549348918,9.546135972527722],
[79.18971967968828,9.216543687370148],[78.2779407083305,8.933046779816934],
[77.94116539908435,8.252959092639742],[77.53989790233794,7.965534776232333],
[76.59297895702167,8.89927623131419],[76.13006147655108,10.299630031775521],
[75.74646731964849,11.308250637248307],[75.39610110870957,11.781245022015824],
[74.86481570831681,12.741935736537897],[74.61671715688354,13.99258291264968],
[74.44385949086723,14.617221787977696],[73.5341992532334,15.99065216721496],
[73.11990929554943,17.928570054592498],[72.82090945830865,19.208233547436166],
[72.8244751321368,20.419503282141534],[72.6305334817454,21.356009426351008],
[71.17527347197395,20.757441311114235],[70.4704586119451,20.877330634031384],
[69.16413008003883,22.0892980005727],[69.64492760608239,22.450774644454338],
[69.34959679553435,22.84317963306269],[68.1766451353734,23.69196503345671],
[68.84259931831878,24.35913361256094],[71.04324018746823,24.3565239527302],
[70.84469933460284,25.21510203704352],[70.28287316272558,25.72222870533983],
[70.16892662952202,26.491871649678842],[69.51439293811312,26.940965684511372],
[70.61649620960193,27.989196275335868],[71.77766564320032,27.913180243434525],
[72.8237516620847,28.961591701772054],[73.45063846221743,29.97641347911987],
[74.42138024282026,30.979814764931177],[74.40592898956501,31.69263947196528],
[75.25864179881322,32.2711054550405],[74.45155927927871,32.7648996038055],
[74.10429365427734,33.44147329358685],[73.74994835805195,34.31769887952785],
[74.24020267120497,34.74888703057125],[75.75706098826834,34.50492259372132],
[76.87172163280403,34.65354401299274],[77.83745079947457,35.494009507787766]];
}
main.dart
@override
void initState() {
addPoints();
List< Polygon > addPolygon = [
Polygon(
polygonId: PolygonId( 'India' ),
points: point,
consumeTapEvents: true,
strokeColor: Colors.grey,
strokeWidth: 1,
fillColor: Colors.redAccent,
),
];
polygon.addAll( addPolygon );
super.initState();
}
void addPoints()
{
for( var i=0 ; i < GeoJson.IN.length ; i++ )
{
var ltlng= LatLng( GeoJson.IN[ i ][ 1 ], GeoJson.IN[ i ][ 0 ] );
point.add( ltlng );
}
}
void _onMapCreated(GoogleMapController controller)
{
mapController = controller;
}
Widget mapState()
{
return GoogleMap(
onMapCreated: _onMapCreated,
initialCameraPosition: CameraPosition(
target: _center,
zoom: 0.0
),
scrollGesturesEnabled: true,
zoomGesturesEnabled: true,
myLocationButtonEnabled: false,
gestureRecognizers: Set()
..add( Factory<PanGestureRecognizer>(() => PanGestureRecognizer())),
//markers: markers,
polygons: polygon,
);
}
Solution 2
For anyone wondering - here is the full main.dart code that can be copy & pasted in order to work. Make sure to add your API key for google maps under android/app/src/main/AndroidManifest.xml.
Lastly add the geojson.dart as described above.
import 'package:flutter/foundation.dart';
import 'package:flutter/gestures.dart';
import 'package:flutter/material.dart';
import 'package:google_maps_flutter/google_maps_flutter.dart';
import 'geojson.dart';
void main() {
runApp(MyApp());
}
class MyApp extends StatelessWidget {
// This widget is the root of your application.
@override
Widget build(BuildContext context) {
return MaterialApp(
title: 'Flutter Demo',
theme: ThemeData(
// This is the theme of your application.
//
// Try running your application with "flutter run". You'll see the
// application has a blue toolbar. Then, without quitting the app, try
// changing the primarySwatch below to Colors.green and then invoke
// "hot reload" (press "r" in the console where you ran "flutter run",
// or simply save your changes to "hot reload" in a Flutter IDE).
// Notice that the counter didn't reset back to zero; the application
// is not restarted.
primarySwatch: Colors.blue,
// This makes the visual density adapt to the platform that you run
// the app on. For desktop platforms, the controls will be smaller and
// closer together (more dense) than on mobile platforms.
visualDensity: VisualDensity.adaptivePlatformDensity,
),
home: MyHomePage(title: 'Flutter Demo Home Page'),
);
}
}
class MyHomePage extends StatefulWidget {
MyHomePage({Key key, this.title}) : super(key: key);
final String title;
@override
_MyHomePageState createState() => _MyHomePageState();
}
class _MyHomePageState extends State {
Set polygon = new Set();
List point = [];
GoogleMapController mapController;
@override
void initState() {
addPoints();
List addPolygon = [
Polygon(
polygonId: PolygonId( 'India' ),
points: point,
consumeTapEvents: true,
strokeColor: Colors.grey,
strokeWidth: 1,
fillColor: Colors.redAccent,
),
];
polygon.addAll( addPolygon );
super.initState();
}
void addPoints()
{
for( var i=0 ; i (() => PanGestureRecognizer())),
//markers: markers,
polygons: polygon,
);
}
@override
Widget build(BuildContext context) {
// TODO: implement build
return mapState();
}
}
Author by
my bytecode
Updated on December 18, 2022Comments
-
my bytecode over 1 year
I'm implementing the google_maps_flutter plugin in my flutter app and stucked in highlighting the country for example India by red color, Australia by blue etc. I went throught geoJson but not sure how to implement it in flutter.
Thanks in advance.
-
Monis about 4 yearsperfect answer! -
my bytecode about 4 yearsThank you @Monis