Supplement forward geocoding search results with another data source
This example adds a geocoding control on top of a web map and supplements the place data available through the Mapbox Geocoding API with custom data from a local data source.
Custom data is loaded into the example using the customData GeoJSON object. The forwardGeocoder function takes a user's query string and performs local geocoding to supplement Mapbox Geocoding API results with results from customData, adding a tree emoji (🌲) as a prefix for custom data results. Finally, it uses .addControl to add the mapbox-gl-geocoder plugin to the map, with the localGeocoder option defined as the forwardGeocoder function.
Search for Lincoln Park to see a custom feature appear as a search result.
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>Supplement forward geocoding search results with another data source</title>
<meta name="viewport" content="initial-scale=1,maximum-scale=1,user-scalable=no">
<link href="https://api.mapbox.com/mapbox-gl-js/v3.9.0/mapbox-gl.css" rel="stylesheet">
<script src="https://api.mapbox.com/mapbox-gl-js/v3.9.0/mapbox-gl.js"></script>
<style>
body { margin: 0; padding: 0; }
#map { position: absolute; top: 0; bottom: 0; width: 100%; }
</style>
</head>
<body>
<script src="https://api.mapbox.com/mapbox-gl-js/plugins/mapbox-gl-geocoder/v5.0.3/mapbox-gl-geocoder.min.js"></script>
<link rel="stylesheet" href="https://api.mapbox.com/mapbox-gl-js/plugins/mapbox-gl-geocoder/v5.0.3/mapbox-gl-geocoder.css" type="text/css">
<div id="map"></div>
<script>
// TO MAKE THE MAP APPEAR YOU MUST
// ADD YOUR ACCESS TOKEN FROM
// https://account.mapbox.com
mapboxgl.accessToken = 'YOUR_MAPBOX_ACCESS_TOKEN';
const map = new mapboxgl.Map({
container: 'map',
// Choose from Mapbox's core styles, or make your own style with Mapbox Studio
style: 'mapbox://styles/mapbox/dark-v11',
center: [-87.6244, 41.8756],
zoom: 13
});
// Load custom data to supplement the search results.
const customData = {
'features': [
{
'type': 'Feature',
'properties': {
'title': 'Lincoln Park is special'
},
'geometry': {
'coordinates': [-87.637596, 41.940403],
'type': 'Point'
}
},
{
'type': 'Feature',
'properties': {
'title': 'Burnham Park is special'
},
'geometry': {
'coordinates': [-87.603735, 41.829985],
'type': 'Point'
}
},
{
'type': 'Feature',
'properties': {
'title': 'Millennium Park is special'
},
'geometry': {
'coordinates': [-87.622554, 41.882534],
'type': 'Point'
}
}
],
'type': 'FeatureCollection'
};
function forwardGeocoder(query) {
const matchingFeatures = [];
for (const feature of customData.features) {
// Handle queries with different capitalization
// than the source data by calling toLowerCase().
if (
feature.properties.title
.toLowerCase()
.includes(query.toLowerCase())
) {
// Add a tree emoji as a prefix for custom
// data results using carmen geojson format:
// https://github.com/mapbox/carmen/blob/master/carmen-geojson.md
feature['place_name'] = `🌲 ${feature.properties.title}`;
feature['center'] = feature.geometry.coordinates;
feature['place_type'] = ['park'];
matchingFeatures.push(feature);
}
}
return matchingFeatures;
}
// Add the control to the map.
map.addControl(
new MapboxGeocoder({
accessToken: mapboxgl.accessToken,
localGeocoder: forwardGeocoder,
zoom: 14,
placeholder: 'Enter search e.g. Lincoln Park',
mapboxgl: mapboxgl
})
);
</script>
</body>
</html>
This code snippet will not work as expected until you replace
YOUR_MAPBOX_ACCESS_TOKEN with an access token from your Mapbox account.import React, { useEffect, useRef } from 'react';
import mapboxgl from 'mapbox-gl';
import MapboxGeocoder from '@mapbox/mapbox-gl-geocoder'
import 'mapbox-gl/dist/mapbox-gl.css';
import '@mapbox/mapbox-gl-geocoder/dist/mapbox-gl-geocoder.css'
const MapboxExample = () => {
const mapContainerRef = useRef();
const mapRef = useRef();
useEffect(() => {
// TO MAKE THE MAP APPEAR YOU MUST
// ADD YOUR ACCESS TOKEN FROM
// https://account.mapbox.com
mapboxgl.accessToken = 'YOUR_MAPBOX_ACCESS_TOKEN';
mapRef.current = new mapboxgl.Map({
container: mapContainerRef.current,
style: 'mapbox://styles/mapbox/dark-v11',
center: [-87.6244, 41.8756],
zoom: 13
});
const customData = {
'features': [
{
'type': 'Feature',
'properties': {
'title': 'Lincoln Park is special'
},
'geometry': {
'coordinates': [-87.637596, 41.940403],
'type': 'Point'
}
},
{
'type': 'Feature',
'properties': {
'title': 'Burnham Park is special'
},
'geometry': {
'coordinates': [-87.603735, 41.829985],
'type': 'Point'
}
},
{
'type': 'Feature',
'properties': {
'title': 'Millennium Park is special'
},
'geometry': {
'coordinates': [-87.622554, 41.882534],
'type': 'Point'
}
}
],
'type': 'FeatureCollection'
};
function forwardGeocoder(query) {
const matchingFeatures = [];
for (const feature of customData.features) {
if (feature.properties.title.toLowerCase().includes(query.toLowerCase())) {
feature['place_name'] = `🌲 ${feature.properties.title}`;
feature['center'] = feature.geometry.coordinates;
feature['place_type'] = ['park'];
matchingFeatures.push(feature);
}
}
return matchingFeatures;
}
mapRef.current.addControl(
new MapboxGeocoder({
accessToken: mapboxgl.accessToken,
localGeocoder: forwardGeocoder,
zoom: 14,
placeholder: 'Enter search e.g. Lincoln Park',
mapboxgl: mapboxgl
})
);
return () => mapRef.current.remove();
}, []);
return <div id="map" ref={mapContainerRef} style={{ height: '100%' }} />;
};
export default MapboxExample;
This code snippet will not work as expected until you replace
YOUR_MAPBOX_ACCESS_TOKEN with an access token from your Mapbox account.Was this example helpful?