All docsMapbox GL JSExamplesHighlight features within a bounding box

Highlight features within a bounding box

Hold Shift and drag the map to query features using queryRenderedFeatures.

Use a custom tileset

This example uses U.S. county data uploaded to Mapbox as a vector tileset. This data is not updated or maintained and should not be used in production applications.

If you're interested in creating an application that uses U.S. county data, you can download a Shapefile from census.gov's data portal and upload it to Mapbox Studio's Tilesets page.

<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>Highlight features within a bounding box</title>
<meta name="viewport" content="initial-scale=1,maximum-scale=1,user-scalable=no">
<link href="https://api.mapbox.com/mapbox-gl-js/v2.2.0/mapbox-gl.css" rel="stylesheet">
<script src="https://api.mapbox.com/mapbox-gl-js/v2.2.0/mapbox-gl.js"></script>
<style>
body { margin: 0; padding: 0; }
#map { position: absolute; top: 0; bottom: 0; width: 100%; }
</style>
</head>
<body>
<style>
.boxdraw {
background: rgba(56, 135, 190, 0.1);
border: 2px solid #3887be;
position: absolute;
top: 0;
left: 0;
width: 0;
height: 0;
}
</style>
<div id="map"></div>
<script>
// TO MAKE THE MAP APPEAR YOU MUST
// ADD YOUR ACCESS TOKEN FROM
// https://account.mapbox.com
mapboxgl.accessToken = '<your access token here>';
var map = new mapboxgl.Map({
container: 'map',
style: 'mapbox://styles/mapbox/streets-v11',
center: [-98, 38.88],
minZoom: 2,
zoom: 3
});
// Disable default box zooming.
map.boxZoom.disable();
// Create a popup, but don't add it to the map yet.
var popup = new mapboxgl.Popup({
closeButton: false
});
map.on('load', function () {
var canvas = map.getCanvasContainer();
// Variable to hold the starting xy coordinates
// when `mousedown` occured.
var start;
// Variable to hold the current xy coordinates
// when `mousemove` or `mouseup` occurs.
var current;
// Variable for the draw box element.
var box;
// Add a custom vector tileset source. The tileset used in
// this example contains a feature for every county in the U.S.
// Each county contains four properties. For example:
// {
// COUNTY: "Uintah County",
// FIPS: 49047,
// median-income: 62363,
// population: 34576
// }
map.addSource('counties', {
'type': 'vector',
'url': 'mapbox://mapbox.82pkq93d'
});
map.addLayer(
{
'id': 'counties',
'type': 'fill',
'source': 'counties',
'source-layer': 'original',
'paint': {
'fill-outline-color': 'rgba(0,0,0,0.1)',
'fill-color': 'rgba(0,0,0,0.1)'
}
},
'settlement-label'
); // Place polygon under these labels.
map.addLayer(
{
'id': 'counties-highlighted',
'type': 'fill',
'source': 'counties',
'source-layer': 'original',
'paint': {
'fill-outline-color': '#484896',
'fill-color': '#6e599f',
'fill-opacity': 0.75
},
'filter': ['in', 'FIPS', '']
},
'settlement-label'
); // Place polygon under these labels.
// Set `true` to dispatch the event before other functions
// call it. This is necessary for disabling the default map
// dragging behaviour.
canvas.addEventListener('mousedown', mouseDown, true);
// Return the xy coordinates of the mouse position
function mousePos(e) {
var rect = canvas.getBoundingClientRect();
return new mapboxgl.Point(
e.clientX - rect.left - canvas.clientLeft,
e.clientY - rect.top - canvas.clientTop
);
}
function mouseDown(e) {
// Continue the rest of the function if the shiftkey is pressed.
if (!(e.shiftKey && e.button === 0)) return;
// Disable default drag zooming when the shift key is held down.
map.dragPan.disable();
// Call functions for the following events
document.addEventListener('mousemove', onMouseMove);
document.addEventListener('mouseup', onMouseUp);
document.addEventListener('keydown', onKeyDown);
// Capture the first xy coordinates
start = mousePos(e);
}
function onMouseMove(e) {
// Capture the ongoing xy coordinates
current = mousePos(e);
// Append the box element if it doesnt exist
if (!box) {
box = document.createElement('div');
box.classList.add('boxdraw');
canvas.appendChild(box);
}
var minX = Math.min(start.x, current.x),
maxX = Math.max(start.x, current.x),
minY = Math.min(start.y, current.y),
maxY = Math.max(start.y, current.y);
// Adjust width and xy position of the box element ongoing
var pos = 'translate(' + minX + 'px,' + minY + 'px)';
box.style.transform = pos;
box.style.WebkitTransform = pos;
box.style.width = maxX - minX + 'px';
box.style.height = maxY - minY + 'px';
}
function onMouseUp(e) {
// Capture xy coordinates
finish([start, mousePos(e)]);
}
function onKeyDown(e) {
// If the ESC key is pressed
if (e.keyCode === 27) finish();
}
function finish(bbox) {
// Remove these events now that finish has been called.
document.removeEventListener('mousemove', onMouseMove);
document.removeEventListener('keydown', onKeyDown);
document.removeEventListener('mouseup', onMouseUp);
if (box) {
box.parentNode.removeChild(box);
box = null;
}
// If bbox exists. use this value as the argument for `queryRenderedFeatures`
if (bbox) {
var features = map.queryRenderedFeatures(bbox, {
layers: ['counties']
});
if (features.length >= 1000) {
return window.alert('Select a smaller number of features');
}
// Run through the selected features and set a filter
// to match features with unique FIPS codes to activate
// the `counties-highlighted` layer.
var filter = features.reduce(
function (memo, feature) {
memo.push(feature.properties.FIPS);
return memo;
},
['in', 'FIPS']
);
map.setFilter('counties-highlighted', filter);
}
map.dragPan.enable();
}
map.on('mousemove', function (e) {
var features = map.queryRenderedFeatures(e.point, {
layers: ['counties-highlighted']
});
// Change the cursor style as a UI indicator.
map.getCanvas().style.cursor = features.length ? 'pointer' : '';
if (!features.length) {
popup.remove();
return;
}
var feature = features[0];
popup
.setLngLat(e.lngLat)
.setText(feature.properties.COUNTY)
.addTo(map);
});
});
</script>
</body>
</html>