Adding popups on hovering to custom markers using Mapbox gl js

Question

I'm adopting this example but I need popups to appear on hover not on click. Here is how popups are added now:

new mapboxgl.Marker(el, {
  offset: [0, -25]
})
.setLngLat(marker.geometry.coordinates)
.setPopup(new mapboxgl.Popup()//add popups
    .setHTML('<h3>' + marker.properties.title + '</h3><p><a href="' + marker.properties.link + '" target="_blank">' + marker.properties.description + '</a></p><p><a href="' + marker.properties.link + '" target="_blank"><img src="' + marker.properties.picture + '" title="" /></a></p>'))
.addTo(map);

It is my jsFiddle, could anyone help me to fix that problem?

Answer 1

mapboxgl.Marker are implemented as simple HTML <div> elements. You can attach standard event listener to them and toggle the popup manually:

const marker = new mapboxgl.Marker({/* options */});
const markerDiv = marker.getElement();

markerDiv.addEventListener('mouseenter', () => marker.togglePopup());
markerDiv.addEventListener('mouseleave', () => marker.togglePopup());

See docs: https://docs.mapbox.com/mapbox-gl-js/api/#marker#getelement

EDIT: Preventing the popup from opening on click

I did some testing, and the only thing reliably working is to call marker.togglePopup() in your own click handler

map.on('click', event => {
  const target = event.originalEvent.target;
  const markerWasClicked = markerDiv.contains(target);

  marker.togglePopup();
});

Full example: https://jsfiddle.net/am2jwtzg/

Answer 2

Scarysize answer is working. However, if you click on the marker while you hover over it, the pop-up will be closed and on leaving the marker the pop-up will open again.

To prevent this behaviour you should use the methods marker.addTo(map) and marker.remove() These methods are used internally by the marker.togglePopup() function: Marker source

togglePopup() {
    var popup = this._popup;

    if (!popup) return;
    else if (popup.isOpen()) popup.remove();
    else popup.addTo(this._map);
}

working example below

mapboxgl.accessToken = 'pk.eyJ1IjoibW9ycGhvY29kZSIsImEiOiJVMnRPS0drIn0.QrB-bpBR5Tgnxa6nc9TqmQ';

var monument = [-77.0353, 38.8895];
var map = new mapboxgl.Map({
    container: 'map',
    style: 'mapbox://styles/mapbox/light-v9',
    center: monument,
    zoom: 15
});

// create the popup
var popup = new mapboxgl.Popup(
	{offset:[28, 0]}
).setText(
	'Construction on the Washington Monument began in 1848.'
);
// create the marker
let marker = new mapboxgl.Marker().setLngLat(monument);

// get the marker element
const element = marker.getElement();
element.id = 'marker'
// hover event listener
element.addEventListener('mouseenter', () => popup.addTo(map));
element.addEventListener('mouseleave', () => popup.remove());

// add popup to marker
marker.setPopup(popup);
// add marker to map
marker.addTo(map);

#map { position:absolute; top:0; bottom:0; width:100%; }
#marker {
    background-image: url('https://www.mapbox.com/mapbox-gl-js/assets/washington-monument.jpg');
    background-size: cover;
    width: 50px;
    height: 50px;
    border-radius: 50%;
    cursor: pointer;
}

.mapboxgl-popup {
    max-width: 200px;
}

<link href="https://api.tiles.mapbox.com/mapbox-gl-js/v0.28.0/mapbox-gl.css" rel="stylesheet"/>
<script src="https://api.tiles.mapbox.com/mapbox-gl-js/v0.28.0/mapbox-gl.js"></script>
<div id="map"></div>