[leaflet] Leaflet changing Marker color

Is there a way to randomly change marker-colors in native Leaflet? I'm using svg elements which could be styled. I know that it is possible with mapbox.js

EDIT: To clarify what I intend to do: If you add markers to the map via a doubleclick or something it should have random colors. To achieve this I wanted to use svg icons for the markers to style them.

This is my code:

    myIcon = L.icon({
      iconUrl: "icon_33997.svg",
      iconAnchor: pinAnchor
    });

    newMarker = L.marker(lat, long], {
      icon: myIcon
    });

Write a function which, given a color (or any other characteristics), returns an SVG representation of the desired icon. Then, when creating the marker, reference this function with the appropriate parameter(s).

In R, use the addAwesomeMarkers() function. Sample code producing red marker:

leaflet() %>%
addTiles() %>%
addAwesomeMarkers(lng = -77.03654, lat = 38.8973, icon = awesomeIcons(icon = 'ion-ionic', library = 'ion', markerColor = 'red'))

Link for ion icons: http://ionicons.com/

1) Add the marker 2) find the backgroundcolor attribute for the css and change it. Here it is:
JS

var myIcon = L.divIcon({
      className: 'my-div-icon',
      iconSize: [5, 5]
    });
var marker = L.marker([50,-20], {icon: myIcon}).addTo(map);
    marker.valueOf()._icon.style.backgroundColor = 'green'; //or any color

So this is one of the top hits in Google for styling Leaflet Icon, but it didn't have a solution that worked without third parties, and I was having this problem in React as we needed dynamic colours for our routes and icons.

The solution I came up with was to use Leaflet.DivIcon html attribute, it allows you to pass a string which is evaluated into a DOM element.

So for example I created a marker style follows:

const myCustomColour = '#583470'

const markerHtmlStyles = `
  background-color: ${myCustomColour};
  width: 3rem;
  height: 3rem;
  display: block;
  left: -1.5rem;
  top: -1.5rem;
  position: relative;
  border-radius: 3rem 3rem 0;
  transform: rotate(45deg);
  border: 1px solid #FFFFFF`

const icon = Leaflet.divIcon({
  className: "my-custom-pin",
  iconAnchor: [0, 24],
  labelAnchor: [-6, 0],
  popupAnchor: [0, -36],
  html: `<span style="${markerHtmlStyles}" />`
})

Change background-color in markerHtmlStyles to your custom colour and you're good to go.

I found the SVG marker/icon to be best one yet. It is very flexible and allows any color you like. You can customize the entire icon without much of a hassle:

function createIcon(markerColor) {
  /* ...Code ommitted ... */

  return new L.DivIcon.SVGIcon({
            color: markerColor,
            iconSize: [15,30],
            circleRatio: 0.35
  });
}

Ahh an event listener and change the icon through setIcon() method:

createdMarker.on("dblclick", function(evt) {

        var myIcon = L.icon({
            iconUrl: 'res/marker-icon-red.png',
            shadowUrl: 'res/marker-shadow.png'
        });
        this.setIcon(myIcon);
});

Bind in the icons from this site!

https://github.com/pointhi/leaflet-color-markers

Detailed how-to information included on the website.

Edit: Use the code below to add a marker icon and just replace the link to the one with the color of your choice. (i.e. marker-icon-2x-green.png to some other image)

var greenIcon = new L.Icon({
  iconUrl: 'https://raw.githubusercontent.com/pointhi/leaflet-color-markers/master/img/marker-icon-2x-green.png',
  shadowUrl: 'https://cdnjs.cloudflare.com/ajax/libs/leaflet/0.7.7/images/marker-shadow.png',
  iconSize: [25, 41],
  iconAnchor: [12, 41],
  popupAnchor: [1, -34],
  shadowSize: [41, 41]
});

L.marker([51.5, -0.09], {icon: greenIcon}).addTo(map);

Leaflet Markers are stored as files unlike other objects (like Polylines, etc.)

If you want your own markers, you can find The official Leaflet Tutorial that explains how to do it.

EDIT :

After reading this conversation with the main developer I searched for the marker SVG and here it is.

With this you should be able to color the marker the way you want and randomly set their color.

EDIT AGAIN :

You can use MakiMarkers to set the color of a marker and use this extension to make some random stuffs. (It's simple and well explained)

Html code for adding map

<div id="map" style="height:480px; width:360px;"></div>

css for loading map

.leaflet-div-icon
{
    background-image: url('http://cloudmade.com/images/layout/cm-logo.png');
}

Logic for changing marker colour

var map = L.map('map').setView([51.5, -0.09], 13);
        
L.marker([51.49, -0.09]).addTo(map)
    .bindPopup('Demo CSS3 popup. <br> Easily customizable.');
        
const myCustomColour = '#5f93ed'
        
const markerHtmlStyles = `
    background-color: ${myCustomColour};
    width: 15px;
    height: 15px;
    font-size:15px;
    text-align:center;
    display: block; 
`
        
function thing(ct) {
    return L.divIcon({
        className: "box",
        iconAnchor: [12, 25],
        labelAnchor: [-6, 0],
        popupAnchor: [0, -15],
        html: `<span style="${markerHtmlStyles}" >M</span>`
    })
}
       
L.marker([51.51, -0.09], {
    icon: thing("hello")
}).addTo(map)
    .bindPopup('divIcon CSS3 popup. <br> Supposed to be easily stylable.');

adding to @tutts excelent answer, I modified it to this:

... includes a caption - where you can use FontAwesome icons or alike ...

var myCustomColour = '#334455d0', // d0 -> alpha value
    lat = 5.5,
    lon = 5.5;

var caption = '', // '<i class="fa fa-eye" />' or 'abc' or ...
    size = 10,    // size of the marker
    border = 2;   // border thickness

var markerHtmlStyles = ' \
    background-color: ' + myCustomColour + '; \
    width: '+ (size * 3) +'px; \
    height: '+ (size * 3) +'px; \
    display: block; \
    left: '+ (size * -1.5) +'px; \
    top: '+ (size * -1.5) +'px; \
    position: relative; \
    border-radius: '+ (size * 3) +'px '+ (size * 3) +'px 0; \
    transform: rotate(45deg); \
    border: '+border+'px solid #FFFFFF;\
    ';

var captionStyles = '\
    transform: rotate(-45deg); \
    display:block; \
    width: '+ (size * 3) +'px; \
    text-align: center; \
    line-height: '+ (size * 3) +'px; \
    ';

var icon = L.divIcon({
    className: "color-pin-" + myCustomColour.replace('#', ''),

    // on another project this is needed: [0, size*2 + border/2]
    iconAnchor: [border, size*2 + border*2], 

    labelAnchor: [-(size/2), 0],
    popupAnchor: [0, -(size*3 + border)],
    html: '<span style="' + markerHtmlStyles + '"><span style="'+captionStyles+'">'+ caption + '</span></span>'
});

var marker = L.marker([lat, lon], {icon: icon})
.addTo(mymap);

and the ES6 version (like @tutts) .. I am using it with vue-leaflet

// caption could be: '<i class="fa fa-eye" />',_x000D_
function makeMarkerIcon(color, caption) {_x000D_
 let myCustomColour = color + 'd0';_x000D_
_x000D_
 let size = 10,    // size of the marker_x000D_
  border = 2;   // border thickness_x000D_
_x000D_
 let markerHtmlStyles = `_x000D_
  background-color: ${myCustomColour};_x000D_
  width: ${size * 3}px;_x000D_
  height: ${size * 3}px;_x000D_
  display: block;_x000D_
  left: ${size * -1.5}px;_x000D_
  top: ${size * -1.5}px;_x000D_
  position: relative;_x000D_
  border-radius: ${size * 3}px ${size * 3}px 0;_x000D_
  transform: rotate(45deg);_x000D_
  border: ${border}px solid #FFFFFF;_x000D_
  `;_x000D_
_x000D_
 let captionStyles = `_x000D_
  transform: rotate(-45deg);_x000D_
  display:block;_x000D_
  width: ${size * 3}px;_x000D_
  text-align: center;_x000D_
  line-height: ${size * 3}px;_x000D_
  `;_x000D_
_x000D_
 let icon = L.divIcon({_x000D_
  className: 'color-pin-' + myCustomColour.replace('#', ''),_x000D_
  iconAnchor: [border, size*2 + border*2],_x000D_
  labelAnchor: [-(size/2), 0],_x000D_
  popupAnchor: [0, -(size*3 + border)],_x000D_
_x000D_
  html: `<span style="${markerHtmlStyles}"><span style="${captionStyles}">${caption || ''}</span></span>`_x000D_
 });_x000D_
_x000D_
 return icon;_x000D_
}_x000D_
_x000D_
var marker = L.marker([lat, lon], {icon: makeMarkerIcon('#123456d0', '?')})_x000D_
.addTo(mymap);

Try the Leaflet.awesome-markers lib -- it allows you to set colors and other styles.

In addition to the way @guillermogfer describe, this is the way to do it if you don't want to paste your whole svg code into your react component. You can just place your svg code in a separate file and load it into your code file as a React Component like this:

import { ReactComponent as SatelliteIcon } from "../assets/icons/satellite.svg";

After you do this you can just use your svg as if it is a react component, so like this:

<SatelliteIcon className="svg-icon light-blue" />

What we ended up doing is define some standard svg colors that are used in our application so we can pass them as a class in order to change the color of the svg. If you don't know the color beforehand or don't have a defined set of colors you can dynamically overwrite the properties in your svg file by using the style attribute, something like this:

<SatelliteIcon style={{ stroke: "black" }}/>

In order for this to work it is important that the attributes you are trying to overwrite are set on the element in your svg and not on the individual paths.

In order to get this svg icon to display in leaflet you can use the divIcon as described by @guillermogfer. However, because the html attribute of the divIcon doesn't understand jsx we need to convert it to string first:

L.divIcon({
    className: 'div-icon',
    html: ReactDOMServer.renderToString(
        <SatelliteIcon className="svg-icon light-blue" />
    )
})

A cheap way to change the Leaflet marker colour is to use the CSS filter property. Give the icon an extra class and then change its colour in the stylesheet:

<style>
img.huechange { filter: hue-rotate(120deg); }
</style>
<script>
var marker = L.marker([y, x]).addTo(map);
marker._icon.classList.add("huechange");
</script>

and this will produce a red marker: alter the value given to hue-rotate to alter the colour.

You can also use the Google Charts API to get icons (just change 'abcdef' with the hexadecimal color you want:

Examples:

• Color '#abcdef':
  • URL: http://chart.apis.google.com/chart?chst=d_map_pin_letter&chld=%E2%80%A2|abcdef&chf=a,s,ee00FFFF
  • Output:
• Color '#e85141':
  • URL: http://chart.apis.google.com/chart?chst=d_map_pin_letter&chld=%E2%80%A2|e85141&chf=a,s,ee00FFFF
  • Output:
• Color '#2ecc71':
  • URL: http://chart.apis.google.com/chart?chst=d_map_pin_letter&chld=%E2%80%A2|2ecc71&chf=a,s,ee00FFFF
  • Output:

Here is the SVG of the icon.

<svg width="28" height="41" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
 <defs>
  <linearGradient id="b">
   <stop stop-color="#2e6c97" offset="0"/>
   <stop stop-color="#3883b7" offset="1"/>
  </linearGradient>
  <linearGradient id="a">
   <stop stop-color="#126fc6" offset="0"/>
   <stop stop-color="#4c9cd1" offset="1"/>
  </linearGradient>
  <linearGradient y2="-0.004651" x2="0.498125" y1="0.971494" x1="0.498125" id="c" xlink:href="#a"/>
  <linearGradient y2="-0.004651" x2="0.415917" y1="0.490437" x1="0.415917" id="d" xlink:href="#b"/>
 </defs>
 <g>
  <title>Layer 1</title>
  <rect id="svg_1" fill="#fff" width="12.625" height="14.5" x="411.279" y="508.575"/>
  <path stroke="url(#d)" id="svg_2" stroke-linecap="round" stroke-width="1.1" fill="url(#c)" d="m14.095833,1.55c-6.846875,0 -12.545833,5.691 -12.545833,11.866c0,2.778 1.629167,6.308 2.80625,8.746l9.69375,17.872l9.647916,-17.872c1.177083,-2.438 2.852083,-5.791 2.852083,-8.746c0,-6.175 -5.607291,-11.866 -12.454166,-11.866zm0,7.155c2.691667,0.017 4.873958,2.122 4.873958,4.71s-2.182292,4.663 -4.873958,4.679c-2.691667,-0.017 -4.873958,-2.09 -4.873958,-4.679c0,-2.588 2.182292,-4.693 4.873958,-4.71z"/>
  <path id="svg_3" fill="none" stroke-opacity="0.122" stroke-linecap="round" stroke-width="1.1" stroke="#fff" d="m347.488007,453.719c-5.944,0 -10.938,5.219 -10.938,10.75c0,2.359 1.443,5.832 2.563,8.25l0.031,0.031l8.313,15.969l8.25,-15.969l0.031,-0.031c1.135,-2.448 2.625,-5.706 2.625,-8.25c0,-5.538 -4.931,-10.75 -10.875,-10.75zm0,4.969c3.168,0.021 5.781,2.601 5.781,5.781c0,3.18 -2.613,5.761 -5.781,5.781c-3.168,-0.02 -5.75,-2.61 -5.75,-5.781c0,-3.172 2.582,-5.761 5.75,-5.781z"/>
 </g>
</svg>

Since you are working with svg elements you could feed your leaflet marker's icon with L.divIcon's html property instead of using iconUrl from L.icon to link your image.

L.marker(latlng, {
    icon: L.divIcon({
        className: 'ship-div-icon',
        html: '<svg>...</svg>'
    })
}).addTo(map);

Then use CSS fill property to color your svg shape. It could be useful to add a class\es to svg's path\s to have precise control

<svg ... >
    <g>
        <path class="ship-icon" ... />
    </g>
    ...
</svg>

At the end, as I also needed to randomly change the marker color I changed directly the path's fill property at the time of creating the marker

var pathFillColor = '#'+(Math.random()*0xFFFFFF<<0).toString(16);

L.marker(latlng, {
    icon: L.divIcon({
        className: 'ship-div-icon',
        html: '<svg ... ><g><path fill="'+pathFillColor+'" ... /> </g></svg>'
    })
}).addTo(map);