I want to add some very small custom divIcon markers to a Leaflet (v1.9.3) map. However, it seems icons smaller than [14,14] do not align at the center of the marker. Following image shows three markers at same location with a circle SVG as the divIcon and radii of 50,20,6. Notice the first two center but the 6px one is off center:
Some control can be had with iconAnchor but seems the value would need to vary depending on iconSize and the computation isn't obvious to me. Is there a better way to center align small divIcons like above?
Code for above image:
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8" />
<link rel="stylesheet" href="https://unpkg.com/leaflet#1.9.3/dist/leaflet.css" integrity="sha256-kLaT2GOSpHechhsozzB+flnD+zUyjE2LlfWPgU04xyI=" crossorigin="" />
<script src="https://unpkg.com/leaflet#1.9.3/dist/leaflet.js" integrity="sha256-WBkoXOwTeyKclOHuWtc+i2uENFpDZ9YPdf5Hf+D7ewM=" crossorigin=""></script>
<style type='text/css'>
html, body { margin: 0; padding: 0; border: 0; }
#map { height: 100vh; }
</style>
<script>
var map;
var myIcon = (color = 'red', b = 24) => `
<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 ${b} ${b}">
<circle fill="${color}" cx="${b/2}" cy="${b/2}" r="${b/2}" />
</svg>`;
function init() {
var map = L.map('map').setView([50.0, 0.0], 13);
L.tileLayer('http://{s}.tile.openstreetmap.org/{z}/{x}/{y}.png', {
maxZoom: 18
}).addTo(map);
var marker = L.marker(
[51.5, -0.09], {
icon: L.divIcon({
html: myIcon('red', 50),
iconSize: [50,50],
className: ''
}),
}).addTo(map);
var marker = L.marker(
[51.5, -0.09], {
icon: L.divIcon({
html: myIcon('green', 20),
iconSize: [20,20],
className: ''
}),
}).addTo(map);
var marker = L.marker(
[51.5, -0.09], {
icon: L.divIcon({
html: myIcon('blue', 6),
iconSize: [6,6],
className: ''
}),
}).addTo(map);
map.panTo(marker.getLatLng());
}
</script>
</head>
<body onload='init();'>
<div id="map"></div>
</body>
</html>
Solution: set style="display: block" on the <svg> element. <svg> elements are use display: inline by default which uses some flow layouting algorithm.
<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 6 6" style="display: block">
<circle fill="blue" cx="3" cy="3" r="3"></circle>
</svg>
Related
<div id='map' style='width: 400px; height: 300px;'></div>
<script>
mapboxgl.accessToken = 'TOKEN';
var map = new mapboxgl.Map({
container: '<your HTML element id>',
style: 'mapbox://styles/mapbox/streets-v11', // stylesheet location
center: [-74.5, 40], // starting position [lng, lat]
zoom: 9 // starting zoom
});
</script>
I have this code working with my custom style, but anytime I try to modify it, the page turns blank. If I change the center, the zoom, or the width or the height, nothing shows up. I'm not sure what I'm doing wrong. It's my first Mapbox attempt.
Thanks!
Can you post the modified code that is not working please? The code that you have provided is incomplete.
Please try out the below code to display a map. Please ensure to replace <ACCESS_TOKEN> with your access token:
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8" />
<title>Display a map</title>
<meta name="viewport" content="initial-scale=1,maximum-scale=1,user-scalable=no" />
<script src="https://api.mapbox.com/mapbox-gl-js/v1.11.0/mapbox-gl.js"></script>
<link href="https://api.mapbox.com/mapbox-gl-js/v1.11.0/mapbox-gl.css" rel="stylesheet" />
<style>
body { margin: 0; padding: 0; }
#map { position: absolute; top: 0; bottom: 0; width: 100%; }
</style>
</head>
<body>
<div id="map"></div>
<script>
mapboxgl.accessToken = '<ACCESS_TOKEN>';
var map = new mapboxgl.Map({
container: 'map', // container id
style: 'mapbox://styles/mapbox/streets-v11', // stylesheet location
center: [-74.5, 40], // starting position [lng, lat]
zoom: 9 // starting zoom
});
</script>
</body>
</html>
I'm trying to build out the functionality to measure a line that a user draws over a Mapbox map, using turf.js 'length' feature.
That said, I'm a coding newb - I know just barely enough to be dangerous.
Ultimately I'd like to be able to draw both areas and lines, and have their respective measures returned (area for polygons, lengths for line strings).
Can anyone offer insight as to why this code doesn't work?
https://jsfiddle.net/knxwu342
<html>
<head>
<meta charset=utf-8 />
<title>Line Test</title>
<meta name='viewport' content='initial-scale=1,maximum-scale=1,user-scalable=no' />
<style>
body { margin:0; padding:0; }
#map { position:absolute; top:0; bottom:0; width:100%; }
.calculation-box-length {
height: 75px;
width: 100px;
position: absolute;
bottom: 40px;
left: 10px;
background-color: rgba(255, 255, 255, .9);
padding: 15px;
text-align: center;
}
</style>
<script src='https://api.tiles.mapbox.com/mapbox.js/plugins/turf/v3.0.11/turf.min.js'>
</script>
<script src='https://api.mapbox.com/mapbox-gl-js/plugins/mapbox-gl-draw/v1.0.9/mapbox-gl-draw.js'></script>
<link rel='stylesheet' href='https://api.mapbox.com/mapbox-gl-js/plugins/mapbox-gl-draw/v1.0.9/mapbox-gl-draw.css' type='text/css'/>
<script src='https://api.tiles.mapbox.com/mapbox-gl-js/v0.45.0/mapbox-gl.js'>
</script>
<link href='https://api.tiles.mapbox.com/mapbox-gl-js/v0.45.0/mapbox-gl.css' rel='stylesheet' />
</head>
<body>
<div id='map'></div>
<div class='calculation-box-length'>
<p>Length:</p>
<div id='calculated-length'></div>
</div>
<nav id="menu"></nav>
<script>mapboxgl.accessToken = 'pk.eyJ1IjoibWJsYWNrbGluIiwiYSI6ImNqaWMxcGk2MzAwd3YzbG1oeW4yOHppdnYifQ.xdb-2slu5LapzpuMCiKzQQ';
//*********-----------------------------------------------------------------------------------------------------------------**********
//Create new map object
var map = new mapboxgl.Map({
container: 'map', // container id
style: 'mapbox://styles/mblacklin/cjii8o7w91g9o2stcktaeixai', // stylesheet location
center: [-117.572737, 51.746916], // starting position [lng, lat]
zoom: 16 // starting zoom
});
//*********-----------------------------------------------------------------------------------------------------------------**********
// Add navigation controls to the map
map.addControl(new mapboxgl.NavigationControl());
//*********-----------------------------------------------------------------------------------------------------------------**********
// Add the ability to draw geometries and display their measurements
//
var draw = new MapboxDraw({
displayControlsDefault: false,
controls: {
line_string: true,
polygon: true,
trash: true
}
});
map.addControl(draw);
map.on('draw.create.', updateLength);
map.on('draw.delete', updateLength);
map.on('draw.update', updateLength);
function updateLength(e) {
var data = draw.getAll();
var answer = document.getElementById('calculated-length');
if (data.features.length > 0) {
var length = turf.length(data);
// restrict to area to 2 decimal points
answer.innerHTML = '<p><strong>' + length + '</strong></p><p> meters</p>';
} else {
answer.innerHTML = '';
if (e.type !== 'draw.delete') alert("Use the draw tools in the upper right to calculate a distance");
}
};
//
//*********-----------------------------------------------------------------------------------------------------------------**********
</script>
</body>
</html>
I see two little problems in your code:
There is a typo in your 'draw.create' listener. Just remove the point after create:
map.on('draw.create', updateLength);
The version of Turf you are using is too old and does not seem to have the length function. Try using the most recent one: https://npmcdn.com/#turf/turf/turf.min.js
I have this code that works fine, but I need to get only the icon to show and not the "balloon" with its shadow.
I have tried with removing "markerColor..." but that is only changing to the default blue marker / balloon.
How to only show the icon and its size and color?
pointToLayer: function(feature, latlng) {
var con = feature.properties.concept;
var hub;
// icons for XX, YY and ZZ
if (kon === 'XX') {
hub = new L.marker(latlng, {icon: L.AwesomeMarkers.icon({icon: 'truck', prefix: 'fa', markerColor: 'cadetblue'}) });
} else if (kon === 'YY') {
hub = new L.marker(latlng, {icon: L.AwesomeMarkers.icon({icon: 'envelope', prefix: 'fa', markerColor: 'blue'}) });
} else if (kon === 'ZZ') {
hub = new L.marker(latlng, {icon: L.AwesomeMarkers.icon({icon: 'bicycle', prefix: 'fa', markerColor: 'darkblue'}) });
} else {
hub = new L.marker(latlng, {icon: L.AwesomeMarkers.icon({icon: 'envelope-o', prefix: 'fa', markerColor: 'red'}) });
}
return hub;
}
Unfortunately, Leaflet.awesome-markers plugin does not offer you the option to display only the inner icon (from Font Awesome or whatever source) without the surrounding balloon.
Same for its cloned version and other variations like Leaflet.extra-markers plugin.
But you can very simply use a Leaflet DivIcon instead:
Represents a lightweight icon for markers that uses a simple <div> element instead of an image. Inherits from Icon but ignores the iconUrl and shadow options.
Then you simply fill that <div> container with your Font Awesome icon, the same way you would do it in a normal page, and what the Leaflet.awesome-markers plugin does under the hood for you:
L.marker(latlng, {
icon: L.divIcon({
html: '<i class="fa fa-truck" style="color: red"></i>',
iconSize: [20, 20],
className: 'myDivIcon'
})
});
Note that you also have to specify a bit of CSS to customize it as you wish:
.myDivIcon {
text-align: center; /* Horizontally center the text (icon) */
line-height: 20px; /* Vertically center the text (icon) */
}
Example:
var map = L.map('map').setView([48.86, 2.35], 11);
L.marker([48.86, 2.35], {
icon: L.divIcon({
html: '<i class="fa fa-truck" style="color: red"></i>',
iconSize: [20, 20],
className: 'myDivIcon'
})
}).addTo(map);
L.tileLayer('https://{s}.tile.openstreetmap.org/{z}/{x}/{y}.png', {
attribution: '© OpenStreetMap contributors'
}).addTo(map);
.myDivIcon {
text-align: center; /* Horizontally center the text (icon) */
line-height: 20px; /* Vertically center the text (icon) */
}
<link rel="stylesheet" href="https://unpkg.com/leaflet#1.3.1/dist/leaflet.css" integrity="sha512-Rksm5RenBEKSKFjgI3a41vrjkw4EVPlJ3+OiI65vTjIdo9brlAacEuKOiQ5OFh7cOI1bkDwLqdLw3Zg0cRJAAQ==" crossorigin="" />
<script src="https://unpkg.com/leaflet#1.3.1/dist/leaflet-src.js" integrity="sha512-IkGU/uDhB9u9F8k+2OsA6XXoowIhOuQL1NTgNZHY1nkURnqEGlDZq3GsfmdJdKFe1k1zOc6YU2K7qY+hF9AodA==" crossorigin=""></script>
<link rel="stylesheet" href="https://unpkg.com/leaflet.awesome-markers#2.0.4/dist/leaflet.awesome-markers.css" />
<script src="https://unpkg.com/leaflet.awesome-markers#2.0.4/dist/leaflet.awesome-markers.js"></script>
<link href="https://use.fontawesome.com/releases/v5.0.8/css/all.css" rel="stylesheet">
<div id="map" style="height: 180px"></div>
I am using Mapbox GL JS and I would like to allow users to change a map's background style from streets to satellite, while showing a polygon layer above the map background.
I have adapted the Mapbox example, but I can't work out how to stop map.setStyle from setting the new style above (and thus hiding) my polygon layer. I would like it to change without hiding the polygon layer.
Before switching layers:
After switching layers - polygon overlay missing, would like to carry on showing it:
This is my code in full:
<!DOCTYPE html>
<html>
<head>
<meta charset='utf-8' />
<title></title>
<meta name='viewport' content='initial-scale=1,maximum-scale=1,user-scalable=no' />
<script src='https://api.tiles.mapbox.com/mapbox-gl-js/v0.33.1/mapbox-gl.js'></script>
<link href='https://api.tiles.mapbox.com/mapbox-gl-js/v0.33.1/mapbox-gl.css' rel='stylesheet' />
<style>
body { margin:0; padding:0; }
#map { position:absolute; top:0; bottom:0; width:100%; }
</style>
</head>
<body>
<style>
#menu {
position: absolute;
background: #fff;
padding: 10px;
font-family: 'Open Sans', sans-serif;
}
</style>
<div id='map'></div>
<div id='menu'>
<input id='basic' type='radio' name='rtoggle' value='basic' checked='checked'>
<label for='basic'>basic</label>
<input id='satellite' type='radio' name='rtoggle' value='satellite'>
<label for='satellite'>satellite</label>
</div>
<script>
mapboxgl.accessToken = 'pk.eyTOKEN';
var map = new mapboxgl.Map({
container: 'map',
style: 'mapbox://styles/mapbox/basic-v9',
zoom: 5,
center: [-3.0, 54.6]
});
map.on('load', function () {
map.addSource('xxx', {
type: 'vector',
url: 'mapbox://xxx.xxx'
});
map.addLayer({
'id': 'xxx',
'source': 'xxx',
'type': 'fill',
'paint': {
'fill-color': 'red'
},
'source-layer': mylayer
}, 'road'); // Note that I'd like this to display above the OSM 'roads' layer
var layerList = document.getElementById('menu');
var inputs = layerList.getElementsByTagName('input');
function switchLayer(layer) {
var layerId = layer.target.id;
map.setStyle('mapbox://styles/mapbox/' + layerId + '-v9');
}
for (var i = 0; i < inputs.length; i++) {
inputs[i].onclick = switchLayer;
}
});
</script>
</body>
</html>
Mapbox GL JS does not have the concept of a "base layer" and "overlays." All layers of all maps are drawn with the same basic primitives.
If you need to persist one or more custom layers while switching between the provided Mapbox styles, you may choose to
fork the Mapbox style and add your custom layers in Studio
re-add your custom layers after switching styles
download the Mapbox style as JSON in the browser and add your custom layers to the style in the browser
I would like to trigger an extra event when clicking on a marker. Now, it opens a popup, but instead I would like to show the information in an extra info layer. I have managed to show the layer (var info), but I don't know how to change the information with a click on the marker.
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Schönberg Topography</title>
<link rel="stylesheet" href="../lib/mapbox.css" />
<script src="../lib/mapbox.js"></script>
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<link rel="stylesheet" href="../dist/MarkerCluster.css" />
<link rel="stylesheet" href="../dist/MarkerCluster.Default.css" />
<script src="../dist/leaflet.markercluster-src.js"></script>
<script charset="UTF-8" src="topography.js"></script>
<style>
body {
padding: 0;
margin: 0;
}
html,
body,
#map {
height: 100%;
}
.info {
padding: 6px 8px;
font: 14px/16px Arial, Helvetica, sans-serif;
background: white;
background: rgba(255, 255, 255, 0.8);
box-shadow: 0 0 15px rgba(0, 0, 0, 0.2);
border-radius: 5px;
}
.info h4 {
margin: 0 0 5px;
color: #777;
}
</style>
<style type="text/css">
a:link {
text-decoration: none;
}
</style>
</head>
<meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no" />
<body>
<div id="map"></div>
<script type="text/javascript">
var cloudmadeUrl = 'http://otile1.mqcdn.com/tiles/1.0.0/osm/{z}/{x}/{y}.png',
cloudmadeAttribution = 'Map data © 2011 OpenStreetMap contributors, Imagery © 2011 Mapbox, Points © 2012 LINZ',
cloudmade = new L.TileLayer(cloudmadeUrl, {
maxZoom: 17,
attribution: cloudmadeAttribution
}),
latlng = new L.LatLng(48.86, 2.34);
var map = new L.Map('map', {
center: latlng,
zoom: 12,
maxBounds: [
[49, 2.7],
[48.7, 2, 45]
],
layers: [cloudmade]
});
var markers = new L.MarkerClusterGroup();
for (var i = 0; i < addressPoints.length; i++) {
var a = addressPoints[i];
var title = a[2];
var name = a[3]
var colormarker = a[4]
var typemarker = a[5]
var marker = L.marker(new L.LatLng(a[0], a[1]), {
icon: L.mapbox.marker.icon({
'marker-symbol': typemarker,
'marker-color': colormarker
}),
title: name
});
var info = L.control();
info.onAdd = function() {
this._div = L.DomUtil.create('div', 'info'); // create a div with a class "info"
this.update();
return this._div;
};
// method that we will use to update the control based on feature properties passed
info.update = function() {
this._div.innerHTML = title;
};
marker.bindPopup(title);
markers.addLayer(marker);
}
map.addLayer(markers);
info.addTo(map);
</script>
</body>
</html>
You would need to modify your update function to take a parameter to begin here.You also only need to be creating this info control once, not each time inside the loop..because you only need one open at a time, right?
info.update = function(content) {
this._div.innerHTML = content;
};
Don't forget to update your onAdd with regards to removing the update.
info.onAdd = function() {
this._div = L.DomUtil.create('div', 'info'); // create a div with a class "info"
return this._div;
};
Then, inside the callback for a click event on a marker, you would call info.update("My new content").