Leaflet.HtmlLegend

A simple Leaflet plugin for creating legends with HTML.

Tested with Leaflet 1.3.x

Install

From NPM:

npm install leaflet-html-legend

Usage

Include the CSS:

<link rel="stylesheet" href="L.Control.HtmlLegend.css" />

Include the JavaScript:

<script src="L.Control.HtmlLegend.min.js"></script>

Control Options:

Option	Type	Default	Description
position	String	'topright'	Map position of element
legend	Array	-	Array of legend entries (see legend options below for details)
collapseSimple	bool	false	Whether to use compact presentation for legend entries that are from a simple renderer
detectStreched	bool	false	Test to see if legend entries look stretched (these are usually in sets of 3 with the middle element having no label)
collapsedOnInit	bool	false	Whether to initialize instance in collapsed mode
updateOpacity	function	null	If set, this function is used to update opacity of the attached layer (it receives the layer and opacity as arguments)
defaultOpacity	number	1	Default opacity for layers in specified in legends
removeIcon	String	'leaflet-html-legend-icon-remove'	css class for the remove icon
visibleIcon	String	'leaflet-html-legend-icon-eye'	css class for the visible icon on opacity slider
hiddenIcon	String	'leaflet-html-legend-icon-eye-slash'	css class for the hidden icon on opacity slider
toggleIcon	String	'leaflet-html-legend-icon-eye-slash'	css class for the icon on visibility toggle button

Legend Options:

Option	Type	Default	Description
name	String	-	Legend label
layer	Leaflet layer	-	The leafel layer to connect to this legend. The legend can control the layer visiblity via opacity slider, if disableVisibilityControls is set to true
allowRemove	boolean	false	Whether to add a remove icon that allows removal of the legend from the control
disableVisibilityControls	bool	false	Whether to add visibility toggle button and opacity slider
elements	Array	-	Array of elements (see element options below for details)

Element options:

Option	Type	Default	Description
label	String	-	Entry label
html	String	-	String representaiton of an HTML elemnt that goes into the legend block
style	Object	-	An object containing css styling of the legend block

You can use addLegend method to add legends to existing instances of HtmlLegend:

var htmlLegend = L.control.htmllegend({...});
htmlLegend.addLegend({
        name: 'Layer name',
        layer: layerInstance,
        elements: [{
            html: '<div>Legend description</div>'
        }]
    })

An existing entry in a legend control instance can be removed using removeLegend. This method needs id of the entry, which can be obtained from htmllegend._entries (see the example for usage).

See the example for usage details.

Contributors:

• Kaveh Karimi