A Leaflet control to add a split screen to compare two map overlays
JavaScript CSS HTML
Latest commit 82223a0 Jun 30, 2016 @gmaclennan gmaclennan committed on GitHub Merge pull request #3 from ghybs/patch-1
Corrected typo in title as well

README.md

leaflet-side-by-side

A Leaflet control to add a split screen to compare two map overlays.

screencast example

L.control.sideBySide(leftLayer[s], rightLayer[s])

Creates a new Leaflet Control for comparing two layers or collections of layers. It does not add the layers to the map - you need to do that manually. Extends L.Control but setPosition() and getPosition are noop because the position is always the same - it does not make sense for this control to be in the corner like other Leaflet controls.

Parameters

parameter type description
leftLayers L.Layer|array A Leaflet Layer or array of layers to show on the left side of the map. Any layer added to the map that is in this array will be shown on the left
rightLayers L.Layer|array A Leaflet Layer or array of layers to show on the right side of the map. Any layer added to the map that is in this array will be shown on the right. These should not be the same as any layers in leftLayers
options Object Options
options.padding Number Padding between slider min/max and the edge of the screen in pixels. Defaults to 44 - the width of the slider thumb

Events

Subscribe to events using these methods

Event Data Description
leftlayeradd LayerEvent Fired when a layer is added to the left-hand-side pane
leftlayerremove LayerEvent Fired when a layer is removed from the left-hand-side pane
rightlayeradd LayerEvent Fired when a layer is added to the right-hand-side pane
rightlayerremove LayerEvent You guessed it... fired when a layer is removed from the right-hand-side pane
dividermove {x: Number} Fired when the divider is moved. Returns an event object with the property x = the pixels of the divider from the left side of the map container.

Methods

Method Returns Description
setLeftLayers this Set the layer(s) for the left side
setRightLayers this Set the layer(s) for the right side

Usage

Add the script to the top of your page (css is included in the javascript):

<script src="leaflet-side-by-side.js"></script>

Or if you are using browserify:

var sideBySide = require('leaflet-side-by-side')

Then create a map, add two layers to it, and create the SideBySide control and add it to the map:

var map = L.map('map').setView([51.505, -0.09], 13);

var myLayer1 = L.tileLayer(...).addTo(map);

var myLayer2 = L.tileLayer(...).addTo(map)

L.control.sideBySide(myLayer1, myLayer2).addTo(map);

Example

Live Example see source

Limitations

  • The divider is not movable with IE.
  • Probably won't work in IE8, but what does?

License

MIT