leaflet

What is leaflet?

Leaflet is a widely used open-source JavaScript library that helps you create mobile-friendly interactive maps. It provides features that allow users to embed maps into web pages, add various types of layers, markers, popups, and handle user interactions with the map.

What are leaflet's main functionalities?

Map Initialization

This code initializes a new map in the 'mapid' HTML element and sets the view to a specific latitude and longitude and a zoom level.

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

Tile Layer

This code adds a tile layer to the map using OpenStreetMap tiles. It sets the maximum zoom level and adds attribution text.

L.tileLayer('https://{s}.tile.openstreetmap.org/{z}/{x}/{y}.png', {
  maxZoom: 19,
  attribution: '© OpenStreetMap contributors'
}).addTo(map);

Markers

This code places a marker on the map at the specified latitude and longitude.

var marker = L.marker([51.5, -0.09]).addTo(map);

Popups

This code binds a popup with some HTML content to the previously created marker and opens it.

marker.bindPopup('<b>Hello world!</b><br>I am a popup.').openPopup();

GeoJSON

This code adds a GeoJSON layer to the map. The 'geojsonData' variable should contain valid GeoJSON.

L.geoJSON(geojsonData).addTo(map);

Other packages similar to leaflet

openlayers

OpenLayers is an open-source JavaScript library for displaying map data in web browsers. It provides a similar range of features to Leaflet, but it is known for being more feature-rich and customizable, which can make it more complex to use.

mapbox-gl

Mapbox GL JS is a JavaScript library that uses WebGL to render interactive maps from vector tiles and Mapbox styles. It is known for its smooth rendering capabilities and is suitable for applications that require more advanced visual effects and functionalities.

google-maps-react

This package is a wrapper around the Google Maps API for use within React applications. It allows for the integration of Google Maps features, but it requires an API key and is not open-source like Leaflet.

README

Leaflet is the leading open-source JavaScript library for mobile-friendly interactive maps. Weighing just about 37 KB of gzipped JS code, it has all the mapping features most developers ever need.

Leaflet is designed with simplicity, performance and usability in mind. It works efficiently across all major desktop and mobile platforms out of the box, taking advantage of HTML5 and CSS3 on modern browsers while being accessible on older ones too. It can be extended with a huge amount of plugins, has a beautiful, easy to use and well-documented API and a simple, readable source code that is a joy to contribute to.

For more info, docs and tutorials, check out the official website.
For Leaflet downloads (including the built master version), check out the download page.

We're happy to meet new contributors. If you want to get involved with Leaflet development, check out the contribution guide. Let's make the best mapping library that will ever exist, and push the limits of what's possible with online maps!

Changelog

1.0.3 (2017-01-23)

Bug fixes

• Avoid extra L.Canvas redraws on several scenarios (by @perliedman, #5250, also thanks to @manubb for investigation and PR).
• Fix behaviour of dblclick events in Chrome 55 due to PointerEvents (by @IvanSanchez, #5185, #5248, #5268).
• Fix a dangling comma making IE8 fail to parse the code (by @batje, #5270).
• Backport event handling fixes from #5054 into L.SVG.VML for IE8 (by @IvanSanchez, #5215).
• Fix a race condition when closing popups during their popupopen event (by @hagai26, #5202).
• Fix getBoundsZoom return value on CRSs with a flipped axis (by @computerlove, #5204).
• Avoid infinite loops when the errorTileUrl of a L.TileLayer returns 404 (by @IvanSanchez, #5177).
• Remove erroneous initialization of unused event listeners (by @Brikky, #5160).
• Fix rounding of L.Canvas redraw areas to avoid artifacts during partial updates (by @Ernie23, #5148).
• Fix isPopupOpen() behaviour of L.Layer when no popup is bound to a layer (by @gvangool, #5106).
• Add a sanity check in LatLngBounds.contains() to allow for non-instantiated LatLng objects (by @IvanSanchez, #5135).
• Fix collapsing of L.Control.Layers when the collapse option is false (by @perliedman, #5131).

API changes

• Added a new WrapLatLngBounds method to L.CRS, to fix an issue with maxBounds of GridLayers (by @IvanSanchez, #5185, also thanks to @DiogoMCampos for investigation).
• L.Map.getSize() will now return 0 instead of NaN in non-graphical environments (by @ughitsaaron, #5209).

Improvements

• Several minor documentation improvements by @IvanSanchez, @jieter, @alonsogarciapablo, @jasonoverland, @danzel, @ghybs, @Ralf8686, @geoloep
• Add an alt attribute to the <img>s of marker shadows (by @topicus, #5259).