README.md

Google Maps React Markers

Google Maps library that accepts markers as react components and works with React 18+.

It supports a small set of the props of Google Map React. Clustering also is possible. The library implements Google Maps Custom Overlays official library.

If you like this library, please consider supporting me ❤️

💬 Discussion

Released TypeScript version of the library!

Feedbacks are welcome in this discussion.

🚀 Demo

See it in action here (API KEY not provided).

Demo source code is available here.

🛠 Install

pnpm add google-maps-react-markers

or

yarn add google-maps-react-markers

or

npm install --save google-maps-react-markers

💻 Usage

import GoogleMap from 'google-maps-react-markers'

const App = () => {
  const mapRef = useRef(null)
  const [mapReady, setMapReady] = useState(false)

  /**
   * @description This function is called when the map is ready
   * @param {Object} map - reference to the map instance
   * @param {Object} maps - reference to the maps library
   */
  const onGoogleApiLoaded = ({ map, maps }) => {
    mapRef.current = map
    setMapReady(true)
  }

  const onMarkerClick = (e, { markerId, lat, lng }) => {
    console.log('This is ->', markerId)

    // inside the map instance you can call any google maps method
    mapRef.current.setCenter({ lat, lng })
    // ref. https://developers.google.com/maps/documentation/javascript/reference?hl=it
  }

  return (
    <>
      {mapReady && <div>Map is ready. See for logs in developer console.</div>}
      <GoogleMap
        apiKey=""
        defaultCenter={{ lat: 45.4046987, lng: 12.2472504 }}
        defaultZoom={5}
        options={mapOptions}
        mapMinHeight="100vh"
        onGoogleApiLoaded={onGoogleApiLoaded}
        onChange={(map) => console.log('Map moved', map)}
      >
        {coordinates.map(({ lat, lng, name }, index) => (
          <Marker
            key={index}
            lat={lat}
            lng={lng}
            markerId={name}
            onClick={onMarkerClick} // you need to manage this prop on your Marker component!
            // draggable={true}
            // onDragStart={(e, { latLng }) => {}}
            // onDrag={(e, { latLng }) => {}}
            // onDragEnd={(e, { latLng }) => {}}
          />
        ))}
      </GoogleMap>
    </>
  )
}

export default App

🧐 Props

GoogleMap component

Prop	Type	Required	Default	Description
apiKey	string	yes	''	API Key to load Google Maps
defaultCenter	object	yes	{ lat: 0, lng: 0 }	Default center of the map
defaultZoom	number	yes	1-20	Default zoom of the map
libraries	array	no	['places', 'geometry']	Libraries to load
options	object	no	{}	Options for the map
onGoogleApiLoaded	function	no	() => {}	Callback when the map is loaded
onChange	function	no	() => {}	Callback when the map has changed
events	array	no	[]	Array of objects name/handler of DOM events to pass down to the div overlay. Example: events: [{ name: 'onClick', handler: () => {} }]
children	node	no	null	Markers of the map
loadScriptExternally	bool	no	false	Whether to load the Google Maps script externally. If true, the status prop is required and it will be used to control the loading of the script
status	string	no	idle	The forced status of the Google Maps script. Depends on loadScriptExternally. It can be one of idle, loading, ready, error
loadingContent	node	no	'Google Maps is loading'	Content to show while the map is loading
idleContent	node	no	'Google Maps is on idle'	Content to show when the map is idle
errorContent	node	no	'Google Maps is on error'	Content to show when the map has an error
mapMinHeight	string	no	'unset'	Min height of the map
containerProps	object	no	{}	Props for the div container of the map
scriptCallback	function	no	() => {}	window global callback passed to the Google Script
externalApiParams	object	no	undefined	Optional params to pass to the Google API script. Eg. {region: 'IT', language: 'it'}

Markers

Prop	Type	Required	Default	Description
lat	number	yes	undefined	Latitude of the marker
lng	number	yes	undefined	Longitude of the marker
draggable	bool	no	false	If true, the marker can be dragged
onDragStart	func	no	() => {}	This event is fired when the user starts dragging the marker
onDrag	func	no	() => {}	This event is repeatedly fired while the user drags the marker
onDragEnd	func	no	() => {}	This event is fired when the user stops dragging the marker
zIndex	number	no	0	The z-index of the marker. To bring the marker to the front, e.g. when it is active, set a higher value.

📍 Clustering

For clustering, follow this guide using useSupercluster Hook, but use bounds in this way:

const [mapBounds, setMapBounds] = useState({
  bounds: [0, 0, 0, 0],
  zoom: 0,
})
const onMapChange = ({ bounds, zoom }) => {
  const ne = bounds.getNorthEast()
  const sw = bounds.getSouthWest()
  /**
   * useSupercluster accepts bounds in the form of [westLng, southLat, eastLng, northLat]
   * const { clusters, supercluster } = useSupercluster({
   *	points: points,
   *	bounds: mapBounds.bounds,
   *	zoom: mapBounds.zoom,
   * })
   */
  setMapBounds({ ...mapBounds, bounds: [sw.lng(), sw.lat(), ne.lng(), ne.lat()], zoom })
}

👥 Contributing

To run the project locally, clone the repo and run:

# in the root directory
yarn --frozen-install
yarn dev

# in another tab (with NextJS and SSR)
cd docs
yarn install
yarn dev

Do your changes to src/ or docs/src directory, commits all files in the root directory (yarn.lock and ones in dist too) and open a PR.

💻 Built with

• React
• TypeScript
• Google Maps Custom Overlays
• tsup: for bundling
• ESLint: for linting
• Prettier: for code formatting

🗒 License

MIT © giorgiabosello

🙏 Support

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Developed with ❤️ in Italy 🇮🇹