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React Native Super Cluster

This module wraps AirBnB's react-native-maps and uses MapBox's SuperCluster as clustering engine.

Example

See the showcase application.

Rationale

This module wants to provide a stable and performing solution for maps clustering in React Native. In particular, our efforts are focused on integrating SuperCluster methods into React's state/lifecycle events, ensuring stability, compatibility and great performance.

Install

npm i --save react-native-maps-super-cluster

Usage

NOTES:

  • the prop key of the markers rendered through renderMarker should not be left up to React. Instead, we strongly suggest to use an id in order the have unique keys while still taking advantage of React's recycling
  • ClusteredMapView supports usual React children. Those children won't be affected by clustering, i.e. the behavior for those children is exactly the same as wrapping them around an AirBnB's react-native-maps instance
  • Use onMarkerPress event on MapView instead of using onPress directly on Markers whenever possibile, in particular if you have a lot of pins and clusters. Within onMarkerPress you have access to the marker identifier through the event.nativeEvent attribute, hence you should be able to do everything you would do within an onPress function of a Marker
import React, { Component } from 'react'
import { Marker, Callout } from 'react-native-maps'
import ClusteredMapView from 'react-native-maps-super-cluster'

const INIT_REGION = {
  latitude: 41.8962667,
  longitude: 11.3340056,
  latitudeDelta: 12,
  longitudeDelta: 12
}

export default class MyClusteredMapView extends Component {
  
  ...

  renderCluster = (cluster, onPress) => {
    const pointCount = cluster.pointCount,
          coordinate = cluster.coordinate,
          clusterId = cluster.clusterId

    // use pointCount to calculate cluster size scaling
    // and apply it to "style" prop below

    // eventually get clustered points by using
    // underlying SuperCluster instance
    // Methods ref: https://github.com/mapbox/supercluster
    const clusteringEngine = this.map.getClusteringEngine(),
          clusteredPoints = clusteringEngine.getLeaves(clusterId, 100)

    return (
      <Marker coordinate={coordinate} onPress={onPress}>
        <View style={styles.myClusterStyle}>
          <Text style={styles.myClusterTextStyle}>
            {pointCount}
          </Text>
        </View>
        {
          /*
            Eventually use <Callout /> to
            show clustered point thumbs, i.e.:
            <Callout>
              <ScrollView>
                {
                  clusteredPoints.map(p => (
                    <Image source={p.image}>
                  ))
                }
              </ScrollView>
            </Callout>

            IMPORTANT: be aware that Marker's onPress event isn't really consistent when using Callout.
           */
        }
      </Marker>
    )
  }

  renderMarker = (data) => <Marker key={data.id || Math.random()} coordinate={data.location} />

  ...

  render() {
    return (
      <ClusteredMapView
        style={{flex: 1}}
        data={this.state.data}
        initialRegion={INIT_REGION}
        ref={(r) => { this.map = r }}
        renderMarker={this.renderMarker}
        renderCluster={this.renderCluster} />
    )
  }
}

Props

Name Type Required Default Note
radius Number false window width * 4,5% SuperCluster radius.
extent Number false 512 SuperCluster extent.
minZoom Number false 1 SuperCluster minZoom.
maxZoom Number false 20 SuperCluster maxZoom.
width Number false window width map's width.
height Number false window height map's height.
data Array true undefined Objects must have an attribute location representing a GeoPoint, i.e. { latitude: x, longitude: y }.
onExplode Function false undefined TODO
onImplode Function false undefined TODO
onClusterPress(clusterId, ?children) Function false Add (or completey override) behaviours to the clusterPress handler. children is passed when default behavior is preserved (see preserveClusterPressBehavior prop).
preserveClusterPressBehavior Bool false true Whether onClusterPress prop should completely override module's behavior rather than integrate it.
clusterPressMaxChildren Function false 100 Max number of cluster leaves returned as second parameter of onClusterPress.
edgePadding Object false { top: 10, left: 10, bottom: 10, right: 10 } Edge padding for react-native-maps's fitToCoordinates method, called in onClusterPress for fitting to pressed cluster children.
renderMarker Function false undefined Must return a react-native-maps' Marker component.
animateClusters Bool false true Animate imploding/exploding of clusters' markers and clusters size change. Works only on iOS.
clusteringEnabled Bool false true Dynamically set whether to pass through clustering functions or immediately render markers as a normal mapview.
scaleUpRatio(markersCount: Number); Function false undefined Must return a number, used to multiply clusters and font sizes based on markersCount. Deprecated, use renderCluster instead.
clusterInitialFontSize Number false 12 font base size for cluster counter. Scales up proportionally to clustered markers. Deprecated, use renderCluster instead.
clusterInitialDimension Number false 30 cluster view base dimension in dpi/ppi. Scales up proportionally to clustered markers. Deprecated, use renderCluster instead.
textStyle Object false NovaLab Brand colors Style of the Text component used for clusters counters. Deprecated, use renderCluster instead.
containerStyle Object false NovaLab Brand colors Style of the clusters View. Deprecated, use renderCluster instead.

Methods

Name Params Description Note
getMapRef none Getter for underlying react-native-maps instance Official Doc
getClusteringEngine none Getter for underlying SuperCluster instance Official Doc

Production usage

If you are using this module in a production application, please submit a PR or contact us to add it here.

TODO

features

  • improve scaleUpRatio math for fontSize
  • trigger events on cluster implode/explode

Contributors

License

See our License for more information.

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A Clustering-enabled map for React Native

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