react-simple-maps
An svg map component built with and for React. It allows the creation of pure react svg maps.
Why
React-simple-maps
aims to make working with svg maps in react easier. It handles tasks such as panning, zooming and simple rendering optimization, and takes advantage of parts of d3-geo and topojson-client instead of relying on the entire d3 library.
Since react-simple-maps
leaves DOM work to react, it can also be easily used with other libraries, such as react-motion and redux-tooltip.
API changes from 0.9 to 0.10
In version 0.10
the method of passing geography data to react-simple-maps
has changed. Where previously geographyUrl
and geographyPaths
were separate, they are now handled together through the geography
prop. If you are upgrading from version 0.9
, simply change geographyUrl
or geographyPaths
to geography
and you should be good to go.
Installation
To install react-simple-maps
$ npm install react react-dom react-simple-maps --save
Usage
React-simple-maps
exposes a set of components that can be combined to create svg maps with markers and annotations. In order to render a map you have to provide a reference to a valid topojson file. You can find example topojson files in the topojson-maps
folder or on topojson world-atlas. To learn how to make your own topojson maps from shapefiles, please read "How to convert and prepare TopoJSON files for interactive mapping with d3" on medium.
import React, { Component } from "react"
import ReactDOM from "react-dom"
import {
ComposableMap,
ZoomableGroup,
Geographies,
Geography,
} from "react-simple-maps"
class App extends Component {
render() {
return(
<div>
<ComposableMap>
<ZoomableGroup>
<Geographies geography={ "/path/to/your/topojson-map-file.json or geography object" }>
{(geographies, projection) => geographies.map(geography => (
<Geography
key={ geography.id }
geography={ geography }
projection={ projection }
/>
))}
</Geographies>
</ZoomableGroup>
</ComposableMap>
</div>
)
}
}
document.addEventListener("DOMContentLoaded", () => {
ReactDOM.render(<App />, document.getElementById("app"))
})
Here is the complete simplified component structure of any map created with react-simple-maps
.
<ComposableMap>
<ZoomableGroup>
<Geographies geography={ "/path/to/your/topojson-map-file.json or geography object" }>
{(geographies, projection) => geographies.map(geography => (
<Geography key={ geography.id } geography={ geography } projection={ projection } />
))}
</Geographies>
<Markers>
<Marker />
</Markers>
<Annotation />
</ZoomableGroup>
</ComposableMap>
The above results in the following svg structure rendered by react:
<svg class="rsm-svg">
<g class="rsm-zoomable-group">
<g class="rsm-geographies">
<path class="rsm-geography" />
<path class="rsm-geography" />
<path class="rsm-geography" />
...
</g>
<g class="rsm-markers">
<g class="rsm-marker"></g>
</g>
<g class="rsm-annotation"></g>
</g>
</svg>
Components
React-simple-maps
is a set of components that simplify the process of making interactive svg maps with react. The components included are:
<ComposableMap />
<ComponentMap />
forms the wrapper around your map. It defines the dimensions of the map and sets the projection used by Geographies, Markers, and Annotations, to position elements. By default the maps use the "times" projection, but react-simple-maps
also supports robinson
, eckert4
, winkel3
, mercator
, and miller
projections out of the box. Additionally you can plug in a custom projection of your choice. All projections from d3-geo-projections
are supported.
Props
Property | Type | Default |
---|
width | Number | 800 |
height | Array | 450 |
projection | String/Function | "times" |
projectionConfig | Object | *see examples below |
Configuring projections
The following custom configuration would prevent a visual split of Russia.
...
<ComposableMap
projectionConfig={{
scale: 200,
rotation: [-10,0,0],
}}
>
...
</ComposableMap>
...
The default configuration of the projection:
{
scale: 160,
xOffset: 0,
yOffset: 0,
rotation: [0,0,0],
precision: 0.1,
}
<ZoomableGroup />
<ZoomableGroup />
is a component that allows you to zoom and pan. Check out the zoom example to find out how to work with zoom in react-simple-maps
.
Props
Property | Type | Default |
---|
zoom | Number | 1 |
center | Array | [0,0] |
disablePanning | Boolean | false |
style | Object | {} |
onMoveStart | Function | |
onMoveEnd | Function | |
Zooming
The ZoomableGroup
component exposes a zoom property, which can be updated from a wrapper component via setState.
import React, { Component } from "react"
import ReactDOM from "react-dom"
import {
ComposableMap,
ZoomableGroup,
Geographies,
Geography,
} from "react-simple-maps"
class App extends Component {
constructor() {
super()
this.state = {
zoom: 1,
}
this.handleZoomIn = this.handleZoomIn.bind(this)
this.handleZoomOut = this.handleZoomOut.bind(this)
}
handleZoomIn() {
this.setState({
zoom: this.state.zoom * 2,
})
}
handleZoomOut() {
this.setState({
zoom: this.state.zoom / 2,
})
}
render() {
return(
<div>
<button onClick={ this.handleZoomIn }>{ "Zoom in" }</button>
<button onClick={ this.handleZoomOut }>{ "Zoom out" }</button>
<hr />
<ComposableMap>
<ZoomableGroup zoom={ this.state.zoom }>
<Geographies geography={ "/path/to/your/topojson-map-file.json or geography object" }>
{(geographies, projection) => geographies.map(geography => (
<Geography
key={ geography.id }
geography={ geography }
projection={ projection }
/>
))}
</Geographies>
</ZoomableGroup>
</ComposableMap>
</div>
)
}
}
document.addEventListener("DOMContentLoaded", () => {
ReactDOM.render(<App />, document.getElementById("app"))
})
Move events
The ZoomableGroup
component allows you to hook into the onMoveStart
and onMoveEnd
event, and exposes the new center of the map in the callback.
handleMoveStart(currentCenter) {
console.log("New center: ", currentCenter)
}
handleMoveEnd(newCenter) {
console.log("New center: ", newCenter)
}
...
<ZoomableGroup
onMoveStart={this.handleMoveStart}
onMoveEnd={this.handleMoveEnd}
>
<Geographies>
...
</Geographies>
</ZoomableGroup>
...
<Geographies />
<Geographies />
is a group wrapper around the geographies paths. It returns a function that contains the geographies extracted from the data passed ot the geography
prop.
React-simple-maps offers a couple of ways to optimise the performance of the map:
-
By default the <Geographies />
component uses shouldComponentUpdate
to prevent the paths from being rerendered. This optimisation can be bypassed using the disableOptimization
prop. This is useful when making choropleth maps that are updated on user interaction.
-
A second way in which react-simple-maps can optimise maps is by setting a cacheId
on the individual geographies. See the <Geography />
component for more info. The unique cacheIds help to cache the paths and significantly accelerate rerenders. This second method is the recommended way of optimising maps with react-simple-maps.
If you do not want react-simple-maps
to load your topojson and pass it down automatically, you can also pass your topojson converted features
directly into the Geographies
component, or an object containing the topojson data.
Props
Property | Type | Default |
---|
disableOptimization | Boolean | false |
geography | String or Object, or Array | "" |
Choropleth map
The below example uses the world-50m.json TopoJSON file.
import React, { Component } from "react"
import { scaleLinear } from "d3-scale"
import geographyObject from "/path/to/world-50m.json"
const colorScale = scaleLinear()
.domain([0, 100000000, 1338612970])
.range(["#FFF176", "#FFC107", "#E65100"])
class ChoroplethMap extends Component {
render() {
return (
<div>
<ComposableMap style={{ width: "100%" }}>
<ZoomableGroup>
<Geographies geography={ "/path/to/world-50m.json or geography object" } disableOptimization> // if you are using the object, then geography={geographyObject}
{(geographies, projection) => geographies.map((geography, i) => (
<Geography
key={ `geography-${i}` }
cacheId={ `geography-${i}` }
geography={ geography }
projection={ projection }
style={{
default: {
fill: colorScale(geography.properties.pop_est),
stroke: "#FFF",
strokeWidth: 0.5,
outline: "none",
},
}}
/>
))}
</Geographies>
</ZoomableGroup>
</ComposableMap>
</div>
)
}
}
export default ChoroplethMap
Custom TopoJSON via geography
If you want to transform your own TopoJSON maps with topojson-client
, you can use geography
prop to inject your own array of paths into react-simple-maps
.
import React, { Component } from "react"
import { get } from "axios"
import { feature } from "topojson-client"
class CustomMap extends Component {
contructor() {
super()
this.state = {
geographyPaths: [],
}
this.loadPaths = this.loadPaths.bind(this)
}
componentDidMount() {
this.loadPaths()
}
loadPaths() {
get("/path/to/world-topojson.json")
.then(res => {
if (res.status !== 200) return
const world = res.data
const geographyPaths = feature(
world,
world.objects[Object.keys(world.objects)[0]]
).features
this.setState({ geographyPaths })
})
}
render() {
return (
...
<Geographies geography={this.state.geographyPaths} disableOptimization>
...
</Geographies>
...
)
}
Check out the custom-json-geographyPaths example to see how to do this.
<Geography />
The <Geography />
component represents each shape converted with topojson. The component can be used to assign events to individual shapes on the map, and to specify their hover, focus and click behavior.
Props
Property | Type | Default |
---|
cacheId | Number/String | null |
precision | Number | 0.1 |
round | Boolean | false |
geography | Object | *see examples below |
tabable | Boolean | true |
style | Object | *see examples below |
Styling
There are no default styles assigned to the <Geography />
component. Since the geography paths have to be optimized in order to allow for decent performance, the styles have to be handled by the <Geography />
component internally. The style prop is an object that defines three states for each path.
...
<Geography style={{
default: { fill: "#666" },
hover: { fill: "#999" },
pressed: { fill: "#000" },
}}/>
...
Geography events and accessing geography data in events
...
handleClick(geography, evt) {
console.log("Geography data: ", geography)
}
...
<Geographies geography={ "/path/to/your/topojson-map-file.json" }>
{(geographies, projection) => geographies.map((geography, i) => (
<Geography
key={ i }
geography={ geography }
projection={ projection }
onClick={this.handleClick}
/>
))}
</Geographies>
...
Currently supported events are onMouseEnter
, onMouseLeave
, onMouseDown
, onMouseUp
, onClick
, onMouseMove
, onFocus
, onBlur
.
<Markers />
<Markers />
is a simple wrapper component for the individual markers.
<Marker />
The <Marker />
component represents each marker and uses coordinates to position the marker on the map. It does not make any assumptions about what your marker looks like, so you have to specify yourself what shape it should have. See the example below for how to make the recommended circular marker. The component can be used to assign events to individual markers on the map, and to specify the hover, focus and click behavior. You can also choose to preserve the markers aspect/size when in a <ZoomableGroup />
via the preserveMarkerAspect
prop.
Props
Property | Type | Default |
---|
marker | Object | *see below examples |
tabable | Boolean | true |
style | Object | *see below examples |
preserveMarkerAspect | Boolean | true |
Marker location
Marker data is added to the marker
prop and should contain the coordinates of the marker.
<Markers>
<Marker marker={{ coordinates: [ 8.5, 47.3 ] }}>
<circle cx={ 0 } cy={ 0 } r={ 10 } />
</Marker>
</Markers>
Styling and shape
There are no styles assigned to the style prop, and the marker does not have a shape by default.
...
<Marker
marker={{ coordinates: [ 8.5, 47.3 ] }}
style={{
default: { fill: "#666" },
hover: { fill: "#999" },
pressed: { fill: "#000" },
}
}>
<circle cx={ 0 } cy={ 0 } r={ 10 } />
</Marker>
...
Marker events and passing marker data to marker events
In order to allow easy access to marker data when handling events, pass the marker data to the marker
prop. Below is an example of how to iterate through markers.
...
handleClick(marker, evt) {
console.log("Marker data: ", marker)
}
...
<Markers>
{ markers.map((marker, i) => (
<Marker
key={ i }
marker={ marker }
onClick={ this.handleClick }
/>
))}
</Markers>
...
Currently supported events are onMouseEnter
, onMouseLeave
, onMouseDown
, onMouseUp
, onClick
, onMouseMove
, onFocus
, onBlur
.
<Annotations />
<Annotations />
is a simple wrapper component for the individual annotations.
<Annotation />
<Annotation />
components can be used to add textual annotations. To position an annotation you have to specify the coordinates of the subject of the annotation, and then pass in numbers for dx and dy to specify the offset of the annotation itself.
Props
Property | Type | Default |
---|
subject | Array | [0,0] |
dx | Number | 30 |
dy | Number | 30 |
zoom | Number | 1 |
stroke | String | "#000000" |
strokeWidth | Number | 1 |
style | Object | {} |
markerEnd | String | "none" |
curve | Number | 0 |
Example annotation
The following example shows how to add a sample annotation for the city of Zurich on a world map.
...
<Annotation dx={ -30 } dy={ 30 } subject={ [ 8.5, 47.3 ] } strokeWidth={ 1 }>
<text>
{ "Zurich" }
</text>
</Annotation>
...
You can also use the <Annotations />
component to iterate over annotations.
...
<Annotations>
{
annotations.map((annotation, i) => (
<Annotation
key={i}
dx={ -30 }
dy={ 30 }
subject={ annotation.coordinates }
strokeWidth={ 1 }
>
<text>
{ annotation.label }
</text>
</Annotation>
))
}
</Annotations>
...
Annotations with a curved connector
The following example shows how to add an annotation with a curved connector for the city of Zurich on a world map. The curve
prop can take either a positive number (e.g. 0.5), or a negative number (e.g. -0.5) to create connectors with varying curve intensity. The default value of 0 will connect the annotation through a straight line with no curve.
...
<Annotation
dx={ -30 }
dy={ 30 }
subject={ [ 8.5, 47.3 ] }
strokeWidth={ 1 }
curve={0.5}
>
<text>
{ "Zurich" }
</text>
</Annotation>
...
Annotations with an arrow connector
To make the connector an arrow, you can pass a custom SVG marker id to the markerEnd
prop of the <Annotation />
component.
...
<Annotation
dx={ -30 }
dy={ 30 }
subject={ [ 8.5, 47.3 ] }
stroke="#000"
strokeWidth={ 1 }
curve={0.5}
markerEnd="url(#custom-arrow)"
>
<defs>
<marker
id="custom-arrow"
markerWidth={10}
markerHeight={10}
refX={7}
refY={5}
orient="auto"
markerUnits="userSpaceOnUse"
>
<path
d="M1,1 L7,5 L1,9"
fill="none"
stroke="#000"
strokeWidth={1}
/>
</marker>
</defs>
<text>
{ "Zurich" }
</text>
</Annotation>
...
<Graticule />
The <Graticule />
component can be used to add a graticule to the map. Note that you can place the graticule before (behind) or after (on top of) the other elements.
Props
Property | Type | Default |
---|
step | Array | [10,10] |
round | Boolean | true |
precision | Nmber | 0.1 |
outline | Boolean | true |
stroke | String | "#DDDDDD" |
fill | String | "transparent" |
style | Object | { pointerEvents: "none" } |
disableOptimization | Boolean | true |
License
MIT licensed. Copyright (c) Richard Zimerman 2017. See LICENSE.md for more details.