react-map-gl-draw

react-map-gl-draw is a drawing library tailored for react-map-gl.

Getting started

Running the example

1. git clone [e-mail]:uber/nebula.gl.git
2. cd nebula.gl
3. yarn
4. cd examples/react-map-gl-draw
5. yarn
6. export MapboxAccessToken='<Add your key>'
7. yarn start-local
8. You can view/edit geometry.

Installation

yarn add react-map-gl-draw

Options

• mode (String, Optional)

  • EditorModes.READ_ONLY - Not interactive. This is the default mode.
  • EditorModes.SELECT_FEATURE - Lets you select, delete, and drag features.
  • EditorModes.EDIT_VERTEX - Lets you select, delete, and drag vertices; and drag features.
  • EditorModes.DRAW_PATH - Lets you draw a GeoJson LineString feature.
  • EditorModes.DRAW_POLYGON - Lets you draw a GeoJson Polygon feature.
  • EditorModes.DRAW_POINT - Lets you draw a GeoJson Point feature.
  • EditorModes.DRAW_RECTANGLE - Lets you draw a Rectangle (represented as GeoJson Polygon feature).

• selectedFeatureId (String, Optional) - id of the selected feature. EditorModes assigns a unique id to each feature which is stored in feature.properties.id.

• clickRadius (Number, optional) - Radius to detect features around a hovered or clicked point. Default value is 0

• onSelect (Function, Required) - callback when a feature is selected. Receives an object containing selectedFeatureId.

• onUpdate (Function, Required) - callback when anything is updated. Receives one argument features that is the updated list of GeoJSON features.

Feature object structure: react-map-gl-draw is stateful component.

{
  id, // an unique identified generated inside react-map-gl-draw library 
  geometry: {
    coordinates, // latitude longitude pairs of the geometry points
    type // geojson type, one of `Point`, `LineString`, or `Polygon`
  },
  properties: {
    renderType, // Mainly used for styling, one of `Point`, `LineString`, `Polygon`, or `Rectangle`. Different from `geometry.type`. i.e. a rectangle's renderType is `Rectangle`, and `geometry.type` is `Polygon`. An incomplete (not closed) Polygon's renderType is `Polygon`, `geometry.type` is `LineString`
    ...otherProps // other properties user passed in
  }
}

Styling related Options

• getFeatureStyle (Function, Optional) : Object - A function to style a feature, function parameters are
  • feature: feature to style .
  • state: one of SELECTED, HOVERED, INACTIVE, UNCOMMITTED.

Returns is a map of style objects passed to SVG path elements.

• getEditHandleStyle (Function, Optional) : Object - A function to style an `editHandle, function parameters are
  • feature: feature to style.
  • index: index of the editHandle vertex in the feature.
  • state: one of SELECTED, HOVERED, INACTIVE, UNCOMMITTED.

Returns is a map of style objects passed to SVG circle or rect elements.

• getEditHandleShape (String|Function, Optional): if is a string, should be one of rect or circle. If is a function, will receive the following parameters
  • feature: feature to style.
  • index: index of the editHandle vertex in the feature.
  • state: one of SELECTED, HOVERED, INACTIVE, UNCOMMITTED.

Explanations

• Feature: any drawn shape, one of point, line, polygon or rectangle.
• EditHandle: vertex of the feature being edited.

State related concepts:

• INACTIVE: neither selected nor hovered, default state of a complete feature or editHandle.
• SELECTED: being clicked or dragged.
• HOVERED: hovered over by the mouse pointer.
• UNCOMMITTED: in the middle of drawing, not yet added to the feature being edited.

Styling based on state:

As shown in the above image, for the feature currently being edited,

• getFeatureStyle({feature, state: SELECTED}) will be applied to the committed parts of the feature. (Green strokes)
• getEditHandleStyle({state: SELECTED}) will be applied to the committed editHandle vertices. (Vertices with black stroke)
• getFeatureStyle({feature, state: UNCOMMITTED}) will be applied to the uncommitted parts of the feature. (Gray stroke)
• getEditHandleStyle({state: UNCOMMITTED}) will be applied to the uncommitted editHandle vertex. (Gray vertex)

Code Example

import React, { Component } from 'react';
import MapGL, {_MapContext as MapContext} from 'react-map-gl';
import MapGLDraw, { EditorModes } from 'react-map-gl-draw';

const MODES = [
  { id: EditorModes.EDIT_VERTEX, text: 'Select and Edit Feature'},
  { id: EditorModes.DRAW_POINT, text: 'Draw Point'},
  { id: EditorModes.DRAW_PATH, text: 'Draw Polyline'},
  { id: EditorModes.DRAW_POLYGON, text: 'Draw Polygon'},
  { id: EditorModes.DRAW_RECTANGLE, text: 'Draw Rectangle'}
];

class App extends Component {
  constructor(props) {
    super(props);
    this.state = {
      viewport: {
        width: 800,
        height: 600,
        longitude: -122.45,
        latitude: 37.78,
        zoom: 14
      },
      selectedMode: EditorModes.READ_ONLY,
      features: [],
      selectedFeatureId: null
    };
  }
  
  componentDidMount() {
    // add features
    const initialFeatures = [{...}];
    this._mapRef.add(initialFeatures);
  }
  
  _updateViewport = (viewport) => {
    this.setState({viewport});
  }
  
  _onSelect = ({ selectedFeatureId }) => {
    this.setState({ selectedFeatureId });
  };
  
  _onUpdate = features => {
    this.setState({
      features
    });
  };

  _switchMode = evt => {
    const selectedMode = evt.target.id === this.state.selectedMode ? EditorModes.READ_ONLY : evt.target.id;
    this.setState({
      selectedMode,
      selectedFeatureId: null
    });
  };
  
  _renderControlPanel = () => {
    return (
      <div style={{position: absolute, top: 0, right: 0, maxWidth: '320px'}}>
        <select onChange={this._switchMode}>
          <option value="">--Please choose a mode--</option>
          {MODES.map(mode => <option value={mode.id}>{mode.text}</option>)}
        </select>
      </div>
    );
  }
  
  _getEditHandleStyle = ({feature, featureState, vertexIndex, vertexState}) => {
    return {
      fill: vertexState === `SELECTED` ? '#000' : '#aaa',
      stroke: vertexState === `SELECTED` ? '#000' : 'none'
    }
  }
  
  _getFeatureStyle = ({feature, featureState}) => {
    return {
      stroke: featureState === `SELECTED` ? '#000' : 'none',
      fill: featureState === `SELECTED` ? '#080' : 'none',
      fillOpacity: 0.8
    }
  }

  render() {
    const { viewport, selectedMode, selectedFeatureId, features } = this.state;
    return (
      <MapGL
        {...viewport}
        width="100%"
        height="100%"
        mapStyle="mapbox://styles/uberdata/cive48w2e001a2imn5mcu2vrs"
        onViewportChange={this._updateViewport}
      >
        <MapGLDraw
          ref={_ => this._drawRef = _}
          mode={selectedMode}
          features={features}
          selectedFeatureId={selectedFeatureId}
          onSelect={this._onSelect}
          onUpdate={this._onUpdate}
          getEditHandleStyle={this._getEditHandleStyle}
          getFeatureStyle={this._getFeatureStyle}
        />
        {this._renderControlPanel()}
      </MapGL>
    );
  }
}