Show geojson
Get instances of google.maps.Map class and instance of google.maps using useMap hook.
Then using google api datalayer and api reference just add geojson using React.useEffect hook
// @flowimport * as React from 'react';import { Map, useMap } from 'rgm';import { useGoogleApiLoader } from '../dev-src/hooks';import { Ratio } from '../dev-src/controls';// https://developers.google.com/maps/documentation/javascript/reference/map#MapOptionsconst MAP_OPTIONS = {zoom: 13,center: {lat: 46.22212,lng: 6.14156,},// disable cmd-zoom and 2 fingers zoom I personally dislike itgestureHandling: 'greedy',clickableIcons: false,};const BG_STYLE = {fillColor: 'transparent',strokeColor: 'white',strokeWeight: 6,strokeOpacity: 1,cursor: 'hand',};const FG_STYLE = {fillColor: 'transparent',strokeColor: 'blue',strokeWeight: 2,strokeOpacity: 1,cursor: 'hand',};// https://developers.google.com/maps/documentation/javascript/datalayer// https://developers.google.com/maps/documentation/javascript/reference/dataconst GeoJson = ({ children }) => {const { map } = useMap();React.useEffect(() => {let style = BG_STYLE;// To prevent style blink we override style inside addListenerconst addFeatureListener = map.data.addListener('addfeature', event => {map.data.overrideStyle(event.feature, style);});const features = [];// Add background white shaped border for better visibilityfeatures.push(...map.data.addGeoJson(children));// Add foreground thinner border with primary colorstyle = FG_STYLE;features.push(...map.data.addGeoJson(children));addFeatureListener.remove();return () => {features.forEach(feature => map.data.remove(feature));};}, [map, children]);return null;};export default function GeoJSONPage() {const api = useGoogleApiLoader();return (<Ratio value={3 / 4}>{api && (<Map api={api} options={MAP_OPTIONS}><GeoJson>{geoJSON}</GeoJson></Map>)}</Ratio>);}const geoJSON = {type: 'Feature',geometry: {type: 'MultiPolygon',coordinates: [[[[6.166701, 46.224467],[6.165925, 46.222455],[6.1619, 46.215224],[6.155766, 46.217359],[6.151245, 46.216282],[6.151087, 46.215332],[6.150485, 46.215169],[6.1509, 46.214227],[6.150811, 46.214036],[6.14938, 46.214312],[6.149151, 46.214004],[6.1494, 46.213891],[6.148978, 46.213333],[6.149199, 46.213245],[6.149111, 46.213092],[6.148458, 46.213299],[6.148611, 46.213478],[6.148046, 46.213725],[6.14791, 46.213552],[6.146289, 46.214207],[6.146402, 46.214354],[6.146021, 46.214516],[6.145856, 46.214388],[6.145229, 46.214795],[6.145365, 46.214889],[6.144523, 46.215537],[6.140424, 46.215467],[6.140431, 46.214992],[6.140001, 46.214473],[6.140495, 46.21431],[6.140344, 46.213461],[6.139154, 46.211822],[6.138298, 46.212118],[6.137611, 46.212103],[6.137077, 46.212714],[6.136788, 46.212579],[6.136173, 46.21166],[6.136793, 46.21125],[6.136433, 46.210877],[6.135918, 46.210767],[6.136631, 46.210466],[6.136455, 46.210278],[6.135874, 46.210503],[6.135143, 46.210281],[6.135855, 46.209982],[6.135933, 46.208969],[6.135134, 46.20892],[6.135138, 46.20837],[6.1349, 46.208432],[6.134884, 46.208718],[6.133399, 46.209087],[6.133291, 46.20889],[6.132011, 46.209076],[6.131403, 46.209387],[6.131373, 46.209693],[6.130356, 46.210561],[6.129696, 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