geolocation in React, use react-google-maps - reactjs

Question

How to change defaultCenter in react-google-maps ?
I need to find my geolocation and change default values lat and lng.
import React from "react";
import { withScriptjs, withGoogleMap, GoogleMap, Marker } from "react-google-maps";
const getLocation = () =>{
const pos = {};
const geolocation = navigator.geolocation;
if (geolocation) {
geolocation.getCurrentPosition(findLocal, showEror);
}
function findLocal(position){
pos.lat = position.coords.latitude;
pos.lng = position.coords.longitude;
}
function showEror(){console.log(Error)}
return pos;
};
const myLocation = getLocation(); // object has lat and lng
I need to transfer my data to the component MapWithAMarker next: Сenter={myLocation} and Marker position={myLocation}
class GoogleMapCenter extends React.Component{
render(){
const MapWithAMarker = withScriptjs(withGoogleMap(props =>
<GoogleMap
defaultZoom={10}
defaultCenter={{ lat: -34.397, lng: 150.644 }}>
{props.isMarkerShown && <Marker position={{ lat: -34.397, lng: 150.644 }} />}
</GoogleMap>
));
return(
<MapWithAMarker
isMarkerShown
googleMapURL="https://maps.googleapis.com/maps/api/js?key=AIzaSyC4R6AN7SmujjPUIGKdyao2Kqitzr1kiRg&v=3.exp"
loadingElement={<div style={{ height: `100%` }} />}
containerElement={<div style={{ height: `400px` }} />}
mapElement={<div style={{ height: `100%` }} />}
/>
)
}
}
export default GoogleMapCenter;
If I use this.props, it does not work.
<MapWithAMarker
center={this.props.myLocation}
position={this.props.myLocation}
isMarkerShown
googleMapURL="https://maps.googleapis.com/maps/api/js?key=AIzaSyC4R6AN7SmujjPUIGKdyao2Kqitzr1kiRg&v=3.exp"
loadingElement={<div style={{ height: `100%` }} />}
containerElement={<div style={{ height: `400px` }} />}
mapElement={<div style={{ height: `100%` }} />}
/>
or
<GoogleMap
defaultZoom={10}
defaultCenter={this.props.myLocation}>
{props.isMarkerShown && <Marker position={this.props.myLocation} />}
</GoogleMap>

Answer 1

Default properties like defaultCenter could only be set as initial state, center property could be used instead to re-render (center) the map.
The following example demonstrates how to center the map based on current location
class App extends React.Component {
constructor(props) {
super(props)
this.state = {
currentLatLng: {
lat: 0,
lng: 0
},
isMarkerShown: false
}
}
showCurrentLocation = () => {
if (navigator.geolocation) {
navigator.geolocation.getCurrentPosition(
position => {
this.setState(prevState => ({
currentLatLng: {
...prevState.currentLatLng,
lat: position.coords.latitude,
lng: position.coords.longitude
},
isMarkerShown: true
}))
}
)
} else {
error => console.log(error)
}
}
componentDidMount() {
this.showCurrentLocation()
}
render() {
return (
<div>
<MapWithAMarker
isMarkerShown={this.state.isMarkerShown}
currentLocation={this.state.currentLatLng} />
</div>
);
}
}
where
const MapWithAMarker = compose(
withProps({
googleMapURL: "https://maps.googleapis.com/maps/api/js",
loadingElement: <div style={{ height: `100%` }} />,
containerElement: <div style={{ height: `400px` }} />,
mapElement: <div style={{ height: `100%` }} />,
}),
withScriptjs,
withGoogleMap
)((props) =>
<GoogleMap
defaultZoom={8}
center={{ lat: props.currentLocation.lat, lng: props.currentLocation.lng }}
>
{props.isMarkerShown && <Marker position={{ lat: props.currentLocation.lat, lng: props.currentLocation.lng }} onClick={props.onMarkerClick} />}
</GoogleMap>
)
Demo (edit)