react google map reference

reference:
https://www.npmjs.com/package/google-map-react
https://tomchentw.github.io/react-google-maps/#installation
https://www.react-simple-maps.io/
https://www.fullstackreact.com/articles/how-to-write-a-google-maps-react-component/




https://developers.google.com/maps/documentation/javascript/examples/icon-simple

google api key
https://console.developers.google.com

in console google developer, create project

select api service for the project

select 1 api, click create credentials, key is generated.

google not found error - add window.google

https://stackoverflow.com/questions/43714895/google-is-not-defined-in-react-app-using-create-react-app