react-gmail-scanner

import ReactGmailScanner, { ButtonScan } from 'react-gmail-scanner';
 
...
 
componentDidMount(){
    ReactGmailScanner.init('https://test.com/verify');
    ReactGmailScanner.setBackgroundColor({
        backgroundColor:'#21CE99',
        color: '#fff'
    });
}
 
// triggering it manually
handleOnPress(){
    ReactGmailScanner.scan();
}
 
// triggering it automatically
render(){
    return (<ButtonScan />);
}