qr.js

/*export default class App extends Component {
 state = ....
 
render() {
    return (
        /*{
      <View style={{flex:1}}>
        this.state.webview && (<WebView 
            source={{uri: this.state.url}}
            style={{flex:1}}
            scalesPageToFit={true} />
            )}
      

            {!this.state.webview && (<QRCodeScanner
        onRead={this.onSuccess.bind(this)}
        reactivate={true}
        reactivateTimeout={4000}/>
         
          )}*/
        <TouchableOpacity
            style={{
              alignItems: 'center',
              justifyContent: 'center',
              backgroundColor: 'rgba(0,0,0,0.2)',
              borderRadius: 50,
              width: 75,
              height: 75,
              position: 'absolute',
              right: 5,
              bottom: 5
            }}
            onPress={() => this.setState({ webview: false })}>
            <Text style={{textAlign: 'center'}}>Click to Reload</Text>
          </TouchableOpacity>
    </View>
  )
}