how to connect react native with gmail for login code example

Example 1: how to add oAuth google signin in react native app

import { GoogleSignin, GoogleSigninButton } from 'react-native-google-signin'; 
render() {  
  <GoogleSigninButton 
  style={{ width: 192, height: 48 }}
  size={GoogleSigninButton.Size.Wide}
  color={GoogleSigninButton.Color.Dark}
  onPress={this._signIn}
  disabled={this.state.isSigninInProgress} />
};

Example 2: google login with react native

return (
    <>
      <StatusBar barStyle="dark-content" />
      <SafeAreaView>
        <ScrollView
          contentInsetAdjustmentBehavior="automatic"
          style={styles.scrollView}>
          <Header />

          <View style={styles.body}>
            <View style={styles.sectionContainer}>
              <GoogleSigninButton
                style={{width: 192, height: 48}}
                size={GoogleSigninButton.Size.Wide}
                color={GoogleSigninButton.Color.Dark}
                onPress={this._signIn}
              />
            </View>
            <View style={styles.buttonContainer}>
              {!loggedIn && <Text>You are currently logged out</Text>}
              {loggedIn && (
                <Button
                  onPress={this.signOut}
                  title="LogOut"
                  color="red"></Button>
              )}
            </View>
          </View>
        </ScrollView>
      </SafeAreaView>
    </>
  );