React Native Firebase Auth function - firebase

Question

I'm using react native crud application with using firebase real time storage. I use firebase auth functionality with email and password logging. but my firebase auth is not working. It gets more issues with firebase connection. I used this function to connect firebase.
componentWillMount() {
firebase.initializeApp({
apiKey: 'xxxxxxxxxxxxxxxxxxxxxxxx',
authDomain: 'xxxxxxxxxxxxxxxxxxxxxx',
databaseURL: 'xxxxxxxxxxxxxxxxxxxxxxxxxxxx',
projectId: 'xxxxxxxxxxxxxxxxxxxxx',
storageBucket: 'xxxxxxxxxxxxxxxxxxxxxxxx',
messagingSenderId: 'xxxxxxxxxxxxxxx'
});
}
My log in button auth functionality is looks like this one:
state = { email: '', password: '', error: '' };
onButtonPress() {
const { email, password } = this.state;
firebase.auth().signInWithEmailAndPassword(email, password)
.catch(() => {
firebase.auth().createUserWithEmailAndPassword(email, password)
.catch(() => {
this.setState({ error: 'Authenticaton Failed.' });
});
});
}
I import firebase libraries like this:
import * as firebase from 'firebase';
import 'firebase/firestore';
import 'firebase/auth';
But this configurations are not working. It shows me this error:
undefined is not a function (evaluating 'firebase.auth()')
I used to get text input values this method:
value={this.state.password}
onChangeText={password => this.setState({ password })}

Answer 1

your firebase config only exists in your componentDidMount. Try like this:
Create a file <namefile>.js wherever you want and add:
import * as firebase from 'firebase'
import 'firebase/auth';
const config = {
apiKey: "your key",
authDomain: "domain",
databaseURL: xxxx",
projectId: "xxxx",
storageBucket: "xxx",
messagingSenderId: "xxxx"
};
if (!firebase.apps.length) {
firebase.initializeApp(config);
}
const auth = firebase.auth();
export {
auth
};
import auth in your component and in your button method change your code by:
auth.signInWithEmailAndPassword
it should work and every time you need to use auth, you just need to import it