I am very new to programming with React-native, and I was wondering if anyone could explain how I should fix this error? I was following along with a tutorial and had an error come up due to this section of code, even though it matched the tutorial code.
Here is the section of code:
import React, { createContext, useContext } from "react";
import * as Google from "expo-google-app-auth";
const AuthContext = createContext({});
export const AuthProvider = ({ children }) => {
const signInWithGoogle = async() => {
await Google.logInAsync
}
return (
<AuthContext.Provider
value={{
user: null,
}}
>
{children}
</AuthContext.Provider>
);
};
export default function useAuth() {
return useContext(AuthContext);
}
These other two sections may be relevant as well:
Root of the App:
import React from 'react';
import { Text, View, SafeAreaView, Button, Alert } from 'react-native';
import AuthProvider from "./hooks/useAuth";
import StackNavigator from "./StackNavigator";
import { NavigationContainer} from "#react-navigation/native";
// Function for creating button
export default function App() {
return (
<NavigationContainer>
<AuthProvider>
<StackNavigator />
</AuthProvider>
</NavigationContainer>
);
}
This is my code for the Login Screen:
import React from 'react';
import { View, Text } from 'react-native';
import useAuth from '../hooks/useAuth';
const LoginScreen = () => {
const { user } = useAuth();
console.log(user);
return (
<View>
<Text>
Login to the app
</Text>
</View>
);
};
export default LoginScreen
This is the error that appears:
Error: Objects are not valid as a React child (found: object with keys {}). If you meant to render a collection of children, use an array instead.
I suggest you auth with firebase. it makes easier this things.
Related
I am using react-navigation module to implement the bottom tab bar, and now I want to pass the parameters to page B during the operation in page A without page jumping, is there any way to achieve this?
I read the official documentation of react-navigation, and it seems that only the navigation.navigation method can pass parameters across pages, but this will cause page jumps
You can use the AsyncStorage package. Save the data you will use on PageB with a key on PageA. Then get saved data on the PageB.
import React, { useEffect } from 'react';
import { Button } from 'react-native';
import AsyncStorage from '#react-native-async-storage/async-storage';
export default PageA = ({ navigation }) => {
useEffect(() => {
AsyncStorage.setItem("PageParams", "something")
}, [])
return (
<Button title='Navigate' onPress={() => navigation.navigate("PageB")} />
);
};
import { View } from 'react-native';
import React, { useEffect } from 'react';
import AsyncStorage from '#react-native-async-storage/async-storage';
export default PageB = () => {
useEffect(async () => {
const params = await AsyncStorage.getItem("PageParams")
console.log(params) // output: something
})
return (
<View />
);
};
import React, {Component} from 'react'
import { StackNavigator } from 'react-navigation'
import {connect} from 'react-redux'
import {getAllUsers} from '../actions'
import {List, ListItem} from 'react-native-elements'
import { StyleSheet, Text, View, FlatList } from 'react-native'
const UserDetail = () => {
<View>
<Text>User Detail</Text>
</View>
}
const Home = ({ navigation }) => (
<List>
{typeof users === 'string' &&
<FlatList
data={users}
/>
}
</List>
)
const Stack = StackNavigator({
Home: {
screen: Home
},
UserDetail: {
screen: UserDetail
}
})
class MainScreen extends Component {
componentDidMount(){
this.setState({ users : this.props.getAllUsers() })
}
render() {
const users = typeof this.props.decks === 'string'
? Object.values(JSON.parse(this.props.users)) : ''
return(
<Stack />
)
}
}
function mapStateToProps(users) {
return {
users: users,
}
}
function mapDispatchToProps(dispatch) {
return {
getAllUsers: () => dispatch(getAllUsers()),
}
}
export default connect(
mapStateToProps,
mapDispatchToProps
)(MainScreen)
I have two questions:
1) I want to pass the users props from MainScreen component to Home component and later on also to UserDetail component. But I could not see any example on that on React Navigation documentation except for ScreenProps.
2) If I go to UserDetail and let's say it would be a separate component. And let's say it would call another component. How could it go back to Home for example?
I'm using Redux by the way also here and there are some who suggest to do it in Redux but still I could not make it work also. I am fairly new to React Native or React for that matter, but I could not find a definitive answer so far on this above questions.
I'm using React Router for a React Native app. Not sure what I'm missing here but I install react-router-native and require the history package, and setup a couple methods that just push a new route onto the stack but nothing happens. I console.log('clicked'); to check that it's firing and it is so not sure what's wrong.
import React, { Component } from 'react';
import { View } from 'react-native';
import Splash from './Splash';
import createHistory from 'history/createMemoryHistory';
const history = createHistory();
class SplashContainer extends Component {
goToLogin = () => {
history.push('/Login');
}
goToRegister = () => {
history.push('/SignUp');
}
render () {
console.log(history)
return (
<Splash
goToLogin={this.goToLogin}
goToRegister={this.goToRegister}
/>
);
}
}
export default SplashContainer;
import React from 'react';
import { StyleSheet, View, Text } from 'react-native';
import { Button } from 'native-base';
import { Link } from 'react-router-native';
import PropTypes from 'prop-types';
const Splash = (props) => {
console.log(props)
return (
<View style={styles.container}>
<Button light block onPress={props.goToLogin}>
<Text>Login</Text>
</Button>
<Button dark block bordered style={{marginTop: 10}} onPress={props.goToRegister}>
<Text>Register</Text>
</Button>
</View>
);
}
Splash.propTypes = {
goToLogin: PropTypes.func.isRequired,
goToRegister: PropTypes.func.isRequired
}
export default Splash;
I don't know your Router config, but your methods should be:
goToLogin = () => {
const { history } = this.props
history.push('/Login');
}
history will passed down via props of component inside Router's stack.
I'm playing with react-native / redux and am dispatching an action that is supposed to display a number yet an error gets thrown:
Unhandled JS Exception: Objects are not valid as a React child (found:
object with keys {type, payload}). If you meant to render a collection
of children, use an array instead or wrap the object using
createFragment(object) from the React add-ons. Check the render method
of Text.
createStore.js
import { createStore, applyMiddleware, combineReducers } from 'redux';
import createLogger from 'redux-logger';
import numReducer from './reducers/numReducer';
const logger = createLogger();
export default (initialState = {}) => (
createStore(
combineReducers({
numbers: numReducer
}),
initialState,
applyMiddleware(logger)
)
);
App.js
import React from 'react';
import { Provider } from 'react-redux';
import HomeScreen from './components/HomeScreen';
import createStore from './createStore';
const store = createStore();
export default () => (
<Provider store={store}>
<HomeScreen />
</Provider>
);
numReducer.js
import { LIST_NUMBERS, PICK_NUMBER } from '../actions/actionTypes';
export default (state = [], action = {}) => {
switch (action.type) {
case LIST_NUMBERS:
return action.payload || [];
case PICK_NUMBER:
return action.payload;
default:
return state;
}
};
HomeScreen.js
import React from 'react';
import { View } from 'react-native';
import NavContainer from '../containers/NavContainer';
const HomeScreen = () => (
<View>
<NavContainer />
</View>
);
export default HomeScreen;
NavContainer.js
import { bindActionCreators } from 'redux';
import { connect } from 'react-redux';
import { listNumbers, pickNumber } from '../actions/numberActions';
import Nav from '../components/Nav';
const mapStateToProps = state => ({
numbers: state.numbers
});
const mapDispatchToProps = dispatch => (
bindActionCreators({
listNumbers,
pickNumber
}, dispatch)
);
export default connect(
mapStateToProps,
mapDispatchToProps
)(Nav);
Nav.js
import React, { Component, PropTypes } from 'react';
import { View, Text } from 'react-native';
export default class Nav extends Component {
render() {
return (
<View>
<Text>FirstLine</Text>
<Text>SecondLind</Text>
<Text>Number: {this.props.pickNumber(3)}</Text>
</View>
);
}
}
Please advise what I am doing wrong. Thank you
You need to dispatch your action from inside one of your lifecycle methods or on some handler, and then use the (updated) props from your redux store in your component.
Example:
import React, { Component, PropTypes } from 'react';
import { View, Text } from 'react-native';
export default class Nav extends Component {
componentDidMount() {
this.props.pickNumber(3);
}
render() {
return (
<View>
<Text>FirstLine</Text>
<Text>SecondLind</Text>
<Text>Number: {this.props.numbers}</Text>
</View>
);
}
}
I'm using the new react-navigation library for a React Native application I'm building. I'm having an issue with passing down my ActionCreators from my Nav component down to its scenes.
I have an AppContainer that wraps the entire application.
import React, { Component } from 'react';
import { DrawerNavigator, addNavigationHelpers } from 'react-navigation';
import { connect } from 'react-redux';
import { bindActionCreators } from 'redux';
import { ActionCreators } from '../actions';
import DashboardContainer from './DashboardContainer';
import CustomersContainer from './CustomersContainer';
const ApplicationNavigation = DrawerNavigator({
Dashboard: { screen: DashboardContainer },
Customers: { screen: CustomersContainer },
});
class AppContainer extends Component {
render() {
return (
<ApplicationNavigation />
);
}
}
function mapDispatchToProps(dispatch) {
return bindActionCreators(ActionCreators, dispatch);
}
export default connect(() => { return {} }, mapDispatchToProps)(AppContainer);
Here is the CustomerContainer:
import React, {Component} from 'react';
import {View, Text, Button} from 'react-native';
export default class CustomerContainer extends Component {
btnPressed() {
this.props.listCustomers()
}
render () {
return (
<View style={{marginTop: 40}}><Text>Customer</Text>
<Button onPress={() => this.btnPressed()} title="Press Me!" />
</View>
);
}
}
Now I'm trying to call an action within my CustomerContainer this.props.listCustomers(). The problem is the ActionCreator props aren't being passed down to the screens. I've tried doing adding the screenProps prop to the ApplicationNavigation component:
But for some reason when I do this my app doesn't display any screens its just blank with no errors.
UPDATE
So I updated my CustomerContainer file:
import React, {Component} from 'react';
import {View, Text, Button} from 'react-native';
import { connect } from 'react-redux';
import { bindActionCreators } from 'redux';
import { ActionCreators } from '../actions';
class CustomerContainer extends Component {
btnPressed() {
console.log(this.props.listCompanyCustomers())
}
render () {
return (
<View style={{marginTop: 40}}><Text>Customer</Text>
<Button onPress={() => this.btnPressed()} title="Press Me!" />
</View>
);
}
}
function mapStateToProps(state) {
return {
companyCustomers: state.companyCustomers
};
}
function mapDispatchToProps(dispatch) {
return bindActionCreators(ActionCreators, dispatch);
}
export default connect(mapStateToProps, mapDispatchToProps)(CustomerContainer);
This now works; however this feels like the incorrect way to go about this.
What redux connect basically does is:
Wrap your component
Declare contextProps to get access to dispatch
pass the dispatch to your component props.
If you pass the connect mapDispatchToProps, then it creates the mapping of the methods to dispatch.
So if you connect you AppContainer, its children won't get these dispatch methods, unless AppContainer passes them to its children (but this what connect comes to prevent).
So to sum up, you should connect any component that needs to use dispatch, otherwise it won't get it.
If you don't want to copy paste the mapDispatchToProps, you can just delete it and use this.props.dispatch instead:
import { ActionCreators } from '../actions';
class CustomerContainer extends Component {
btnPressed() {
this.props.dispatch(ActionCreators.listCompanyCustomers());
}
render () {
return (
<View style={{marginTop: 40}}><Text>Customer</Text>
<Button onPress={() => this.btnPressed()} title="Press Me!" />
</View>
);
}
}