So I'm trying to figure out the best way to display a Toast error and success function when the API call fires from redux.
My line of thinking: Create action for the API call. If successful, then I want the screen to change to the home screen. If it fails, then display the message in a Toast.
Here's what some of my actions look like:
export function getTokenAPI(username, password) {
return async function action(dispatch) {
try {
dispatch({ type: t.AUTH_GET_TOKEN });
dispatch(setLoading(true));
const { data } = await API.authGetToken(username, password);
const { success } = data;
if (success) {
const { access_token, refresh_token } = data;
dispatch(setAccessToken(access_token));
dispatch(setRefreshToken(refresh_token));
await dispatch(setLoading(false));
} else if (!success) {
const { errorMessage } = data;
throw Error(errorMessage);
}
} catch (e) {
dispatch(setError(e.message));
dispatch(setLoading(false));
}
};
}
The setError action sets the error key to true and sets the errorMessage. Here's what my screen looks like:
import React from 'react';
import { Container, View, Toast } from 'native-base';
import styles from './styles';
import { connect } from 'react-redux';
import { authActions } from '_ducks/auth';
const LoginScreen = props => {
const { getToken, navigation } = props;
const { navigate } = navigation;
const navigateToHome = () => navigate('Home');
const handleLogin = async () => {
const { error, errorMessage } = props;
await getToken('sample', 'pass123');
if (error) {
Toast.show({
text: errorMessage,
buttonText: 'kay',
});
} else {
navigateToHome();
}
};
return (
<Container>
<View style={styles.container}>
<LoginButton onPress={handleLogin} />
</View>
</Container>
);
};
const mapDispatchToProps = dispatch => ({
getToken: () => dispatch(authActions.getTokenAPI()),
});
const mapStateToProps = state => ({
isLoading: state.authReducer.isLoading,
error: state.authReducer.error,
errorMessage: state.authReducer.errorMessage,
});
export default connect(
mapStateToProps,
mapDispatchToProps,
)(LoginScreen);
So if there's an error, then display the toast. If it's successful, navigate to the home screen. Essentially, error will not be true quick enough to make the check within handleLogin work appropriately.
Any recommendations on the pattern or process? Should I be using a useEffect hook here?
Related
I have the following React Native modules:
_localStorage.js
import AsyncStorage from '#react-native-community/async-storage';
const _storeData = async (key, value) => {
try {
await AsyncStorage.setItem(key, value);
} catch (error) {
console.log(error);
}
}
const _retrieveData = async (key) => {
try {
await AsyncStorage.getItem(key);
} catch (error) {
console.log(error);
}
}
export {_storeData, _retrieveData};
AppHeader.js
import React from 'react';
import {Button} from 'react-native-paper';
import {_retrieveData, _storeData} from '../../utils/_localStorage'
const LoginButton = () => {
return (
<Button icon='login' color='yellow' onPress={() => navigation.navigate('Login')}>
Login
</Button>
)
}
const UserButton = (user) => {
return (
<Button color='yellow' onPress={() => console.log('Botón usuario presionado...')}>
text
</Button>
)
}
const AppHeader = ({navigation, route}) => {
const user = _retrieveData('user');
console.log(user);
return user === ''? <LoginButton />: <UserButton user={user} />;
}
export default AppHeader;
I expect _retrieveData() to return the value of the key parameter, or null if it doesn't exits, but what I am getting in the console is this: {"_U": 0, "_V": 0, "_W": null, "_X": null}.
This is not how documentation of AsyncStorage indicates it works.
It's because you're not waiting for _retrieveData to finish. You're just setting user to the async function instead of waiting for its returned value.
Try something like this:
const AppHeader = ({navigation, route}) => {
const [user, setUser] = useState();
const [isLoading, setIsLoading] = useState(false);
useEffect(() => {
fetchUser();
}, [])
const fetchUser = async () => {
setIsLoading(true);
const userData = await _retrieveData('user');
setUser(userData);
setIsLoading(false);
}
if (isLoading) return <LoadingIndicator />
if (!!user) return <UserButton user={user} />
return <LoginButton />;
}
I've called fetchUser in the initial useEffect that gets called when the AppHeader component is first loaded. It sets a loading boolean to true and then requests the user data. When the userData is returned it sets it in state and sets loading to false.
You don't need the loading bit but I included it otherwise your app would show the login button while it's fetching the data. You'll have to create the LoadingIndicator component yourself.
_retrieveData is returning promise here. You need to await for that promise to resolve. Try writing it like this:
const _retrieveData = async (key) => {
try {
const data = await AsyncStorage.getItem(key);
return data;
} catch (error) {
console.log(error);
}
}
AppHeader.js
const AppHeader = ({navigation, route}) => {
_retrieveData('user').then((user)=>{
console.log(user);
return user === ''? <LoginButton />: <UserButton user={user} />;
});
}
Read this for more clarity : https://developer.mozilla.org/en-US/docs/Learn/JavaScript/Asynchronous/Async_await
You're not returning anything from your _retrieveData function. Try writing it like so:
const _retrieveData = async (key) => {
try {
const data = await AsyncStorage.getItem(key);
return data;
} catch (error) {
console.log(error);
}
}
I have been for several hours trying to get an API to be called in ReactNative useEffect hook. Sometimes when I restart my app the value is resolved. But most of the time, I have an Unhandled promise rejection. I googled and tried various methods. I tried using .then etc.. I just can't figure it out.
import React, { useState, useContext, useEffect } from 'react';
import { View, Text, StyleSheet, TouchableOpacity, FlatList } from 'react-native';
import { EvilIcons } from '#expo/vector-icons';
import jsonServer from '../api/jsonServer';
const ShowScreen = ({ navigation }) => {
const id = navigation.getParam('id');
const [post, setPost] = useState([]);
const getBlog = async () => {
const result = await jsonServer.get(`http://0.0.0.0/blog/docroot/jsonapi/node/article/${id}`);
return result;
}
useEffect(() => {
async function setToState() {
const val = await getBlog();
setPost(val);
}
setToState();
},[]);
return (
<View>
<Text>Here { console.log(post) }</Text>
</View>
);
};
ShowScreen.navigationOptions = ({ navigation }) => {
return {
headerRight: (
<TouchableOpacity
onPress={() =>
navigation.navigate('Edit', { id: navigation.getParam('id')
})}
>
<EvilIcons name="pencil" size={35} />
</TouchableOpacity>
)
};
};
const styles = StyleSheet.create({});
export default ShowScreen;
What you could do is something like this:
....
....
const [post, setPost] = useState([]);
const [isMounted, setIsMounted] = useState(false);
const getBlog = async () => {
const result = await jsonServer.get(`http://0.0.0.0/blog/docroot/jsonapi/node/article/${id}`);
return result;
}
useEffect(() => {
setIsMounted(true)
async function setToState() {
// using try catch I'm handling any type of rejection from promises. All errors will move to catch block.
try{
const val = await getBlog();
// checking if component is still mounted. If mounted then setting a value. We shouldn't update state on an unmounted component.
if(isMounted){
setPost(val);
}
} catch(err){
console.log("Error", err)
}
}
setToState();
return () => {
// Setting is mounted to false as the component is unmounted.
setIsMounted(false)
}
},[]);
I believe this will solve your Unhandled promise rejection error. Please try if it still doesn't solve the issue will create the same in Sanck.
I think my issue was not just promise, the issue is also seems to be me not handling undefined/null in the state. The below code is working for me.
import React, { useState, useContext, useEffect } from 'react';
import { View, Text, StyleSheet, TouchableOpacity, FlatList } from 'react-native';
import { EvilIcons } from '#expo/vector-icons';
import jsonServer from '../api/jsonServer';
const ShowScreen = ({ navigation }) => {
const id = navigation.getParam('id');
const [post, setPost] = useState([]);
const getBlog = async () => {
const result = await jsonServer.get(`http://hello.com/jsonapi/node/article/${id}`).then(
res => {
setPost(res)
return res;
}, err => {
console.log(err);
});
}
useEffect(() => {
setPost(getBlog());
},[]);
return (
<View>
<Text>{ post.data ? post.data.data.id : "" }</Text>
</View>
);
};
export default ShowScreen;
Note: I am setting the state in useEffect as well as in the request. I am yet to check if I can just do it once.
I am new to React Native and trying to build an App with login function. Here is the overview of my App.
In my root app.js
const rootReducer = combineReducers({
login: loginReducer,
preload: preloadReducer,
});
const store = createStore(rootReducer, applyMiddleware(ReduxThunk));
export default function App() {
return (
<Provider store={store}>
<MyNavigator/>
</Provider>
);
};
In my LoginScreen.js, I have
import * as authActions from '../store/actions/auth';
const LoginScreen = props => {
const loginHandler = async () => {
try {
// login here
await dispatch(authActions.login(username, password));
// I want to get login result and navigate to different screens
if (alreadyLogin) {
props.navigation.navigate('MainScreen');
} else {
props.navigation.navigate('StartupScreen');
}
}
catch (err) {
console.log(err);
}
}
return (<View style={styles.login}>
<Button title='Login' onPress={loginHandler}
</View>);
}
In the ../store/action/auth.js
export const login = (username, password) ={
return async dispatch => {
const response = await fetch(url);
const resData = await response.json();
let results = JSON.parse(resData.results);
// if login success, I dispatch the token for later use
if (resData.errno===0){
dispatch({ type: LOGIN , result: results });
} else {
dispatch({ type: RESET , result: null });
}
}
}
Can I achieve what I want with current structure? I want to get login result and navigate to different screens in my LoginScreen.js above. Thank you.
React-admin version 2 used redux-form. Together with the documentation "Altering the Form Values before Submitting" i created a custom button that returns a form error from a custom function, or does a save.
import React, { Component } from 'react';
import { connect } from 'react-redux';
import { crudCreate, SaveButton, Toolbar } from 'react-admin';
import { SubmissionError } from 'redux-form';
const myValidate = (values) => {
const errors = {};
if (values.files < 1) errors.files = 'resources.Order.errors.files';
return errors;
};
// A custom action creator which modifies the values before calling the default crudCreate action creator
const saveWithNote = (values, basePath, redirectTo) =>
crudCreate('posts', { ...values, average_note: 10 }, basePath, redirectTo);
class SaveWithNoteButtonView extends Component {
handleClick = () => {
const { basePath, handleSubmit, redirect, saveWithNote } = this.props;
return handleSubmit(values => {
return new Promise((resolve, reject) => {
const errors = myValidate(values);
if (errors) {
reject(new SubmissionError(errors))
} else {
resolve( saveWithNote(values, basePath, redirect) );
};
}
});
});
};
render() {
const { handleSubmitWithRedirect, saveWithNote, ...props } = this.props;
return (
<SaveButton
handleSubmitWithRedirect={this.handleClick}
{...props}
/>
);
}
}
const SaveWithNoteButton = connect(
undefined,
{ saveWithNote }
)(SaveWithNoteButtonView);
Now in React-admin version 3 "Altering the Form Values before Submitting" Can't I do this anymore?
This code does not work:(
import React, { useCallback } from 'react';
import ProcessIcon from '#material-ui/icons/HeadsetMic';
import { useForm, useFormState } from 'react-final-form';
import { SaveButton } from 'react-admin';
const validateProcess = (values) => {
const errors = {};
if (values.files < 1) errors.files = ['resources.Order.errors.files'];
return errors
};
const SaveWithProcessButton = ({ handleSubmitWithRedirect, ...props }) => {
const form = useForm();
const formState = useFormState();
const handleClick = useCallback(() => {
return new Promise((resolve, reject) => {
const errors = validateProcess(formState.values);
if (errors) {
reject(errors)
} else {
form.change('status', "DRAFT");
resolve( handleSubmitWithRedirect('show') );
};
});
}, [form]);
return <SaveButton {...props} handleSubmitWithRedirect={handleClick} label="ra.action.process" icon={<ProcessIcon />} />;
};
export default SaveWithProcessButton;
I manage to do this. Try my code below, I hope it will works for also for you.
const handleClick = useCallback(() => {
if (!formState.valid) {
form.submit();
return;
} else { ... your code goes here }
}, [form]);
I'am creating a simple application with authentication. To change a state using redux with react-native-navigation (v1). For example, index.js
...
import { Navigation, } from 'react-native-navigation';
import { Provider, } from 'react-redux';
import store from './src/store';
import registerScreens from './src/screens';
registerScreens(store, Provider);
class App {
constructor () {
this.auth = false;
store.subscribe(this.onStoreUpdate.bind(this));
this.start();
}
onStoreUpdate () {
const state = store.getState();
if (this.auth != state.auth) {
this.auth = state.auth;
this.start();
}
}
start () {
switch (this.auth) {
case false:
Navigation.startTabBasedApp({
tabs: [{
screen: 'navigation.AuthScreen',
}, {
screen: 'navigation.RegisterScreen',
},],
});
break;
case true:
Navigation.startSingleScreenApp({
screen: {
screen: 'navigation.MainScreen',
},
});
break;
}
}
}
const application = new App();
Store is listening an update and change an application layout if need.
AuthScreen show a simple ActivityIndicator, when server request is perform. For example, auth.js
...
import { bindActionCreators, } from 'redux';
import { connect, } from 'react-redux';
import * as actions from './../actions';
...
class AuthScreen extends Component {
constructor (props) {
super(props);
this.state = {
loading: false,
...
};
this.handlePressEnter = this.handlePressEnter.bind(this);
}
handlePressEnter () {
...
this.loadingState(true);
jsonFetch(url, {
method: 'POST',
body: JSON.stringify({...}),
}).then((value) => {
this.loadingState();
this.props.actions.auth(true);
}).catch((errors) => {
this.loadingState();
console.log('Error while auth', errors);
});
}
...
loadingState (state = false) {
this.setState({
loading: state,
});
}
render () {
return (<View>
...
<Modal visible={this.state.loading} transparent={true} animationType="none" onRequestClose={() => {}}>
<View>
<ActivityIndicator size="large" animating={this.state.loading} />
</View>
</Modal>
</View>);
}
}
function mapStateToProps (state, ownProps) {
return {};
}
function mapDispatchToProps (dispatch) {
return {
actions: bindActionCreators(actions, dispatch),
};
}
export default connect(mapStateToProps, mapDispatchToProps) (AuthScreen);
I'am starting application with iOS simulator and try to authenticate. It show me activity indicator, then indicator disappear, but layout does not change. And strange behavior, if I comment this.loadingState(true); and this.loadingState(); in auth.js layout changes with success.
Can someone explain to me, why layout does not change from auth to main when activity indicator using?
I think that you can use dispatch props for loading.
For example When you call this.props.actions.auth(true);
You can return loading reducers.
handlePressEnter () {
...
dispatch({ type:'loading', loading: true });
jsonFetch(url, {
method: 'POST',
body: JSON.stringify({...}),
}).then((value) => {
dispatch({ type:'loading', loading: false });
this.props.actions.auth(true);
}).catch((errors) => {
this.loadingState();
console.log('Error while auth', errors);
});
}
And than you can use
<ActivityIndicator size="large" animating={this.props.loading} />
But dont forget the reducers return