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Why my app is only showing loading screen? and warn me TypeError: undefined is not an object (evaluating '_asyncStorage.AsyncStorage.getItem')

Why my app is only showing loading screen? when i am running my app than its only loading and not showing other screens and showing a WARN that
` WARN Possible Unhandled Promise Rejection (id: 0): TypeError: undefined is
i think it has problem with this code
import React, { useEffect } from 'react';
import { View, ActivityIndicator, StyleSheet} from 'react-native';
import { AsyncStorage } from '#react-native-async-storage/async-storage';
import { useDispatch } from 'react-redux';
import Colors from '../constants/Colors';
import * as authActions from '../store/actions/auth';
const StartupScreen = props => {
const dispatch = useDispatch();
useEffect(() => {
const tryLogin = async () => {
const userData = await AsyncStorage.getItem('userData');
if (!userData) {
// props.navigation.navigate('Auth');
dispatch(authActions.setDidTryAutoLogin());
return;
}
const transformedData = JSON.parse(userData);
const { token, user } = transformedData;
// props.navigation.navigate('Shop');
dispatch(authActions.authenticate(user, token));
};
tryLogin();
}, [dispatch])
return (
<View style={styles.screen}>
<ActivityIndicator size="large" color={Colors.primary} />
</View>
);
};
const styles = StyleSheet.create({
screen: {
flex: 1,
justifyContent: 'center',
alignItems: 'center'
}
});
export default StartupScreen;

According to the docs you import is wrong.
This:
import { AsyncStorage } from '#react-native-async-storage/async-storage';
should be
import AsyncStorage from '#react-native-async-storage/async-storage';
Basically, what you are trying to do with {AsyncStorage} is you are importing "part" of the exported code called AsyncStorage. That is why the error says:
_asyncStorage.AsyncStorage.getItem') (asyncStorage mentioned twice) and you need the entire object out of the package.

React Native Expo - Custom Fonts Not Loading With Font.loadAsync

I'm up to date on the latest Expo version but for some reason, I can not get a simple custom font going. Here is a fresh project I set up attempting to get a custom font installed.
import React, { useState } from 'react';
import { Text, View } from 'react-native';
import AppLoading from 'expo-app-loading';
import * as Font from 'expo-font';
const fetchFonts = () =>
Font.loadAsync({
'Inter-Black': require('./assets/fonts/Inter-Black.otf'),
});
export default (props) => {
const [dataLoaded, setDataLoaded] = useState(false);
if (!dataLoaded) {
return (
<AppLoading
startAsync={fetchFonts}
onFinish={() => setDataLoaded(true)}
onError={(err) => console.log(err)}
/>
);
}
return (
<View style={{ flex: 1, justifyContent: 'center', alignItems: 'center' }}>
<Text style={{ fontFamily: 'Inter-Black', fontSize: 40 }}>
Inter Black
</Text>
<Text style={{ fontSize: 40 }}>Platform Default</Text>
</View>
);
};
This is what I get in the console:
fontFamily "Inter-Black" is not a system font and has not been loaded through Font.loadAsync.
- If you intended to use a system font, make sure you typed the name correctly and that it is supported by your device operating system.
- If this is a custom font, be sure to load it with Font.loadAsync.
at node_modules/expo-font/build/Font.js:27:16 in processFontFamily
at [native code]:null in performSyncWorkOnRoot
at [native code]:null in dispatchAction
at App.js:19:37 in AppLoading.props.onFinish
at node_modules/expo-app-loading/build/AppLoading.js:41:12 in startLoadingAppResourcesAsync
at [native code]:null in flushedQueue
at [native code]:null in invokeCallbackAndReturnFlushedQueue

You have to await the loading fucntion
const fetchFonts = async () =>
await Font.loadAsync({
'Inter-Black': require('./assets/fonts/Inter-Black.otf'),
});
Also, instead of this, try creating a custom hook to Load fonts. Check this answer.
You can do it somenthing like this
Create a folder called hooks where your App.js is located. Then inside hooks folder create a file called useFonts.js
Inside useFonts.js write like this
import * as Font from "expo-font";
export default useFonts = async () =>
await Font.loadAsync({
'Inter-Black': require('./assets/fonts/Inter-Black.otf'),
});
Now in your App.js write like this
import * as Font from 'expo-font';
import AppLoading from 'expo-app-loading';
import React, { useState } from 'react';
import useFonts from './hooks/useFonts';
export default function App() {
const [IsReady, SetIsReady] = useState(false);
const LoadFonts = async () => {
await useFonts();
};
if (!IsReady) {
return (
<AppLoading
startAsync={LoadFonts}
onFinish={() => SetIsReady(true)}
onError={() => {}}
/>
);
}
return <View styles={styles.container}>{/* Code Here */}</View>;
}

Add font resource to project folder exp assets/fonts
create variable fonts exp customFonts
Import on App.js like this
import AppLoading from 'expo-app-loading';
import { useFonts } from 'expo-font';
let customFonts = {
'Poppins-Black': require('./assets/fonts/Poppins-Black.ttf')
};
const App = () => {
const [isLoaded] = useFonts(customFonts);
if (!isLoaded) {
return <AppLoading />;
}
return <RootApp />;
}

Call function on application load in React Native

I have a React Native application and it has tabbed layout. I need to call some function when the main screen is loaded. I tried to use componentWillMount() function, but it didn't work because my screen was defined in function and not in class. How can I create on load function?
HomeScreen.js
import React, { useState, Component } from 'react';
import { View, Text } from 'react-native';
import { getText } from '..components/getText';
export default function HomeScreen() {
const [onLoadText, setText] = useState("");
const onScreenLoad = () => {
setText(getText());
}
const componentWillMount = () => {
// Not working
onScreenLoad();
}
return (
<View style={styles.container}>
<Text>{onLoadText}</Text>
</View>
);
}
const styles = StyleSheet.create({
container: {
flex: 1,
backgroundColor: '#fff',
},
});

since you're using a stateless component, you can use the useEffect hook
useEffect(() => {
// write your code here, it's like componentWillMount
}, [])

You must add useEffect
import React, { useState, Component, useEffect } from 'react';
import { View, Text } from 'react-native';
import { getText } from '..components/getText';
export default function HomeScreen() {
const [onLoadText, setText] = useState("");
const onScreenLoad = () => {
setText(getText());
}
useEffect(() => {
// write your code here, it's like componentWillMount
onScreenLoad();
}, [])
return (
<View style={styles.container}>
<Text>{onLoadText}</Text>
</View>
);
}
const styles = StyleSheet.create({
container: {
flex: 1,
backgroundColor: '#fff',
},
});

Font is not loading on either IOS or Android

It says I can use Expo.Apploading but I have no idea about that. If someone could help it would be great. This happens in either of device I am running. Below is code for App.js
import React, {useState}from 'react';
import {Text, View } from 'react-native';
import *as Font from 'expo-font';
import {AppLoading} from 'expo';
import {enableScreens} from 'react-native-screens';
import EstesGuideNavigator from './navigation/EstesGuideNavigator';
enableScreens(); // useScreens has been changed to enableScreens - this helps screens load faster in background
const fetchFonts = () => { //fetching costum fonts for my app using Async
Font.loadAsync({
'raleway-blackItalic' : require('./assets/fonts/Raleway-BlackItalic.ttf'),
'raleway-bold' : require('./assets/fonts/Raleway-Bold.ttf'),
'raleway-regular' : require('./assets/fonts/Raleway-Regular.ttf'),
'raleway-thin' : require('./assets/fonts/Raleway-Thin.ttf')
});
};
export default function App() {
const [fontLoaded, setFontLoaded] = useState(false); //initially it's false because app hasn't been loaded
if (!fontLoaded) {
return(
<AppLoading
startAsync = {fetchFonts}
onFinish = {() => setFontLoaded(true) }
/> //if assets(fonts here) is not loaded we display loading screen and load assets for app
);
}
return <EstesGuideNavigator/>;
}
Is there any way to resolve this?

I don't know what's wrong but this is how i handle my font loading, Works perfectly
import { AppLoading } from "expo";
import { Asset } from "expo-asset";
import * as Font from "expo-font";
import React, { useState } from "react";
import { Platform, StatusBar, StyleSheet, View } from "react-native";
import { Ionicons } from "#expo/vector-icons";
import AppNavigator from "./navigation/AppNavigator";
export default function App(props) {
const [isLoadingComplete, setLoadingComplete] = useState(false);
if (!isLoadingComplete && !props.skipLoadingScreen) {
return (
<AppLoading
startAsync={loadResourcesAsync}
onError={handleLoadingError}
onFinish={() => handleFinishLoading(setLoadingComplete)}
/>
);
} else {
return (
<View style={styles.container}>
{Platform.OS === "ios" && <StatusBar barStyle="default" />}
<AppNavigator />
</View>
);
}
}
async function loadResourcesAsync() {
await Promise.all([
Asset.loadAsync([
require("./assets/images/tick.png"),
require("./assets/images/error.png")
]),
Font.loadAsync({
// This is the font that we are using for our tab bar
...Ionicons.font,
// We include SpaceMono because we use it in HomeScreen.js. Feel free to
// remove this if you are not using it in your app
"space-mono": require("./assets/fonts/SpaceMono-Regular.ttf"),
"Gilroy-Bold": require("./assets/fonts/Gilroy-Bold.otf"),
"Gilroy-Medium": require("./assets/fonts/Gilroy-Medium.otf"),
"Gilroy-Heavy": require("./assets/fonts/Gilroy-Heavy.otf")
})
]);
}
function handleLoadingError(error) {
// In this case, you might want to report the error to your error reporting
// service, for example Sentry
console.warn(error);
}
function handleFinishLoading(setLoadingComplete) {
setLoadingComplete(true);
}
const styles = StyleSheet.create({
container: {
flex: 1,
backgroundColor: "#fff"
}
});

problem with hook for react-native async function

I try to load a fontfamily, I used hook with async function but I have some errors:
function Button(props: TouchableOpacityProps & ButtonProps) {
useEffect(() => {
async function loadFont() {
await Font.loadAsync({
gotham_medium: require("../../assets/GothamMedium_1.ttf")
});
}
loadFont()
}, []);
return (
<TouchableOpacity {...props} style={styles.button}>
<Text style={styles.title}>{props.title}</Text>
</TouchableOpacity>
);
};
I imported Font from expo and useEffect from react but I have this error.
error on the device

This is what I have on my app in case it may help someone.
useEffect(() => {
const loadFonts = async () => {
await Font.loadAsync({
'pokeh': require('../../assets/fonts/pokeh.ttf'),
});
setFontReady(true);
};
loadFonts();
}, []);
And these two on the top after installing expo-font with npm
import * as Font from 'expo-font';
import { AppLoading } from 'expo';
Under this tree structure:

Your error might be generated by the wrong React version. Are you sure you're using at least Expo SDK 33?
If that's not the issue, I believe it might be easier if you load all assets earlier in the process. Expo provides an AppLoading component that takes a startAsync prop, which can be used to resolve all async promises pretty easily.
So your App.js could look like:
import { AppLoading } from 'expo';
import * as Font from 'expo-font';
import React, { useState } from 'react';
import { StyleSheet, View, Text } from 'react-native';
export default function App(props) {
const [isLoadingComplete, setLoadingComplete] = useState(false);
if (!isLoadingComplete && !props.skipLoadingScreen) {
return (
<AppLoading
startAsync={loadResourcesAsync}
onError={handleLoadingError}
onFinish={() => handleFinishLoading(setLoadingComplete)}
/>
);
} else {
return (
<View style={styles.container}>
<Text style={styles.title}>Welcome to your Expo app</Text>
</View>
);
}
}
async function loadResourcesAsync() {
await Promise.all([
Font.loadAsync({
'gotham-medium': require('./assets/GothamMedium_1.ttf')
}),
]);
}
function handleLoadingError(error) {
console.warn(error);
}
function handleFinishLoading(setLoadingComplete) {
setLoadingComplete(true);
}
const styles = StyleSheet.create({
container: {
marginTop: 60,
flex: 1,
backgroundColor: '#fff',
},
title: {
fontFamily: 'gotham-medium',
fontSize: 36
}
});
and then you have access to fontFamily: 'gotham-medium' anywhere in your app. Also you can resolve multiple promises (load other assets, etc.) within the Promise.all() call.
Let me know if that helped. Cheers!