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How to render svg file in react?

I want to upload a svg file and show preview in react, but I don't know how to convert a svg file into react component. I try to use DOMParser to parse svg-xml string to Dodument Object, but it is not working.
import { useState } from 'react';
import { Upload, Button, Card } from 'antd';
import { UploadChangeParam } from 'antd/lib/upload/interface';
import 'antd/dist/antd.css';
function App() {
const [svgs, setSvgs] = useState<Document[]>([]);
const handleChange = async ({ file }: UploadChangeParam) => {
console.log(file);
let domparser = new DOMParser();
const svg = (await file.originFileObj?.text()) ?? '';
const ele = domparser.parseFromString(svg, 'image/svg+xml');
setSvgs([...svgs, ele]);
};
return (
<div style={{ margin: 50 }}>
<Upload name="file" showUploadList={false} onChange={handleChange}>
<Button>Upload</Button>
</Upload>
{/* preview list */}
<Card style={{ marginTop: 20 }}>
{svgs.map((SVGComponent) => {
return <SVGComponent />;
})}
</Card>
</div>
);
}
export default App;

You can use following library to convert svg's. You can also add its cli commands to your package.json
https://react-svgr.com/playground/

Expo React Native, How to pick default local images or user image obtained from expo image picker

I have a form that a user can select a default local image or an image from the user's photo library
Here is an expo snack use android the images can be found in the phone menu in photos
I want to save either the default local image or user's image to the form and to redux, currently able to save default images picked to form and redux.
This is what currently works.
I have a component that gets a selected local image and returns an image path witch is a number. That local image gets saved in form and in redux. currently, the user can change the local image in the form.
ImgSelector Component:
import React, { useState } from "react";
import { List, Selector, View, SelectedImg } from "./styles";
import { FlatList } from "react-native";
import { defaultImages } from "../../data/defaultImages";
const FlatlistItem = ({ image, setImg }) => {
return (
<Selector onPress={() => setImg(image)}>
<View>
<SelectedImg source={image} />
</View>
</Selector>
);
};
const ImgSelector = ({ setImg }) => {
const [selectedId, setSelectedId] = useState(null);
const renderItem = ({ item }) => (
<FlatlistItem setImg={setImg} image={item.image} />
);
return (
<View>
<FlatList
horizontal
data={defaultImages}
renderItem={renderItem}
keyExtractor={(item, index) => index.toString()}
extraData={selectedId}
/>
</View>
);
};
export default ImgSelector;
Default local images are stored like this and the path is the index which is a number this part works fine.
export const defaultImages = [
{
id: “2”,
image: require("../assets/images/singlepane.png"),
}
]
I have an imagePicker component that asks for permissions and returns a uri string that looks like this:
file:/data/data/host.exp.exponent/cache/ExperienceData/%2540anonymous%252FExpoWcPro-a828b17b-dcd7-4a04-93ca-657c8e4e511d/ImagePicker/6106d73f-c886-457d-abe9-1f1232a0d398.jpg
My form component where images are picked and saved:
import React, { useState } from "react";
import { Image } from "react-native";
const CounterForm = ({ navigation, ...props }) => {
// This is current state for default images that works
const [imgUrl, setImgUrl] = useState(props.imgUrl || defaultImage);
const [userImgUri, setUserImgUri] = useState(null);
// This gets the local image from a componnet
const handleEditImg = (newImgUrl) => {
setImgUrl(newImgUrl);
};
// This gets image uri from expo image picker
const handelUserImg = (userUri) => {
setUserImgUri(userUri);
};
// This sends data to a redux action to save
const handleSubmit = () => {
props.onFormSubmit({
id: props.id,
imgUrl,
});
setImgUrl(defaultImage);
};
return (
<FormWrapper>
<Row>
<FormButton onPress={() => handleSubmit()}>
<StyledText title="Save" color={COLORS.appBlue} />
</FormButton>
</Row>
<TopContent>
{/* I tried this to get user image and displays in form */}
<Image
source={{ uri: userImgUri }}
style={{ width: 100, height: 100 }}
/>
{/* This current implementation gets local images
<Image
source={imgUrl}
style={{ width: 100, height: 100 }}
/> */}
{/* I tried this only gets local images
{imgUrl ? (
<Image source={imgUrl} style={{ width: 100, height: 100 }} />
) : (
<Image
source={{ uri: userImgUri }}
style={{ width: 100, height: 100 }}
/>
)} */}
</TopContent>
<Row>
<ImagePicker getUserImg={handelUserImg} />
</Row>
<View>
<ImgSelector setImg={handleEditImg} />
</View>
</FormWrapper>
);
};
export default CounterForm;

if you use the last sdk version of Expo (40) and the right package expo-image-picker you need to follow this instructions.
First you need to ask for permissions :
const { status } = await ImagePicker.requestMediaLibraryPermissionsAsync();
if (status !== 'granted') {
alert('Sorry, we need camera roll permissions to make this work!');
}
And then call method to select image from library :
let result = await ImagePicker.launchImageLibraryAsync({
mediaTypes: ImagePicker.MediaTypeOptions.All,
allowsEditing: true,
aspect: [4, 3],
quality: 1,
});
So you got image uri by accessing result.uri, you need to save this value (e.g in user store) and display it by selecting your store or default value if there is not stored value :
<View style={{ flex: 1, alignItems: 'center', justifyContent: 'center' }}>
<Button title="Pick an image from camera roll" onPress={pickImage} />
/** imgUrl = stored image uri, defaultImages[0].image = default image uri */
<Image source={imgUrl ? { uri: imgUrl } : defaultImages[0].image} />
</View>

I found the answer it's updated in expo snack
import React, { useState } from "react";
import { List, Selector, View, SelectedImg } from "./styles";
import { FlatList } from "react-native";
import { defaultImages } from "../data";
const FlatlistItem = ({ image, setImg }) => {
return (
<Selector onPress={() => setImg(image)}>
<View>
<SelectedImg source={{uri: image}} />
</View>
</Selector>
);
};
const ImgSelector = ({ setImg }) => {
const [selectedId, setSelectedId] = useState(null);
const renderItem = ({ item }) => {
return (
<FlatlistItem setImg={setImg} image={item} />
)
}
return (
<View>
<FlatList
horizontal
data={defaultImages}
renderItem={renderItem}
keyExtractor={(item, index) => index.toString()}
extraData={selectedId}
/>
</View>
);
};
export default ImgSelector;
Form
import React, { useState } from "react";
import {Asset} from 'expo-asset';
import StyledText from "../UiComponents/StyledText";
import { TouchableWithoutFeedback, Keyboard } from "react-native";
import {
FormWrapper,
TextInputWrapper,
TopContent,
NumberWrapper,
Row,
FormButton,
View,
} from "./styles";
import StyledInput from "../UiComponents/StyledInput";
const defaultImage = Asset.fromModule(require('../assets/komloy.jpg')).uri
import WindowSelector from "../ImgSelector";
import StyledButton from "../UiComponents/StyledButton";
import ImagePicker from "../components/imagePicker";
import { Image } from "react-native";
const DismissKeyboard = ({ children }) => (
<TouchableWithoutFeedback onPress={() => Keyboard.dismiss()}>
{children}
</TouchableWithoutFeedback>
);
const CounterForm = ({ navigation, ...props }) => {
const [imgUrl, setImgUrl] = useState(props.imgUrl || defaultImage);
const handleEditImg = (newImgUrl) => {
setImgUrl(newImgUrl);
};
const handelUserImg = (userUri) => {
setImgUrl(userUri);
};
const handleSubmit = () => {
props.onFormSubmit({
id: props.id,
imgUrl
});
setImgUrl(defaultImage);
};
return (
<DismissKeyboard>
<FormWrapper>
<TopContent>
<Image
source={{uri: imgUrl}}
style={{ width: 100, height: 100 }}
/>
</TopContent>
<Row>
<StyledText title="Select a image" />
<ImagePicker getUserImg={handelUserImg} />
</Row>
<View>
<WindowSelector setImg={handleEditImg} />
</View>
</FormWrapper>
</DismissKeyboard>
);
};
export default CounterForm;
Data
import {Asset} from 'expo-asset';
const imageURI = Asset.fromModule(require('./assets/islands.jpg')).uri
const imageURI2 = Asset.fromModule(require('./assets/maeYai.jpg')).uri
export const defaultImages = [
imageURI, imageURI2
]

I am trying to run this react native screen where it fetches data for me. This gets run when i click the text from a home screen. But it's not working

This is where my home screen is:
import React, { useState } from "react";
import {
StyleSheet,
View,
Text,
Button,
FlatList,
TouchableOpacity,
} from "react-native";
import { globalStyles } from "../styles/global";
import Card from "../shared/card";
import FlatButton from "../shared/button";
import { TextInput } from "react-native-gesture-handler";
import { AntDesign } from "#expo/vector-icons";
import Weather from "./weather";
export default function Home({ navigation }) {
//add state here
const [reviews, setReviews] = useState([
{ title: "Let's Snowboard", rating: 4, body: "blue", key: 1 },
]);
const [city, setCity] = useState("");
return (
<View style={globalStyles.container}>
<View style={styles.searchBox}>
<TextInput
placeholder="search"
placeholderTextColor="lightcoral"
style={styles.searchText}
onChange={(text) => setCity(text)}
/>
<TouchableOpacity style={styles.buttonTouch} onPress={Weather}>
<AntDesign name="search1" size={28} color="lightcoral" />
</TouchableOpacity>
</View>
<FlatList
data={reviews}
renderItem={({ item }) => (
<TouchableOpacity
onPress={() => navigation.navigate("Weather", item)}
>
<Card>
<Text style={globalStyles.titleText}>{item.title}</Text>
</Card>
</TouchableOpacity>
)}
/>
<FlatButton text="Let's snowboard?" />
</View>
);
}
For my weather screen:
import React, { useState } from "react";
import { StyleSheet, Text, View, Image } from "react-native";
import { globalStyles } from "../styles/global";
const Weather = () => {
const [date, setData] = useState([]);
const [icon, setIcon] = useState("");
const [cityDisplay, setCityDisplay] = useState("");
const [desc, setDesc] = useState("");
const [main, setMain] = useState("");
const [humidity, setHumidity] = useState("");
const [pressure, setPressure] = useState("");
const [visibility, setVisibility] = useState("");
const [temp, setTemp] = useState("");
async function fetchWeather() {
try {
const response = await fetch(
"https://samples.openweathermap.org/data/2.5/weather?q=London,uk&appid=***"
);
const json = await response.json();
setData({ data: json });
setTemp({ temp: (json.main.temp - 273.15).toFixed(2) + " C" });
setCityDisplay({ cityDisplay: json.name });
setIcon({ icon: json.weather[0].icon });
setMain({ main: json.weather[0].main });
setHumidity({ humidity: json.main.humidity + " %" });
setPressure({ pressure: json.main.pressure + " hPa" });
setVisibility({
visibility: (json.visibility / 1000).toFixed(2) + " km",
});
} catch (err) {
console.warn("error");
}
}
return (
<View style={styles.weatherBox}>
<View style={styles.weatherHolder}>
<Image
source={{
uri: "http://openweathermap.org/img/wn/" + setIcon + "#2x.png",
}}
style={styles.weatherImage}
/>
<View>
<Text style={styles.temperature}>{temp}</Text>
<Text>{cityDisplay}</Text>
</View>
</View>
</View>
);
};
Essentially, my goal is to click the card text where it says :let's snowboard. Once clicked, it should redirect me to the weather screen where at the moment, it will show me the current temperature and the name of the city. I am not sure why it's not showing. Im assuming it has something to do with my weather screen.
I had tested out making another simple screen where it would show the values of my current state 'reviews'. I was able to click the card and redirect me to another screen where it shows the rating value and the body.
This is the first time I've dealt with apis. Any guidance would be much appreciated(:

I am fairly certain that you do not actually call the fetchWeather function. In the Weather component you define the function with async function fetchWeather() {...}. However, that is only a function definition. You need to actually call it like this: fetchWeather(); which I think you can do right below the definition like the example below.
async function fetchWeather() {
// code that you want to execute in the function
}
// Actual function call
fetchWeather();
EDIT (concerning state management):
I would definitely recommend reading most of the React Hooks documentation to get a full grasp, but I will still address how you handle state.
At this location in the docs it shows exactly what I believe your issue to be.
Whenever you try to set state you do this: setVariable({ variableName: newValue});, but that is how you are supposed to set state inside of a class. However, fetchWeather() is a function, and functions are supposed to update state like this: setVariable(newValue);

React Native: Passing useState() data to unrelated screens

Explanation: I am creating a fitness app, my fitness app has a component called WorkoutTimer that connects to the workout screen, and that screen is accessed via the HomeScreen. Inside the WorkoutTimer, I have an exerciseCount useState() that counts every time the timer does a complete loop (onto the next exercise). I have a different screen called StatsScreen which is accessed via the HomeScreen tab that I plan to display (and save) the number of exercises completed.
What I've done: I have quite literally spent all day researching around this, but it seems a bit harder with unrelated screens. I saw I might have to use useContext() but it seemed super difficult. I am fairly new to react native so I am trying my best haha! I have attached the code for each screen I think is needed, and attached a screenshot of my homeScreen tab so you can get a feel of how my application works.
WorkoutTimer.js
import React, { useState, useEffect, useRef } from "react";
import {
StyleSheet,
Text,
View,
TouchableOpacity,
Button,
Animated,
Image,
SafeAreaView,
} from "react-native";
import { CountdownCircleTimer } from "react-native-countdown-circle-timer";
import { Colors } from "../colors/Colors";
export default function WorkoutTimer() {
const [count, setCount] = useState(1);
const [exerciseCount, setExerciseCount] = useState(0);
const [workoutCount, setWorkoutCount] = useState(0);
const exercise = new Array(21);
exercise[1] = require("../assets/FR1.png");
exercise[2] = require("../assets/FR2.png");
exercise[3] = require("../assets/FR3.png");
exercise[4] = require("../assets/FR4.png");
exercise[5] = require("../assets/FR5.png");
exercise[6] = require("../assets/FR6.png");
exercise[7] = require("../assets/FR7.png");
exercise[8] = require("../assets/FR8.png");
exercise[9] = require("../assets/S1.png");
exercise[10] = require("../assets/S2.png");
exercise[11] = require("../assets/S3.png");
exercise[12] = require("../assets/S4.png");
exercise[13] = require("../assets/S5.png");
exercise[14] = require("../assets/S6.png");
exercise[15] = require("../assets/S7.png");
exercise[16] = require("../assets/S8.png");
exercise[17] = require("../assets/S9.png");
exercise[18] = require("../assets/S10.png");
exercise[19] = require("../assets/S11.png");
exercise[20] = require("../assets/S12.png");
exercise[21] = require("../assets/S13.png");
return (
<View style={styles.container}>
<View style={styles.timerCont}>
<CountdownCircleTimer
isPlaying
duration={45}
size={240}
colors={"#7B4FFF"}
onComplete={() => {
setCount((prevState) => prevState + 1);
setExerciseCount((prevState) => prevState + 1);
if (count == 21) {
return [false, 0];
}
return [(true, 1000)]; // repeat animation for one second
}}
>
{({ remainingTime, animatedColor }) => (
<View>
<Image
source={exercise[count]}
style={{
width: 150,
height: 150,
}}
/>
<View style={styles.timeOutside}>
<Animated.Text
style={{
color: animatedColor,
fontSize: 18,
position: "absolute",
marginTop: 67,
marginLeft: 35,
}}
>
{remainingTime}
</Animated.Text>
<Text style={styles.value}>seconds</Text>
</View>
</View>
)}
</CountdownCircleTimer>
</View>
</View>
);
}
const styles = StyleSheet.create({})
WorkoutScreen.js
import React, { useState } from "react";
import { StyleSheet, Text, View } from "react-native";
import WorkoutTimer from "../components/WorkoutTimer";
export default function WorkoutScreen() {
return (
<View style={styles.container}>
<WorkoutTimer />
</View>
);
}
const styles = StyleSheet.create({
container: {
flex: 1,
backgroundColor: "#fff",
alignItems: "center",
justifyContent: "center",
},
});
HomeScreen.js
import React from "react";
import { StyleSheet, Text, View, SafeAreaView, Button } from "react-native";
import { TouchableOpacity } from "react-native-gesture-handler";
import { AntDesign } from "#expo/vector-icons";
import { Colors } from "../colors/Colors";
export default function HomeScreen({ navigation }) {
return (
<SafeAreaView style={styles.container}>
<Text style={styles.pageRef}>SUMMARY</Text>
<Text style={styles.heading}>STRETCH & ROLL</Text>
<View style={styles.content}>
<TouchableOpacity
style={styles.timerDefault}
onPress={() => navigation.navigate("WorkoutScreen")}
>
<Button title="START WORKOUT" color={Colors.primary} />
</TouchableOpacity>
<TouchableOpacity
style={styles.statContainer}
onPress={() => navigation.navigate("StatsScreen")}
>
<AntDesign name="barschart" size={18} color={Colors.primary} />
<Text style={{ color: Colors.primary }}>Statistics</Text>
<AntDesign name="book" size={18} color={Colors.primary} />
</TouchableOpacity>
</View>
</SafeAreaView>
);
}
const styles = StyleSheet.create({})
StatsScreen.js
import React from "react";
import { StyleSheet, Text, View } from "react-native";
import { exerciseCount, workoutCount } from "../components/WorkoutTimer";
export default function StatsScreen() {
return (
<View style={styles.container}>
<Text display={exerciseCount} style={styles.exerciseText}>
{exerciseCount}
</Text>
<Text display={workoutCount} style={styles.workoutText}>
{workoutCount}
</Text>
</View>
);
}
const styles = StyleSheet.create({});
Home Screen Image

As far as I can tell, you're almost there! You're trying to get your 2 state
variables from the WorkoutTimer like this:
import { exerciseCount, workoutCount } from "../components/WorkoutTimer";
Unfortunatly this won't work :( . These two variables change throughout your
App's life-time and that kinda makes them "special".
In React, these kinds of variables need to be declared in a parent component
and passed along to all children, which are interested in them.
So in your current Setup you have a parent child relationship like:
HomeScreen -> WorkoutScreen -> WorkoutTimer.
If you move the variables to HomeScreen (HomeScreen.js)
export default function HomeScreen({ navigation }) {
const [exerciseCount, setExerciseCount] = useState(0);
const [workoutCount, setWorkoutCount] = useState(0);
you can then pass them along to WorkoutScreen or StatsScreen with something
like:
navigation.navigate("WorkoutScreen", { exerciseCount })
navigation.navigate("StatsScreen", { exerciseCount })
You'll probably have to read up on react-navigation's documentation for .navigate I'm not sure I remember this correctly.
In order to read the variable you can then:
export default function WorkoutScreen({ navigation }) {
const exerciseCount = navigation.getParam(exerciseCount);
return (
<View style={styles.container}>
<WorkoutTimer exerciseCount={exerciseCount} />
</View>
);
}
and finally show it in the WorkoutTimer:
export default function WorkoutTimer({ exerciseCount }) {
Of course that's just part of the solution, since you'll also have to pass
along a way to update your variables (setExerciseCount and setWorkoutCount).
I encourage you to read through the links I posted and try to get this to work.
After you've accumulated a few of these stateful variables, you might also want to look at Redux, but this is a bit much for now.
Your app looks cool, keep at it!

I ended up solving this problem with useContext if anyone is curious, it was hard to solve initially. But once I got my head around it, it wasn't too difficult to understand.
I created another file called exerciseContext with this code:
import React, { useState, createContext } from "react";
const ExerciseContext = createContext([{}, () => {}]);
const ExerciseProvider = (props) => {
const [state, setState] = useState(0);
//{ exerciseCount: 0, workoutCount: 0 }
return (
<ExerciseContext.Provider value={[state, setState]}>
{props.children}
</ExerciseContext.Provider>
);
};
export { ExerciseContext, ExerciseProvider };
and in App.js I used ExerciseProvider which allowed me to pass the data over the screens.
if (fontsLoaded) {
return (
<ExerciseProvider>
<NavigationContainer>
<MyTabs />
</NavigationContainer>
</ExerciseProvider>
);
} else {
return (
<AppLoading startAsync={getFonts} onFinish={() => setFontsLoaded(true)} />
);
}
}
I could call it with:
import { ExerciseContext } from "../components/ExerciseContext";
and
const [exerciseCount, setExerciseCount] = useContext(ExerciseContext);
This meant I could change the state too! Boom, solved! If anyone needs an explanation, let me know!

I think you have to use Mobx or Redux for state management. That will be more productive for you instead built-in state.

Conditional rendering with React Hooks : loading

I am learning how to use React Hooks and have been stuck for many hours on something that's supposed to be very simple.
I am trying to display a a text if the state variable "loading" is true. If it's false, I want to display something else.
No matter what I try, "loading" is always false or at least, the UI does not appear to reflect its value.
here is the code:
import React, {useState, useEffect} from 'react';
import {View, SafeAreaView, Text} from 'react-native';
const testScreen= (props) => {
const [loading, setLoading ] = useState(true);
useEffect(() => {
setLoading(false);
}, []);
if(loading)
{
return <Text>Hi</Text>;
}
else
{
return<Text.Hey</Text>
}
}
export default testScreen;
Any help will be more than welcome and I am sorry if this is very basic.
UPDATE: Here is the actual code I am working with. SetLoading is supposed to update the state variable to false but never does or at least, the UI des not render.
import React, {useState, useEffect} from 'react';
import {View, SafeAreaView, Text, ActivityIndicator} from 'react-native';
import CategoryTag from '../Components/CategoryTag';
import firestore from '#react-native-firebase/firestore';
const CategoryScreen = (props) => {
const topicCollection = firestore().collection('Topics')
.where("active","==",true);
//hooks for topics
const [topics,setTopics] = useState([]);
const [loading, setLoading ] = useState(true);
//get all active topics
useEffect(() => {
return topicCollection.onSnapshot(querySnapshot => {
const list = [];
querySnapshot.forEach(doc => {
const { active, name } = doc.data();
list.push({
id: doc.id,
active,
name,
});
});
setTopics(list);
setLoading(false);
});
}, []);
const renderTopics = () =>{
return(
topics.map((item) =>{
return(
<CategoryTag key = {item.id}
color={userTopics.includes(item.name) ?"#51c0cc":"#303239"}
name = {item.name}
isSelected = {userTopics.includes(item.name)}
handleClick = {addTopicToUserTopicCollection}
/>
)
})
)
}
if(loading)
{
return (
<SafeAreaView style={{flex:1, backgroundColor:"#455a65"}}>
<View style={{width:200, padding:20, paddingTop:60}}>
<Text style ={{fontSize:25, fontWeight:"bold",
color:"#fff"}}>What are you</Text>
<Text style ={{fontSize:22, color:"#fff"}}>interested in?
</Text>
</View>
<View style={{flex:1, alignItems:"center",
justifyContent:"center", alignSelf:"center"}}>
<ActivityIndicator />
</View>
</SafeAreaView>
)
}
else // this never runs
{
return (
<SafeAreaView style={{flex:1, backgroundColor:"#455a65"}}>
<View>
<View style={{width:200, padding:20, paddingTop:60}}>
<Text style ={{fontSize:25, fontWeight:"bold",
color:"#fff"}}>What are you</Text>
<Text style ={{fontSize:22, color:"#fff"}}>interested in?
</Text>
</View>
<View style ={{flexDirection:"column", paddingTop:20}}>
<View style ={{padding:15, paddingTop:15,
marginBottom:15,
flexWrap:"wrap", flexDirection:"row"}}>
{renderTopics(topics)}
</View>
</View>
</View>
</SafeAreaView>
);
}
}
export default CategoryScreen;

You are immediately setting your setLoading state to false and therefore loading text might be rendering for fraction of second, or not at all, like a glitch. Try setting setLoading with a timeout and then you will see the intended behaviour.
const TestScreen= (props) => {
const [loading, setLoading ] = useState(true);
useEffect(() => {
setTimeout(()=>setLoading(false), 3000);
}, []);
if(loading)
{
return <Text>Hi</Text>;
}
else
{
return<Text>hey</Text>
}
}