I've been following a guide about making use of FlatLists. I have copied code from this GitHub repo: https://github.com/ReactNativeSchool/react-native-flatlist-demo/blob/master/FlatListDemo.js
I'm getting an issue however...
Warning: React.createElement: type is invalid -- expected a string (for built-in components) or a class/function (for composite components) but got: %s.%s%s, undefined, You likely forgot to export your component from the file it's defined in, or you might have mixed up default and named imports.
Here is my code:
import React, { Component } from "react";
import { View, FlatList, ActivityIndicator } from "react-native";
import { List, ListItem, SearchBar } from "react-native-elements";
class SettingsScreen extends Component {
constructor(props) {
super(props);
this.state = {
loading: false,
data: [],
page: 1,
seed: 1,
error: null,
refreshing: false
};
}
componentDidMount() {
this.makeRemoteRequest();
}
makeRemoteRequest = () => {
const { page, seed } = this.state;
const url = `https://randomuser.me/api/?
seed=${seed}&page=${page}&results=20`;
this.setState({ loading: true });
fetch(url)
.then(res => res.json())
.then(res => {
this.setState({
data: page === 1 ? res.results : [...this.state.data, ...res.results],
error: res.error || null,
loading: false,
refreshing: false
});
})
.catch(error => {
this.setState({ error, loading: false });
});
};
handleRefresh = () => {
this.setState(
{
page: 1,
seed: this.state.seed + 1,
refreshing: true
},
() => {
this.makeRemoteRequest();
}
);
};
handleLoadMore = () => {
this.setState(
{
page: this.state.page + 1
},
() => {
this.makeRemoteRequest();
}
);
};
renderSeparator = () => {
return (
<View
style={{
height: 1,
width: "86%",
backgroundColor: "#CED0CE",
marginLeft: "14%"
}}
/>
);
};
renderHeader = () => {
return <SearchBar placeholder="Type Here..." lightTheme round />;
};
renderFooter = () => {
if (!this.state.loading) return null;
return (
<View
style={{
paddingVertical: 20,
borderTopWidth: 1,
borderColor: "#CED0CE"
}}
>
<ActivityIndicator animating size="large" />
</View>
);
};
render() {
return (
<List containerStyle={{ borderTopWidth: 0, borderBottomWidth: 0 }}>
<FlatList
data={this.state.data}
renderItem={({ item }) => (
<ListItem
roundAvatar
title={`${item.name.first} ${item.name.last}`}
subtitle={item.email}
avatar={{ uri: item.picture.thumbnail }}
containerStyle={{ borderBottomWidth: 0 }}
/>
)}
keyExtractor={item => item.email}
ItemSeparatorComponent={this.renderSeparator}
ListHeaderComponent={this.renderHeader}
ListFooterComponent={this.renderFooter}
onRefresh={this.handleRefresh}
refreshing={this.state.refreshing}
onEndReached={this.handleLoadMore}
onEndReachedThreshold={50}
/>
</List>
);
}
}
export default SettingsScreen;
Through looking at sources online I can see it is probably my imports that are breaking the code but I can't see it myself. Any suggestions?
Thanks
Related
I used this tutorial but it didn't work (if you are interested, check out my last post). Any suggestions to make a working search for a flatlist?
I have a list of 100 things and just by inserting the name in a search bar, the flatlist should update with the results.
Try using react-native-searchable-flatlist
import React, { Component } from 'react';
import { View, Text, FlatList, ActivityIndicator } from 'react-native';
import { ListItem, SearchBar } from 'react-native-elements';
class FlatListDemo extends Component {
constructor(props) {
super(props);
this.state = {
loading: false,
data: [],
error: null,
};
this.arrayholder = [];
}
componentDidMount() {
this.makeRemoteRequest();
}
makeRemoteRequest = () => {
const url = `https://randomuser.me/api/?&results=20`;
this.setState({ loading: true });
fetch(url)
.then(res => res.json())
.then(res => {
this.setState({
data: res.results,
error: res.error || null,
loading: false,
});
this.arrayholder = res.results;
})
.catch(error => {
this.setState({ error, loading: false });
});
};
renderSeparator = () => {
return (
<View
style={{
height: 1,
width: '86%',
backgroundColor: '#CED0CE',
marginLeft: '14%',
}}
/>
);
};
searchFilterFunction = text => {
this.setState({
value: text,
});
const newData = this.arrayholder.filter(item => {
const itemData = `${item.name.title.toUpperCase()} ${item.name.first.toUpperCase()} ${item.name.last.toUpperCase()}`;
const textData = text.toUpperCase();
return itemData.indexOf(textData) > -1;
});
this.setState({
data: newData,
});
};
renderHeader = () => {
return (
<SearchBar
placeholder="Type Here..."
lightTheme
round
onChangeText={text => this.searchFilterFunction(text)}
autoCorrect={false}
value={this.state.value}
/>
);
};
render() {
if (this.state.loading) {
return (
<View style={{ flex: 1, alignItems: 'center', justifyContent: 'center' }}>
<ActivityIndicator />
</View>
);
}
return (
<View style={{ flex: 1 }}>
<FlatList
data={this.state.data}
renderItem={({ item }) => (
<ListItem
leftAvatar={{ source: { uri: item.picture.thumbnail } }}
title={`${item.name.first} ${item.name.last}`}
subtitle={item.email}
/>
)}
keyExtractor={item => item.email}
ItemSeparatorComponent={this.renderSeparator}
ListHeaderComponent={this.renderHeader}
/>
</View>
);
}
}
export default FlatListDemo;
I am totally new in React Native, I am having problem rendering data from API call. When I do it inside function it is working for me when I am using useEffect... but in the Class I cannot use that.
Here is example of my code...
export default class Categories extends React.Component {
constructor(props) {
super(props);
this.state = {
loading: false,
data: [],
error: null,
};
}
componentDidMount() {
this.regionsGetRequest();
}
regionsGetRequest = () => {
this.setState({ loading: true });
const fetchData = async () => {
const result = await axios(
'https://...........json'
);
this.setState({
data: result.data,
error: result.error || null,
loading: false,
});
};
fetchData();
};
renderCategories = () => {
const categoryLive = this.state.data;
console.log(JSON.stringify(categoryLive));
I am getting in console: undefined, undefined... and then results as they should... like it is running 3 times for some reason... if I try to put above renderCategories:
componentDidMount() {
renderCategories();
}
I am getting just one undefined... when I connect variable categoryLive nothing is loading.
Sorry I have been strugling with this one... any help is really appreciated!!
No matter what I do, I am always getting 3 calls... first two empty object [], and third I get real results dumped in console. So my categories are not rendering.. they are empty.
Here is updated code, and I am posting whole file, it might ring some bells.
export default class Categories extends React.Component {
state = {
myData: [],
};
componentDidMount() {
axios
.get('https://..............json')
.then((res) => {
const myData = res.data;
this.setState({ myData });
});
}
renderCategories = () => {
const categoryLive = this.state.myData;
console.log(JSON.stringify(categoryLive));
const { navigation, route } = this.props;
const tabId = route.params?.tabId;
const categories = tabId
? categoryLive[tabId]
: categoryLive.victoria_bc;
//console.log(route.params?.tabId);
return (
<ScrollView
showsVerticalScrollIndicator={false}
contentContainerStyle={styles.categoryList}
>
<Block flex>
{categories.map((category) => (
<TouchableWithoutFeedback
key={`category-${category.id}`}
onPress={() => navigation.navigate('Category', { ...category })}
>
<Block flex card style={[styles.category, styles.shadow]}>
<ImageBackground
source={{ uri: category.image }}
style={[
styles.imageBlock,
{ width: width - theme.SIZES.BASE * 2, height: 252 },
]}
imageStyle={{
width: width - theme.SIZES.BASE * 2,
height: 252,
}}
>
<Block style={styles.categoryTitle}>
<Text size={18} bold color={theme.COLORS.WHITE}>
{category.title}
</Text>
</Block>
</ImageBackground>
</Block>
</TouchableWithoutFeedback>
))}
</Block>
</ScrollView>
);
};
render() {
return (
<Block flex center style={styles.categories}>
{this.renderCategories()}
</Block>
);
}
}
When I put it like this: I am getting default category ( and all data just fine... ) but my navigation is not working any more... (route.params?.tabId is not updating)
axios
.get('https://.............json')
.then((res) => {
this.setState({
myData: res.data,
error: res.error || null,
loading: false,
});
console.log('inside .then----' + JSON.stringify(this.state.myData));
const { navigation, route } = this.props;
const tabId = route.params?.tabId;
const tmpCategories = tabId
? this.state.myData[tabId]
: this.state.myData.victoria_bc;
this.setState({ categories: tmpCategories });
//console.log(route.params?.tabId);
});
If I put it like this as below... category is empty for me:
axios
.get('https://.............json')
.then((res) => {
this.setState({
myData: res.data,
error: res.error || null,
loading: false,
});
console.log('inside .then----' + JSON.stringify(this.state.myData));
});
const { navigation, route } = this.props;
const tabId = route.params?.tabId;
const tmpCategories = tabId
? this.state.myData[tabId]
: this.state.myData.victoria_bc;
this.setState({ categories: tmpCategories });
//console.log(route.params?.tabId);
Final code that is working for me..
export default class Categories extends React.Component {
constructor(props) {
super(props);
this.state = {
loading: true,
myData: [],
error: null,
};
}
componentDidMount() {
this.renderCategories();
}
renderCategories = () => {
axios
.get('https://.............json')
.then((res) => {
this.setState({
myData: res.data,
error: res.error || null,
loading: false,
});
//console.log('inside .then----' + JSON.stringify(this.state.myData));
});
};
render() {
if (this.state.loading) {
return (
<View
style={{ flex: 1, alignItems: 'center', justifyContent: 'center' }}
>
<ActivityIndicator />
</View>
);
} else {
const { navigation, route } = this.props;
const tabId = route.params?.tabId;
const categories = tabId
? this.state.myData[tabId]
: this.state.myData.victoria_bc;
//console.log(route.params?.tabId);
return (
<Block flex center style={styles.categories}>
<ScrollView
showsVerticalScrollIndicator={false}
contentContainerStyle={styles.categoryList}
>
<Block flex>
{categories.map((category) => (
<TouchableWithoutFeedback
key={`category-${category.id}`}
onPress={() =>
navigation.navigate('Category', { ...category })
}
>
<Block flex card style={[styles.category, styles.shadow]}>
<ImageBackground
source={{ uri: category.image }}
style={[
styles.imageBlock,
{ width: width - theme.SIZES.BASE * 2, height: 252 },
]}
imageStyle={{
width: width - theme.SIZES.BASE * 2,
height: 252,
}}
>
<Block style={styles.categoryTitle}>
<Text size={18} bold color={theme.COLORS.WHITE}>
{category.title}
</Text>
</Block>
</ImageBackground>
</Block>
</TouchableWithoutFeedback>
))}
</Block>
</ScrollView>
</Block>
);
}
}
}
export default class Categories extends React.Component {
constructor(props) {
super(props);
this.state = {
loading: false,
myData: [],
error: null,
categories: []
};
}
componentDidMount() {
renderCategories();
}
renderCategories = () => {
this.setState({ loading: true });
axios
.get('https://..............json')
.then((res) => {
this.setState({ myData: res.data,
error: res.error || null,
loading: false
});
const categoryLive = this.state.myData;
console.log(JSON.stringify(categoryLive));
});
};
render() {
// Set params in your render method :
const { navigation, route } = this.props;
const tabId = route.params?.tabId;
if (this.state.loading){
return (
<View style={{ flex : 1, alignItems: 'center', justifyContent: 'center' }}>
<ActivityIndicator/>
</View>
);
}
return (
// assign in your return statement
this.setState({ categories: tabId
? categoryLive[tabId]
: categoryLive.victoria_bc;})
//console.log(route.params?.tabId);
const { categories } = this.state.categories;
<Block flex center style={styles.categories}>
<ScrollView
showsVerticalScrollIndicator={false}
contentContainerStyle={styles.categoryList}
>
<Block flex>
{categories.map((category) => (
<TouchableWithoutFeedback
key={`category-${category.id}`}
onPress={() => navigation.navigate('Category', { ...category })}
>
<Block flex card style={[styles.category, styles.shadow]}>
<ImageBackground
source={{ uri: category.image }}
style={[
styles.imageBlock,
{ width: width - theme.SIZES.BASE * 2, height: 252 },
]}
imageStyle={{
width: width - theme.SIZES.BASE * 2,
height: 252,
}}
>
<Block style={styles.categoryTitle}>
<Text size={18} bold color={theme.COLORS.WHITE}>
{category.title}
</Text>
</Block>
</ImageBackground>
</Block>
</TouchableWithoutFeedback>
))}
</Block>
</ScrollView>
</Block>
);
}
}
I am trying to create a searchable flatlist on this new app I was working on over quarantine. I followed an article on the internet on how to create it and my code so far looks like this:
import React, { Component } from 'react';
import { View, Text, FlatList, ActivityIndicator } from 'react-native';
import { ListItem, SearchBar } from 'react-native-elements';
class FlatListDemo extends Component {
constructor(props) {
super(props);
this.state = {
loading: false,
data: [],
error: null,
};
this.arrayholder = [];
}
componentDidMount() {
this.makeRemoteRequest();
}
makeRemoteRequest = () => {
const url = `https://randomuser.me/api/?&results=20`;
this.setState({ loading: true });
fetch(url)
.then(res => res.json())
.then(res => {
this.setState({
data: res.results,
error: res.error || null,
loading: false,
});
this.arrayholder = res.results;
})
.catch(error => {
this.setState({ error, loading: false });
});
};
renderSeparator = () => {
return (
<View
style={{
height: 1,
width: '86%',
backgroundColor: '#CED0CE',
marginLeft: '14%',
}}
/>
);
};
searchFilterFunction = text => {
this.setState({
value: text,
});
const newData = this.arrayholder.filter(item => {
const itemData = `${item.name.title.toUpperCase()} ${item.name.first.toUpperCase()} ${item.name.last.toUpperCase()}`;
const textData = text.toUpperCase();
return itemData.indexOf(textData) > -1;
});
this.setState({
data: newData,
});
};
renderHeader = () => {
return (
<SearchBar
placeholder="Type Here..."
lightTheme
round
onChangeText={text => this.searchFilterFunction(text)}
autoCorrect={false}
value={this.state.value}
/>
);
};
render() {
if (this.state.loading) {
return (
<View style={{ flex: 1, alignItems: 'center', justifyContent: 'center' }}>
<ActivityIndicator />
</View>
);
}
return (
<View style={{ flex: 1 }}>
<FlatList
data={this.state.data}
renderItem={({ item }) => (
<ListItem
leftAvatar={{ source: { uri: item.picture.thumbnail } }}
title={`${item.name.first} ${item.name.last}`}
subtitle={item.email}
/>
)}
keyExtractor={item => item.email}
ItemSeparatorComponent={this.renderSeparator}
ListHeaderComponent={this.renderHeader}
/>
</View>
);
}
}
export default FlatListDemo;
This works and all, but how could I alter the makeRemoteRequest function so that I got data from a local json file instead of a url? For example:
makeRemoteRequest = () => {
const url = `../data/userData.json`;
this.setState({ loading: true });
fetch(url)
.then(res => res.json())
.then(res => {
this.setState({
data: res.results,
error: res.error || null,
loading: false,
});
this.arrayholder = res.results;
})
.catch(error => {
this.setState({ error, loading: false });
});
};
I tried this with no success as none of the json data rendered and appeared in the flatlist
The Fetch API is a promise-based JavaScript API for making asynchronous HTTP requests in the browser similar to XMLHttpRequest. If you want to load data from a local JSON file.
First import that file
import Data from '../data/userData.json'
Then assign imported value to your state inside your makeRemoteRequest function
makeRemoteRequest = () => {
this.setState({
data: Data,
});
}
Hope this helps you. Feel free for doubts.
am using react native API to display data in to FlatList and unfortunately getting below error:
Error : Element type is invalid: expected a string.
So far I have done as below:
import React, { Component } from "react";
import { View, Text, FlatList,List } from "react-native";
// import {Row} from './Row';
export default class FlatListDemo extends Component {
constructor(props) {
super(props);
this.state = {
loading: false,
data: [],
page: 1,
seed: 1,
error: null,
refreshing: false,
};
}
componentDidMount() {
this.makeRemoteRequest();
}
makeRemoteRequest = () => {
const { page, seed } = this.state;
const url = `https://randomuser.me/api/?seed=${seed}&page=${page}&results=20`;
this.setState({ loading: true });
fetch(url)
.then(res => res.json())
.then(res => {
this.setState({
data: page === 1 ? res.results : [...this.state.data, ...res.results],
error: res.error || null,
loading: false,
refreshing: false
});
})
.catch(error => {
this.setState({ error, loading: false });
});
};
render() {
return (
<View style={{ flex: 1, alignItems: "center", justifyContent: "center" }}>
<List>
<FlatList
data={this.state.data}
renderItem={({ item }) => (
<ListItem
roundAvatar
title={`${item.name.first} ${item.name.last}`}
subtitle={item.email}
avatar={{ uri: item.picture.thumbnail }}
/>
)}
keyExtractor={item => item.email}
/>
</List>
</View>
);
}
}
So, I have tried resolving from last two hours but stacked there. What might be the issue?
Remove List Component from Your Code and Try.
I'm trying to make an auto-refreshing flatlist every time the user types something, like Instagram’s search does.
The compiler keeps complaining about a missing variable called search.
import React, { Component } from "react";
import { View, Text, FlatList, ActivityIndicator } from "react-native";
import { List, ListItem, SearchBar } from "react-native-elements";
export default class Home extends Component {
constructor(props) {
super(props);
this.state = {
loading: false,
data: [],
page: 1,
error: null,
search: '',
};
}
componentDidMount() {
this.makeRemoteRequest();
}
makeRemoteRequest = () => {
const { page, search } = this.state;
const url = `https://pacific-basin-57759.herokuapp.com/api/account/users?page=${page}&search=${search}`;
this.setState({ loading: true });
fetch(url)
.then(res => res.json())
.then(res => {
this.setState({
data: page === 1 ? res.results : [...this.state.data, ...res.results],
error: res.error || null,
loading: false,
search: this.state.search
})
})
.catch(error => {
this.setState({ error, loading: false });
});
};
handleLoadMore = () => {
this.setState(
{
page: this.state.page + 1
},
() => {
this.makeRemoteRequest();
}
);
};
handleSearch = () => {
this.setState(
{
search: this.state.search
},
() => {
this.makeRemoteRequest();
}
);
}
renderSeparator = () => {
return (
<View
style={{
height: 1,
width: "86%",
backgroundColor: "#CED0CE",
marginLeft: "14%"
}}
/>
);
};
renderHeader = () => {
return <SearchBar placeholder="Type Here..." lightTheme round onChangeText={(text) => this.setState({search:text})} />;
};
renderFooter = () => {
if (!this.state.loading) return null;
return (
<View
style={{
paddingVertical: 20,
borderTopWidth: 1,
borderColor: "#CED0CE"
}}
>
<ActivityIndicator animating size="large" />
</View>
);
};
render() {
return (
<List containerStyle={{ borderTopWidth: 0, borderBottomWidth: 0 }}>
<FlatList
data={this.state.data}
renderItem={({ item }) => (
<ListItem
//roundAvatar
title={`${item.first_name} ${item.last_name}`}
subtitle={item.username}
//avatar={{ uri: item.picture.thumbnail }}
containerStyle={{ borderBottomWidth: 0 }}
/>
)}
keyExtractor={item => item.id}
ItemSeparatorComponent={this.renderSeparator}
ListHeaderComponent={this.renderHeader}
ListFooterComponent={this.renderFooter}
onEndReached={this.handleLoadMore}
onEndReachedThreshold={0.5}
/>
</List>
);
}
}`
I've looked at the Fetch API documentation at MDN and it doesn't really give any useful info (it's all over the place).