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} ${item.name.last}`}
subtitle={item.email}
avatar={{ uri: item.picture.thumbnail }}
/>
)}
keyExtractor={item => item.email}
/>
</List>
</View>
);
}
}
So, I have tried resolving from last two hours but stacked there. What might be the issue?
Remove List Component from Your Code and Try.
Related
I used this tutorial but it didn't work (if you are interested, check out my last post). Any suggestions to make a working search for a flatlist?
I have a list of 100 things and just by inserting the name in a search bar, the flatlist should update with the results.
Try using react-native-searchable-flatlist
import React, { Component } from 'react';
import { View, Text, FlatList, ActivityIndicator } from 'react-native';
import { ListItem, SearchBar } from 'react-native-elements';
class FlatListDemo extends Component {
constructor(props) {
super(props);
this.state = {
loading: false,
data: [],
error: null,
};
this.arrayholder = [];
}
componentDidMount() {
this.makeRemoteRequest();
}
makeRemoteRequest = () => {
const url = `https://randomuser.me/api/?&results=20`;
this.setState({ loading: true });
fetch(url)
.then(res => res.json())
.then(res => {
this.setState({
data: res.results,
error: res.error || null,
loading: false,
});
this.arrayholder = res.results;
})
.catch(error => {
this.setState({ error, loading: false });
});
};
renderSeparator = () => {
return (
<View
style={{
height: 1,
width: '86%',
backgroundColor: '#CED0CE',
marginLeft: '14%',
}}
/>
);
};
searchFilterFunction = text => {
this.setState({
value: text,
});
const newData = this.arrayholder.filter(item => {
const itemData = `${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} ${item.name.last}`}
subtitle={item.email}
/>
)}
keyExtractor={item => item.email}
ItemSeparatorComponent={this.renderSeparator}
ListHeaderComponent={this.renderHeader}
/>
</View>
);
}
}
export default FlatListDemo;
I am trying to create a searchable flatlist on this new app I was working on over quarantine. I followed an article on the internet on how to create it and my code so far looks like this:
import React, { Component } from 'react';
import { View, Text, FlatList, ActivityIndicator } from 'react-native';
import { ListItem, SearchBar } from 'react-native-elements';
class FlatListDemo extends Component {
constructor(props) {
super(props);
this.state = {
loading: false,
data: [],
error: null,
};
this.arrayholder = [];
}
componentDidMount() {
this.makeRemoteRequest();
}
makeRemoteRequest = () => {
const url = `https://randomuser.me/api/?&results=20`;
this.setState({ loading: true });
fetch(url)
.then(res => res.json())
.then(res => {
this.setState({
data: res.results,
error: res.error || null,
loading: false,
});
this.arrayholder = res.results;
})
.catch(error => {
this.setState({ error, loading: false });
});
};
renderSeparator = () => {
return (
<View
style={{
height: 1,
width: '86%',
backgroundColor: '#CED0CE',
marginLeft: '14%',
}}
/>
);
};
searchFilterFunction = text => {
this.setState({
value: text,
});
const newData = this.arrayholder.filter(item => {
const itemData = `${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.
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} ${item.name.last}`}
subtitle={item.email}
avatar={{ uri: item.picture.thumbnail }}
containerStyle={{ borderBottomWidth: 0 }}
/>
)}
keyExtractor={item => item.email}
ItemSeparatorComponent={this.renderSeparator}
ListHeaderComponent={this.renderHeader}
ListFooterComponent={this.renderFooter}
onRefresh={this.handleRefresh}
refreshing={this.state.refreshing}
onEndReached={this.handleLoadMore}
onEndReachedThreshold={50}
/>
</List>
);
}
}
export default SettingsScreen;
Through looking at sources online I can see it is probably my imports that are breaking the code but I can't see it myself. Any suggestions?
Thanks
This is the tutorial's link(https://medium.com/react-native-development/how-to-use-the-flatlist-component-react-native-basics-92c482816fe6) from where I'm learning react-native.
Everything is working fine except the view is not scrolling
import React, { Component } from 'react';
import { FlatList, Text, View } from 'react-native';
import { List, ListItem } from "react-native-elements";
type Props = {}
export default class FlatListDemo extends Component<Props> {
constructor(props) {
super(props);
this.state = {
loading: false,
data: [],
page: 1,
seed: 1,
error: null,
refreshing: false,
};
}
componentDidMount() {
this.makeRemoteRequest();
}
makeRemoteRequest = () => {
const { page, seed } = this.state;
const url = `https://randomuser.me/api/?seed=${seed}&page=${page}&results=20`;
this.setState({
loading: true
});
fetch(url)
.then(res => res.json())
.then(res => {
this.setState({
data: page === 1 ? res.results : [...this.state.data, ...res.results],
error: res.error || null,
loading: false,
refreshing: false
})
})
.catch(error =>
this.setState({
error,
loading: false
})
)
};
renderSeparator = () => {
return (
<View
style={{
height: 1,
width: "86%",
backgroundColor: "#CED0CE",
marginLeft: "14%"
}}
>
</View>
)
};
render() {
return (
<FlatList
data={this.state.data}
renderItem={({ item }) => (
<ListItem
roundAvatar
title={`${item.name.first} ${item.name.last}`}
subtitle={item.email}
avatar={{ uri: item.picture.thumbnail }}
containerStyle={{ borderBottomWidth: 0 }}
/>
)}
ItemSeparatorComponent={this.renderSeparator}
onEndReachedThreshold={50}
/> )
}}
Is it compulsory to use ScrollView to make able to scroll react-native view or we can do it
using any CSS or something else
When I tried to run this code in this given link: https://snack.expo.io/rkOsCaiD7 to find for a solution what I found was scroll view was working fine with the above code. Just try to reload and run it in react native by which I feel it might resolve your issue.
I'm trying to make an auto-refreshing flatlist every time the user types something, like Instagram’s search does.
The compiler keeps complaining about a missing variable called search.
import React, { Component } from "react";
import { View, Text, FlatList, ActivityIndicator } from "react-native";
import { List, ListItem, SearchBar } from "react-native-elements";
export default class Home extends Component {
constructor(props) {
super(props);
this.state = {
loading: false,
data: [],
page: 1,
error: null,
search: '',
};
}
componentDidMount() {
this.makeRemoteRequest();
}
makeRemoteRequest = () => {
const { page, search } = this.state;
const url = `https://pacific-basin-57759.herokuapp.com/api/account/users?page=${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).