I am trying to achieve pagination for infinite scrolling in react native. When loading, I want to render the loading spinner at the bottom of the Flat list component. (Note: I'm using Expo for this app)
const renderFooter = () => {
if (!category.loading) return null;
return (
<View style={spinnerStyles.container}>
<ActivityIndicator animating size="large" color="#0000ff" />
</View>
);
};
return (
<View style={styles.container}>
<FlatList
columnWrapperStyle={{ justifyContent: "space-between" }}
numColumns={2}
data={category.data}
renderItem={categoryItem}
keyExtractor={(item) => item._id + item.sub_category}
onEndReachedThreshold={0}
listFooterComponent={renderFooter}
onEndReached={() => loadMore()}
/>
</View>
);
The loading spinner not correctly working with the flat list footer.
Has anyone run into this issue before, or does anyone have a solution?
Sorry, it's my simple syntax error. It's actually ListFooterComponent not listFooterComponent. Now it's working fine, Thank you.
Instead of calling the refrence, call the function. It should look something like this.
ListFooterComponent={renderFooter()}
I'm working on a react-native app and I have to put a list of object in a Scrollview, so I use the FlatList component to do it. This is the piece of code that generates the error:
<ScrollView contentContainerStyle={style}>
Other components
<FlatList
style={style}
data={data}
scrollEnabled={false}
keyExtractor={(item, index) => index.toString()}
renderItem={({ item, index}) => (somethings)}
/>
Other components
</ScrollView>
The complete error is: VirtualizedLists should never be nested inside plain ScrollViews with the same orientation because it can break windowing and other functionality - use another VirtualizedList-backed container instead.
Avoid using FlatList with the same orientation. Instead, restructure your code like this --
<ScrollView contentContainerStyle={style}>
Other components
{
data.map((item)=> <Somthing item={item}/>)
}
Other components
</ScrollView>
Flatlist has its own ScrollView you can scroll through the list using that so there is no need to put a flatlist into a ScrollView that is why its giving a warning, the both scrollview will clash and one of them (mostly the parent one) works.
The error is self explanatory and it should be in a developers best interest to avoid these kind of things even when it's just a false alarm.
Your particular situation could use the following solution:
<FlatList
data={data}
keyExtractor={(item, index) => `key-${index}`}
ListHeaderComponent={() => (
<SomeComponents>
...Some components those need to be on top of the list
</SomeComponents>
)}
ListFooterComponent={() => (
<SomeComponents>
...Some components those need to be below the list
</SomeComponents>
)}
renderItem={({ item, index}) => (somethings)}
/>
Another note, if you need more complex list that needs header and footer for the list itself, you can try SectionList.
Your component FlatList and ScrollView have the same orientation(vertical), so you need put your component inside a ScrollView with horizontal orientation like this:
<View>
<ScrollView nestedScrollEnabled={true} style={{ width: "100%" }} >
<View>
<ScrollView horizontal={true} style={{ width: "100%" }}>
<FlatList />
</ScrollView>
</View>
</ScrollView>
</View>
Solution 1: Use FlatList props ListHeaderComponent and create all of your page top section in that. Something like this:
This will not show any warning or error.
Solution 2:
Because only parent view will scroll (ScrollView) and not the child FlatList, so to get rid of the warning you can pass a prop scrollEnabled={false} to the FlatList.
If it doesn't go then import LogBox from react-native and write this in your component
useEffect(() => {
LogBox.ignoreLogs(["VirtualizedLists should never be nested"])
}, [])
hopefully, the warning will be removed.
Anyone want to solve this issue can use a custom VirtualizedScrollView like this:
import React from 'react';
import { FlatList } from 'react-native';
const VirtualizedScrollView = props => {
return (
<FlatList
{...props}
data={[]}
keyExtractor={(e, i) => 'dom' + i.toString()}
ListEmptyComponent={null}
renderItem={null}
ListHeaderComponent={() => (
<>{props.children}</>
)}
/>
);
};
export default VirtualizedScrollView;
Then if you use FlatList inside VirtualizedScrollView, it won't get the warning/error.
<VirtualizedScrollView>
<FlatList
/*--- your props ---*/
/>
</VirtualizedScrollView>
There is a npm package where I get this code, you can also use this package
Solution:
I have also encountered same problem with FlatList. Then the package below solved my problem.
'react-native-virtualized-view'
import { ScrollView } from 'react-native-virtualized-view'
if ScrollView is Vertical change Flatlist Horizontal
<ScrollView >
<FlatList
horizontal
data={lenders}
keyExtractor={(_, index) => index}
renderItem={(item) => {
return <Text>item</Text>
}}
/>
You can solve the 2 vertical ones(I'm assuming their side by side, separated with a segemented control?) by using the same flat list and switching out the data when it's switched. If they're just two vertical flat list's one after another use the SectionList.
For the horizontal one you can try putting the Horizontal FlatList in the ListHeaderComponent of the vertical FlatList and see what happens. It can be janky if you use a vertical FlatList in a vertical scroll view but maybe with two different axis it might be ok. The other option is two only show a few items in the horizontal scrollview and have a "Show More".
The last option is too re design/rethink the page so it's not doing so much. On mobile less is more and developers/designers like to get in the mindset of porting desktop thinking onto mobile. Might be worth a shot.
I used the SectionList approach to solve this & wanted to post a code example because I found the Section data required by React Native to be clear but also quite prescriptive.
renderList = ({empty, posts}: {empty: boolean, posts: Array<Object>}) => (
<SectionList
sections={[
{type: 'MAP', data: [{}]}, // Static sections.
{type: 'PROFILE', data: [{}]},
{type: 'POSTS', data: posts} // Dynamic section data replaces the FlatList.
]}
keyExtractor={(item, index) => index}
renderItem={({item, section}) => {
switch (section.type) {
// Different components for each section type.
case 'MAP':
return <MapView />;
case 'PROFILE':
return <Profile />;
case 'POSTS':
return <Post item={item} />;
default:
return null;
}
}}
ItemSeparatorComponent={() => <Separator />}
ListFooterComponent={() => <>{empty && <EmptyList />}</>}
/>
);
What's nice is that the content feels logically quite separate, so you can add sections easily or have different dynamic data sources.
(If you're building a form & want better keyboard handling, you could also try a KeyboardAwareSectionList from react-native-keyboard-aware-scroll-view.)
Flatlist has an integrated scrollview itself, so you can resolve this error by removing ScrollView Component, And let just the Fatlist component
Error ? you are trying to render a FlatList component inside a scrollview component, this is what is throwing the warning.
solution Render the components using Flatlist's ListHeaderComponent={} prop, i.e in your flatlist add the prop as follows
const FlatList_Header = () => {
return (
<View style={{
height: 45,
width: "100%",
backgroundColor: "#00B8D4",
justifyContent: 'center',
alignItems: 'center'
}}
>
<Text style={{ fontSize: 24, color: 'white' }}> Sample FlatList Header </Text>
</View>
);
}
<FlatList
data={BirdsName}
renderItem={({ item }) => <ItemRender name={item.name} />}
keyExtractor={item => item.id}
ItemSeparatorComponent={ItemDivider}
**ListHeaderComponent={FlatList_Header}**
ListHeaderComponentStyle={{ borderBottomColor: 'red', borderBottomWidth: 2 }}
/>
Note the use of the ListHeaderComponent in the code above, that should supress the warning.
Use flatList like this ListHeaderComponent and ListFooterComponent:
<FlatList ListHeaderComponent={
<ScrollView
style={styles.yourstyle}
showsVerticalScrollIndicator={false}
>
<View style={styles.yourstyle}>
</View>
</ScrollView>
}
data={this.state.images}
renderItem={({ item, index }) => {
return (
<View
style={styles.yourstyle}
>
<Image
source={{
uri: item,
}}
style={styles.yourstyle}
resizeMode={"contain"}
/>
<Text
numberOfLines={2}
ellipsizeMode="tail"
style={styles.yourstyle}
>
{item.name}
</Text>
</View>
);
}}
keyExtractor={({ name }, index) => index.toString()}
ListFooterComponent={
<View style={styles.yourstyle}></View>
}
/>
In my case it was happening due to nesting of ScrollView.
Try replacing some of the ScrollView from children components with React.Fragment.
The solution is very simple, please do not put the Flatlist component in the ScrollView.
They both have the same functionality but Flatlist has advantages and is more stable to use.
im using react native to create an app for a legal document. i need the document to be scrollable. i rendered it using VirtualizedList.
thing is when i try to use scrollToIndex(index: 'something') performance is too slow.
my list contains about 4000 rendered items (each being about a paragraph long).
is there any way to make this run smoother?
export default function App() {
const scroller = useRef();
return (
<SafeAreaView>
<View style={styles.upperContainer}>
<CustomButton
onPress={() => {
scroller.current.scrollToIndex({ index: 1547 });
}}
/>
</View>
<View style={styles.flatContainer}>
<VirtualizedList
ref={scroller}
data={data}
renderItem={({ item }) => (
<CustomText data={item.content} type={item.type} />
)}
getItem={(data, index) => data[index]}
getItemCount={(data) => data.length}
keyExtractor={(item) => item.number.toString()}
initialNumToRender={4000}
onScrollToIndexFailed={() => {
alert('error');
}}
/>
</View>
</SafeAreaView>
);
}
This question is similar to these ones and maybe you can reference some of the answers and see what works for your case. Basically, you need a pure component to make this work.
Link - Flatlist performance slow
Link - VirtualizedList: You have a large list that is slow to update
I you put an Algolia connected component in a header of a FlatList it's as if it enters an infinite loop of queries. The connectInfiniteHits runs constantly.
This is really annoying if you like to put some simple filters in the headers of a list of hits.
My setup is like this:
I have a FlatList that is wrapped by the connectInfiniteHits HOC.
The ListHeaderComponent contains a component this is wrapped by the connectRefinementList HOC. The same problem occurs with a connectSearchBox HOC.
Has anyone seen this and found a solution?
I manage to make it work with those lines:
const RefinementList = connectRefinementList(({ items, refine }) => (
<View>
{items.map(item => (
<TouchableOpacity key={item.label} onPress={() => refine(item.value)}>
<Text style={{ fontWeight: item.isRefined ? '600' : 'normal' }}>
{item.label}
</Text>
</TouchableOpacity>
))}
</View>
));
const InfiniteHits = connectInfiniteHits(({ hits, hasMore, refine }) => (
<FlatList
data={hits}
keyExtractor={item => item.objectID}
onEndReached={() => hasMore && refine()}
ListHeaderComponent={<RefinementList attribute="brand" />}
renderItem={({ item }) => (
<View>
<Text>{JSON.stringify(item).slice(0, 100)}</Text>
</View>
)}
/>
));
Note that I'm not using the function version which indeed breaks.
I have a datasource with more than 800 entries which I'm using FlatList to render it.
Each renderItem receives a function to navigate to another screen on item press.
The problem is that the transition between screens is extremely slow.
I noticed that even with scrolling working fast, renderItem is still being called for all 800 entries in DOM. When all items are finally rendered, then the navigation works fine.
I've tried using initialNumToRender, getItemLayout and waitForInteraction props, as well tried to change my renderItem component (now is a stateless component) to a pure component. Nothing seems to work so far.
Any suggestion will be appreciated.
Here's some code if may help:
<FlatList
data={this.state.listDataSource}
renderItem={({ item, index }) => this.renderListItem(item, index)}
keyExtractor={this._keyExtractor}
style={{
flex: 1,
marginHorizontal: 30,
borderTopWidth: 1,
borderColor: '#919191',
}}/>
renderListItem(item, index) {
return <ListItem dotFunc={() => this.onListItemPress(index)} item={item} />;
}
onListItemPress(index) {
Actions.itemDetail({
index
});
}
// ListItem.js correctly exported
const ListItem = ({ dotFunc, item }) => (
<TouchableOpacity onPress={() => Actions.contactDetail({rowID})}>
<Text>{Item}</Text>
</TouchableOpacity>
}
Thanks