React-Native another VirtualizedList-backed container

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After upgrading to react-native 0.61 i get a lot of warnings like that:

VirtualizedLists should never be nested inside plain ScrollViews with the same orientation - use another VirtualizedList-backed container instead.

What is the other VirtualizedList-backed container that i should use, and why is it now advised not to use like that?

25 Answers

If someone's still looking for a suggestion to the problem that @Ponleu and @David Schilling have described here (regarding content that goes above the FlatList), then this is the approach I took:

<SafeAreaView style={{flex: 1}}>
    <FlatList
      data={data}
      ListHeaderComponent={ContentThatGoesAboveTheFlatList}
      ListFooterComponent={ContentThatGoesBelowTheFlatList} />
</SafeAreaView>

You can read more about this here: https://facebook.github.io/react-native/docs/flatlist#listheadercomponent

Hopefully it helps someone. :)

Just in case this helps someone, this is how I fixed the error in my case.

I had a FlatList nested inside a ScrollView:

render() {
    return (
        <ScrollView>
            <Text>{'My Title'}</Text>
            <FlatList
                data={this.state.myData}
                renderItem={({ item }) => {
                    return <p>{item.name}</p>;
                }}
            />
            {this.state.loading && <Text>{'Loading...'}</Text>}
        </ScrollView>
    );
}

and I got rid of the ScrollView by using the FlatList to render everything I needed, which got rid of the warning:

render() {
    const getHeader = () => {
        return <Text>{'My Title'}</Text>;
    };

    const getFooter = () => {
        if (this.state.loading) {
            return null;
        }
        return <Text>{'Loading...'}</Text>;
    };

    return (
        <FlatList
            data={this.state.myData}
            renderItem={({ item }) => {
                return <p>{item.name}</p>;
            }}
            ListHeaderComponent={getHeader}
            ListFooterComponent={getFooter}
        />
    );
}

The best way is to disable that warning because sometimes Flatlist need to be in ScrollView.

UPDATE RN V0.63 ABOVE

YellowBox is now changed and replace with LogBox

FUNCTIONAL

import React, { useEffect } from 'react';
import { LogBox } from 'react-native';

useEffect(() => {
    LogBox.ignoreLogs(['VirtualizedLists should never be nested']);
}, [])

CLASS BASED

import React from 'react';
import { LogBox } from 'react-native';

componentDidMount() {
    LogBox.ignoreLogs(['VirtualizedLists should never be nested']);
}

UPDATE RN V0.63 BELOW

FUNCTIONAL

import React, { useEffect } from 'react';
import { YellowBox } from 'react-native';

useEffect(() => {
    YellowBox.ignoreWarnings(['VirtualizedLists should never be nested']);
}, [])

CLASS BASED

import React from 'react';
import { YellowBox } from 'react-native';

componentDidMount() {
    YellowBox.ignoreWarnings(['VirtualizedLists should never be nested']);
}

Data

// dummy data array
const data = [
    {id: 1, name: 'Tom'},
    {id: 2, name: 'Jerry'},
]

Solution #1

You can make a custom component for that like this

const VirtualizedList = ({children}) => {
    return (
        <FlatList
            data={[]}
            keyExtractor={() => "key"}
            renderItem={null}
            ListHeaderComponent={
                <>{children}</>
            }
        />
    )
}

then use this VirtualizedList as parent component:

...
return (
    <VirtualizedList>
         <FlatList
           data={data}
           keyExtractor={(item, index) => item.id + index.toString()}
           renderItem={_renderItem}
         />
         <AnyComponent/>
    </VirtualizedList>
)

Solution #2

If you use FlatList inside the ScrollView it gives warning which is annoying, so you can use array's map property, like this -

NOTE: It is not recommended way to show list. If you have small amount of that then you can use it that's totally fine, but if you want to show a list which get data from api and have lot's of data then you can go with other solutions. if you use map with large data then it affect your app performance

<ScrollView>
    {data.map((item, index) => (
        <View key={index}>
           <Text>{item.name}</Text>
        </View>
    ))}
</ScrollView>

Solution #3

if you make your FlatList horizontal (as per your need) then also warning will disappear

<ScrollView>
    <FlatList
       data={data}
       keyExtractor={(item, index) => item.id + index.toString()}
       horizontal={true}
    />
</ScrollView>

Solution #4

you can add header and footer component

In ListHeaderComponent and ListFooterComponent you can add any component so you don't need parent ScrollView

<FlatList
   data={data}
   keyExtractor={(item, index) => item.id + index.toString()}
   ListHeaderComponent={headerComponent}
   ListFooterComponent={footerComponent}
   ListEmptyComponent={emptyComponent}
   ItemSeparatorComponent={separator}
/>

// List components
const headerComponent = () => (
    <View>
       <Header/>
       <Any/>
    </View>
)
const footerComponent = () => (
    <View>
       <Footer/>
       <Any/>
    </View>
)
const emptyComponent = () => (
    <View>
       <EmptyView/>
       <Any/>
    </View>
)
const separator = () => (
    <View style={{height: 0.8, width: '100%', backgroundColor: '#fff'}} />
)

The warning appears because ScrollView and FlatList share the same logic, if FlatList run inside ScrollView, it's duplicated

By the way SafeAreaView doesn't work for me, the only way to solve is

<ScrollView>
    {data.map((item, index) => {
        ...your code
    }}
</ScrollView>

The error disappears

Looking at the examples in docs I've changed container from:

<ScrollView>
    <FlatList ... />
</ScrollView>

to:

<SafeAreaView style={{flex: 1}}>
    <FlatList ... />
</SafeAreaView>

and all those warnings disappeared.

In my case, I needed to have FlatLists nested in a ScrollView because I am using react-native-draggable-flatlist to move ingredients and steps around in a recipe.

If we read the warning properly, it says that we should use another VirtualizedList-backed container to nest our child FlatList in. What I did is:

 /* outside the component */
const emptyArry = []

/* render */
 <FlatList
    scrollEnabled={false}
    horizontal
    data={emptyArray}
    ListEmptyComponent=(<DraggableList />)
  />

No more warning, and I think this is the pattern recommended by the warning.

<ScrollView horizontal={false} style={{width: '100%', height: '100%'}}>
   <ScrollView horizontal={true} style={{width: '100%', height: '100%'}}>
      <FlatList ... />
   </ScrollView>
</ScrollView>

Below code works perfectly for me to disable annoying error:

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.

React Native 0.68.2

  <ScrollView horizontal={false} style={{flex: 1}}>
    <ScrollView
      horizontal={true}
      contentContainerStyle={{width: '100%', height: '100%'}}>
      <FlatList ... />
    </ScrollView>
  </ScrollView>

I tried some ways to solve this, including ListHeaderComponent or ListFooterComponent, but it all didn't fit for me.

layout I wanted to achieve is like this, and I wanted to get scrolled in once.

<ScrollView>
  <View>I'm the first view</View>
  <View>I'm the second view</View>
  <MyFlatList />
</ScrollView>

First I want to say thanks to this issue and comments, which gave me bunch of ideas.

I was thinking of ListHeaderComponent places above the Flatlist, but since my Flatlist's direction was column, the header I wanted to place went on the left of the Flatlist :(

Then I had to try on VirtualizedList-backed thing. I just tried to pack all components in VirtualizedList, where renderItems gives index and there I could pass components conditionally to renderItems.

I could have worked this with Flatlist, but I haven't tried yet.
Finally it looks like this.

<View>
  <Virtualizedlist
    data={[]}
    initialNumToRender={1}
    renderItem={(props)=>{
      props.index===0 ? (1st view here) : props.index===1 ? (2nd view here) : (my flatlist)
    }}
    keyExtractor={item => item.key}
    getItemCount={2}
    getItem={ (data, index) => {
      return {
        id: Math.random().toString(12).substring(0),
      }
    }}
  />
</View>

(inside which lazyly renders↓)
  <View>I'm the first view</View>
  <View>I'm the second view</View>
  <MyFlatList />  

and of course able to scroll the whole screen.

As @Brahim stated above, setting the horizontal property to true seem to resolve the issues for a FlatList embedded in a ScrollView.

So I faced the same problem while using a picker-based component inside <ScrollView> and the one thing that helped me solve the problem was adding keyboardShouldPersistTaps={true} inside the <ScrollView> as a prop.

This is my code snippet.

<ScrollView keyboardShouldPersistTaps={true}> 
      <SelectionDD studentstatus={studentStatus}/>
      <SearchableDD collegeNames={collegeNames} placeholder='University'/>
</ScrollView>

Without hiding YellowBox you still can implement scroollable view inside scrollable view. You can use this library. It replace the default Scrollview from React Native.

This may help someone down the line, be sure you to check how your components are nested. Removing the ScrollView from the top component fixed the issue.

I ran into this issue because I had two components nested like this essentially:

Component 1

<ScrollView>
   <OtherStuff />

   <ListComponent />
</ScrollView>

My second component 'ListComponent' had a FlatList already wrapped with SafeAreaView.

<SafeAreaView style={styles.container}>
    <FlatList
        data={todoData}
        renderItem={renderItem}
        ItemSeparatorComponent={() => <View style={styles.separator} />}
        keyExtractor={item => item.id.toString()}
    />
</SafeAreaView>

In the end I replaced the ScrollView from the first component with a View instead.

I was having this issue using a scrollview as parent view, and nesting a SelectBox from react-native-multi-selectbox package. I was able to solve this by adding listOptionProps={{nestedScrollEnabled: true}} like this:

<ScrollView>
  <SelectBox
    label="Select single"
    options={serverData}
    listOptionProps={{nestedScrollEnabled: true}}
    value={input.elementSelected}
    onChange={event =>
      inputHandlerLang('elementSelected', event, key)
    }
    hideInputFilter={false}
  />
</ScrollView>

the error still present but scrolling within SelectBox works as well as within the parent scrollview. I also do have to suppress the error with LogBox. I don't know if there are any drawbacks to this but I'll try to test this more.

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>
    }
/>

This worked for me (as a bit of a hack). Use a FlatList with empty data and null renderItem props instead of using a ScrollView

const emptyData = [];

const renderNullItem = () => null;

const App = () => {
  const ListFooterComponent = (
    <FlatList ... />
  );

  return (
    <SafeAreaView>
      <FlatList
        data={emptyData}
        renderItem={renderNullItem}
        ListFooterComponent={ListFooterComponent}
      />
    </SafeAreaView>
  );
};

If you use ScrollView and FlatList together you'll get inconsistent scroll behaviour. So just remove ScrollView and use FlatList in a View.

<View flex={1}>
<FlatList 
    data={list}
    renderItem={({ item }) => this.renderItem(item) }
    keyExtractor={item => item.id}
    />
</View>

I have two Flatlist; each of them has many Item also has a feature to collapse and expand. Because of that, I can't use SafeAreaView.

I saw another solution and found a new way.

I define one Flatlist in the core component ( without Scrollview) and render each Flatlist with a map function inside ListHeaderComponent and ListFooterComponent.

 <View style={{flex: 1}}>
    <FlatList
        style={{backgroundColor: 'white'}}
        refreshing={loading}
        onRefresh={() => sample()}
        ListHeaderComponent = {
          <View>
             {collapse/expandComponent}
             {this.state.sample1&& content1.map((item, index) => this.renderList1(item,index))}
          </View>
        }
        ListFooterComponent = {
          <View>
            {collapse/expandComponent}
            {this.state.sample2 && content2.map((item, index) => this.renderlist2(item,index))}
          </View>
        }
      />
  </View>
import React from 'react';
import { FlatList, ScrollViewProps } from 'react-native';

export const ScrollView: React.FC<ScrollViewProps> = props => {
  return (
    <FlatList
      {...props}
      data={[]}
      renderItem={() => null}
      ListHeaderComponent={() => (
        <React.Fragment>{props.children}</React.Fragment>
      )}
      ListEmptyComponent={null}
      keyExtractor={() => 'blank'}
    />
  );
};

This will essentially work exactly like a ScrollView except without this error.

Actually as I know, using nested VirtualizedLists, caused always performance issues, just the warning to that issue is new. I tried everything I found on the internet, non of them helped. I use now ScrollView or when you just have a normall View with maxHeight then you will be able to scroll if the content-height is bigger then the maxHeight of you View. So:

<ScrollView>
   {items.map((item, index) =>
       <YourComponent key={index} item={item} />
   )}
</ScrollView>

Or just:

<View style={{maxHeight: MAX_HEIGHT}}>
    {items.map((item, index) =>
       <YourComponent key={index} item={item} />
    )}
</View>

This error disappeared because of using FlatList inside ScrollView. You can write like the following code.

<SafeAreaView style={styles.container}>
            <View style={styles.container}>
              <View>
                <Header />
              </View>

                {(list.length == 0) &&
                  <View style={{flex:1, margin: 15}}>
                    <Text style={{textAlign: 'center'}}>No peripherals</Text>
                  </View>
                }
                <FlatList 
                  data={list}
                  renderItem={({ item }) => this.renderItem(item) }
                  keyExtractor={item => item.id}
                />
            </View>
          </SafeAreaView>

You can add horizontal=True and contentContainerStyle={{ width: '100%' }} to the ScrollView parent.

<ScrollView
  style={styles.collaborators}
  contentContainerStyle={{ width: '100%' }} <-- 
  horizontal <--
>
  <FlatList
    data={list?.slice(0, 10) || []}
    keyExtractor={item => item.cc}
    ItemSeparatorComponent={Separator}
    renderItem={({ item }) => (
      <Collaborator name={item.name} cc={item.cc} />
    )}
  />
</ScrollView>

I had the same issue, and just got rid of it by removing the ScrollView around the FlatList. Because by default FlatList provides Scroll Functionality based on the length of content that it renders.

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