React native: How to make horizontal scroll but data is divided to 4 rows - react-native

Question

I need to scroll my items horizontally but my data is divided to 4 rows every row contain 4 items. and I can scroll horizontally so the next 16 item come to the screen.
when using numColumns={4} it works if
horizontal={false}
but with
horizontal={true}
I can't specify numColumns attr.
Should I use SectionList instead of FlatList ?
and how it could be implemented ?
let items = [
{ id: 1, title: '1', price: '20' },
{ id: 2, title: '2', price: '16' },
{ id: 3, title: '3', price: '92' },
{ id: 4, title: '4', price: '93' },
{ id: 5, title: '5', price: '20' },
{ id: 6, title: '6', price: '16' },
{ id: 7, title: '7', price: '92' },
{ id: 8, title: '8', price: '93' },
{ id: 9, title: 'Grilled Steak', price: '20' },
{ id: 10, title: 'Pappas', price: '16' },
{ id: 11, title: 'Ciccione', price: '92' },
{ id: 12, title: 'Gyros Melt', price: '93' },
{ id: 13, title: 'Grilled Steak', price: '20' },
{ id: 14, title: 'Pappas', price: '16' },
{ id: 15, title: 'Ciccione', price: '92' },
{ id: 16, title: 'Gyros Melt', price: '93' },
];
<FlatList
keyExtractor={item => item.id}
data={items}
horizontal
numColumns={4}
renderItem={({ item }) => <Text>{item.title}</Text>}
/>

Answer 1

I have the same issue with same scenario. making group data is quite a bad practice in case you have long array. so I play with styles of flatlist and I was successful. following is my code if you can take advantage out of it:
<ScrollView showsHorizontalScrollIndicator={false} horizontal={true} style={styles.flatListContainer}>
<FlatList
showsHorizontalScrollIndicator={false}
data={item.items}
numColumns={4}
renderItem={_showData}
columnWrapperStyle={styles.flatListColumnWraper}
keyExtractor={(item) => item.key}
style={styles.flatListDataContainer}
scrollEnabled={false}
contentContainerStyle={
styles.flatListContentContainerStyle
}
/>
</ScrollView>
flatListContainer: {
marginTop: height(2),
height:height(60),
paddingVertical:height(2)
},
flatListDataContainer: {
alignSelf: 'center',
},
flatListContentContainerStyle: {
alignSelf: 'center',
flexDirection: 'row',
justifyContent: 'space-evenly',
},
flatListColumnWraper:{
flexDirection: 'column',
},

Answer 2

Unfortunately FlatList doesn't support a number of columns when it is horizontal.
https://facebook.github.io/react-native/docs/flatlist#numcolumns
Multiple columns can only be rendered with horizontal={false} and will
zig-zag like a flexWrap layout. Items should all be the same height -
masonry layouts are not supported.
However, you could group your data so that for every cell in a horizontal FlatList 4 items are rendered.
let items = [
[ { id: 1, title: '1', price: '20' },
{ id: 2, title: '2', price: '16' },
{ id: 3, title: '3', price: '92' },
{ id: 4, title: '4', price: '93' } ],
[ { id: 5, title: '5', price: '20' },
{ id: 6, title: '6', price: '16' },
{ id: 7, title: '7', price: '92' },
{ id: 8, title: '8', price: '93' } ],
[ { id: 9, title: 'Grilled Steak', price: '20' },
{ id: 10, title: 'Pappas', price: '16' },
{ id: 11, title: 'Ciccione', price: '92' },
{ id: 12, title: 'Gyros Melt', price: '93' } ],
[ { id: 13, title: 'Grilled Steak', price: '20' },
{ id: 14, title: 'Pappas', price: '16' },
{ id: 15, title: 'Ciccione', price: '92' },
{ id: 16, title: 'Gyros Melt', price: '93' } ]
];
Then update your renderItem so that it handles the increased input, something like this.
renderItem = ({item}) => {
return item.map(i => <Text>{i.title}</Text>)
}