The answer is to add the horizontal property set to true
.
Yeah now it’s described in the doc: https://reactnative.dev/docs/flatlist#horizontal
So obviously a FlatList is a Child of a ScrollView so he got the Horizontal Bool.
<FlatList
horizontal={true}
data={DATA}
renderItem={renderItem}
keyExtractor={(item) => item.id}
extraData={selectedId}
/>
Ciao