Stage 2 · Lesson 7 of 10
FlatList for long lists
A ScrollView draws all its children at once. That is fine for a form and slow for a feed. draws only the items near the screen and reuses as you scroll.
It takes data, a renderItem function and a keyExtractor that returns a stable id for each item. Use SectionList for grouped data. Keep renderItem cheap and memoise the row component, so it only redraws when its data changes.
Add onEndReached to load more pages, and refreshing plus onRefresh for pull to refresh. For heavy lists, Shopify's is a popular drop-in with better recycling. For images, expo-image adds caching and placeholders.
Common trapmapping a large array inside a ScrollView.
A question to check yourself, an AI practice session and 1 cheat sheet entry come with the full roadmap. Unlock
Resources for this stage
Start with· follow one of these
- GuideFreeExpo Documentation
Expo
The Expo tutorial builds a small app you run on your own phone
- GuideFreeReact Documentation
Meta
"Describing the UI" and "Adding interactivity" cover the React you need