SectionList with Headers
Group items into sections with SectionList, render a sticky section header for each group, and customize the separator between items.
SectionList with Headers is a free React Native Academy lesson on CoddyKit — lesson 3 of 4. You can read the complete lesson below for free — then practise it hands-on in the browser with a built-in code editor and a 24/7 AI tutor. It is part of the React Native Academy learning path, one of 4 lessons in the course, and your progress syncs across the web and the CoddyKit app.
When to Use SectionList
SectionList is the React Native component for displaying grouped lists — data divided into sections, each with its own header. It is ideal for contacts lists sorted alphabetically, settings screens with grouped options, or e-commerce categories. Like FlatList, it virtualizes rendering for performance.
SectionList Data Format
SectionList expects its sections prop to be an array of section objects. Each section object must have a data array containing the items for that section. You also typically include a title or other metadata to render the section header.
const SECTIONS = [
{
title: 'A',
data: [
{ id: '1', name: 'Alice' },
{ id: '2', name: 'Andrew' },
],
},
{
title: 'B',
data: [
{ id: '3', name: 'Bob' },
{ id: '4', name: 'Beth' },
],
},
];Rendering Items with renderItem
The renderItem function in SectionList receives an object with the current item, its index within the section, and the section object itself. This gives you access to both the item data and the enclosing section's metadata in the same render call.
const renderItem = ({ item, section }) => (
<View style={styles.row}>
<Text>{item.name}</Text>
<Text style={styles.sectionLabel}>{section.title}</Text>
</View>
);Rendering Section Headers
Pass a renderSectionHeader function to display a header above each section. The function receives { section } — the current section object. Returning a View with a colored background makes the header stand out from the items below it.
const renderSectionHeader = ({ section }) => (
<View style={styles.sectionHeader}>
<Text style={styles.sectionTitle}>{section.title}</Text>
</View>
);
<SectionList
sections={SECTIONS}
renderItem={renderItem}
renderSectionHeader={renderSectionHeader}
keyExtractor={(item) => item.id}
/>Sticky Section Headers
By default, section headers scroll with the list. Set stickySectionHeadersEnabled to true to make headers stick to the top of the screen as you scroll past them — the same behavior you see in the iOS Contacts app. This is set to true by default on iOS and false on Android.
<SectionList
sections={SECTIONS}
renderItem={renderItem}
renderSectionHeader={renderSectionHeader}
keyExtractor={(item) => item.id}
stickySectionHeadersEnabled={true}
/>Section Footer with renderSectionFooter
Use renderSectionFooter to render content after the last item in each section. This is useful for showing a 'View all' link or a count of remaining items below a truncated group. The function receives the same { section } argument as renderSectionHeader.
const renderSectionFooter = ({ section }) => (
<TouchableOpacity>
<Text style={styles.viewAll}>
View all {section.data.length} {section.title} contacts
</Text>
</TouchableOpacity>
);Item Separators in SectionList
Like FlatList, SectionList supports ItemSeparatorComponent to render dividers between items within a section. SectionList also provides SectionSeparatorComponent to render a separator between the end of one section (or its footer) and the start of the next section's header.
const ItemSeparator = () => <View style={styles.separator} />;
const SectionSeparator = () => <View style={styles.sectionSeparator} />;
<SectionList
sections={SECTIONS}
renderItem={renderItem}
renderSectionHeader={renderSectionHeader}
keyExtractor={(item) => item.id}
ItemSeparatorComponent={ItemSeparator}
SectionSeparatorComponent={SectionSeparator}
/>A Full SectionList Example
Bringing it all together: define your sections data, provide renderItem and renderSectionHeader, set a keyExtractor, and optionally enable sticky headers. This pattern covers the majority of grouped list use cases in production apps.
import { SectionList, View, Text, StyleSheet } from 'react-native';
export default function ContactsScreen() {
return (
<SectionList
sections={SECTIONS}
keyExtractor={(item) => item.id}
renderItem={({ item }) => (
<View style={styles.row}><Text>{item.name}</Text></View>
)}
renderSectionHeader={({ section }) => (
<View style={styles.header}><Text style={styles.headerText}>{section.title}</Text></View>
)}
stickySectionHeadersEnabled
/>
);
}Building Data for SectionList from a Flat Array
Often your API returns a flat array. You need to group items by a common property before passing them to SectionList. Use Array.reduce to build a map, then convert it to the sections format. Sort the sections alphabetically for a predictable order.
function groupByFirstLetter(contacts) {
const map = contacts.reduce((acc, contact) => {
const letter = contact.name[0].toUpperCase();
if (!acc[letter]) acc[letter] = [];
acc[letter].push(contact);
return acc;
}, {});
return Object.keys(map).sort().map((key) => ({
title: key,
data: map[key],
}));
}Scrolling to a Specific Section
Use a ref on the SectionList and call scrollToLocation to jump to a specific item or section header. This is essential for alphabetic index bars (like the sidebar in iOS Contacts) where tapping a letter scrolls the list to that section.
const sectionListRef = useRef(null);
const scrollToSection = (sectionIndex) => {
sectionListRef.current?.scrollToLocation({
sectionIndex,
itemIndex: 0,
animated: true,
});
};
<SectionList ref={sectionListRef} sections={SECTIONS} ... />Performance Tips for SectionList
The same performance rules that apply to FlatList apply to SectionList. Stabilize renderItem and renderSectionHeader with useCallback. Avoid creating new objects inline in the sections prop on every render — memoize the processed sections data with useMemo.
const sections = useMemo(
() => groupByFirstLetter(contacts),
[contacts]
);
const renderItem = useCallback(({ item }) => (
<Row item={item} />
), []);Quick Check
Test your understanding of SectionList with headers from this lesson.
Lesson Recap
In this lesson you learned: SectionList sections prop takes an array of objects each with a data array, renderSectionHeader renders a title above each group, and stickySectionHeadersEnabled pins headers to the top as users scroll. Next up we build a complete Contacts List App combining SectionList, search, and pull-to-refresh.
Frequently asked questions
Is the “SectionList with Headers” lesson free?
Yes — the full text of “SectionList with Headers” is free to read here on the web, and the React Native Academy course includes 4 lessons in total. To practise it interactively (a built-in code editor and a 24/7 AI tutor) and unlock the rest of the React Native Academy course, upgrade to CoddyKit PRO.
What will I learn in “SectionList with Headers”?
Group items into sections with SectionList, render a sticky section header for each group, and customize the separator between items. You practise React Native Academy with hands-on code you run directly in the browser, and a 24/7 AI tutor answers your questions as you work through the lesson.
Do I need any experience to start React Native Academy?
No prior experience is required. React Native Academy on CoddyKit is structured for beginners through advanced learners; this is — lesson 3 of 4, so you can start here or from the beginning and move at your own pace.
How long does the “SectionList with Headers” lesson take?
Most CoddyKit lessons take about 5–10 minutes. Each one is bite-sized and interactive, so you make steady progress and pick up exactly where you left off across the web and the app.
Can I write and run code in this React Native Academy lesson?
Yes. Every React Native Academy lesson includes a built-in code editor, so you write and run real code right in your browser and get instant AI feedback — no local setup required.