SectionList com cabeçalhos
Agrupe itens em seções com SectionList, renderize um cabeçalho fixo para cada grupo e personalize o separador entre os itens.
SectionList com cabeçalhos é uma aula grátis de React Native Academy no CoddyKit. Esta é a aula 3 de 4. Você pode ler a aula completa abaixo gratuitamente — depois pratica ao vivo no navegador com um editor de código integrado e um tutor de IA 24/7. Faz parte do caminho de aprendizado de React Native Academy, e seu progresso é sincronizado entre a web e o app CoddyKit. O curso de React Native Academy inclui 4 aulas no total.
Partes desta aula ainda não foram traduzidas e aparecem em inglês.
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.
Perguntas Frequentes
A aula “SectionList com cabeçalhos” é grátis?
Sim — o texto completo de “SectionList com cabeçalhos” é grátis para ler aqui na web. Para praticá-la interativamente (um editor de código integrado e um tutor de IA 24/7) e desbloquear o restante do curso de React Native Academy, atualize para CoddyKit PRO. O curso de React Native Academy inclui 4 aulas no total.
O que vou aprender em “SectionList com cabeçalhos”?
Agrupe itens em seções com SectionList, renderize um cabeçalho fixo para cada grupo e personalize o separador entre os itens. Você pratica React Native Academy com código prático que executa diretamente no navegador, e um tutor de IA 24/7 responde suas dúvidas enquanto trabalha na aula.
Preciso ter experiência prévia para começar React Native Academy?
Nenhuma experiência prévia é necessária. React Native Academy no CoddyKit é estruturado para alunos iniciantes até avançados, então você pode começar aqui ou desde o início e aprender no seu ritmo. Esta é a aula 3 de 4.
Quanto tempo leva a aula “SectionList com cabeçalhos”?
A maioria das aulas CoddyKit leva cerca de 5–10 minutos. Cada uma é compacta e interativa, então você faz progresso constante e retoma exatamente de onde parou entre web e app.
Posso escrever e executar código nesta aula de React Native Academy?
Sim. Cada aula de React Native Academy inclui um editor de código integrado, então você escreve e executa código real direto no navegador e recebe feedback de IA instantaneamente — nenhuma configuração local necessária.
Todas as aulas deste curso
- Dados de FlatList, renderItem e keyExtractor
- Deslizar para atualizar e carregar mais
- SectionList com cabeçalhos
- Criando um aplicativo de lista de contatos