In React Native, the FlatList component's renderItem prop expects a callback function that returns a React Element. When using TypeScript, you may encounter a type error if the types do not match correctly.

To resolve the "type is not assignable" error, ensure that the type of the data provided to the FlatList component matches the expected type of the renderItem prop. Here's an example of how you can define the types correctly:

Assuming you have an array of items with a specific type, you can define the types for the data and the item in the following way:

tsx
import React from 'react'; import { FlatList, Text } from 'react-native'; // Define the type for each item in the data array type Item = { id: number; name: string; }; // Sample data array const data: Item[] = [ { id: 1, name: 'Item 1' }, { id: 2, name: 'Item 2' }, // Add more items here ]; const renderItem = ({ item }: { item: Item }) => { return <Text>{item.name}</Text>; }; const MyComponent: React.FC = () => { return <FlatList data={data} renderItem={renderItem} keyExtractor={(item) => item.id.toString()} />; }; export default MyComponent;

In this example, we define the Item type to represent each item in the data array. The renderItem function takes an object with a property item of type Item. When rendering the FlatList, we provide the data array and the renderItem function, and TypeScript will ensure that the types match correctly.

Ensure that the types of data, the renderItem function, and the expected item match correctly to avoid type errors with the FlatList component. If you are still facing issues, double-check your code and make sure the types are defined correctly for your specific use case.

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