React Native FlatList – ListView in React Native

React Native FlatList

This is an example to show the Use of FlatList Component in React Native. React Native FlatList is a simple ListView. It is among the simple but mostly used components. Here is the example of FlatList which will be helpful for you to understand how to use it. You can also check SectionList example for the Section list.

To Import FlatList in Code

import { FlatList} from 'react-native'

Render FlatList Using

<FlatList
    data={
        Data To Be Set in List
    }
    ItemSeparatorComponent={
        An Separator View
    }
    renderItem={({ item }) =>
        (Single Item View)
    }
/>

In this example, We will make a simple list that will have A to Z as items and will show an alert with the item id and name while clicking on the single item of the FlatList. So let’s get started.

To Make a React Native App

Getting started with React Native will help you to know more about the way you can make a React Native project. We are going to use react native command line interface to make our React Native App.

If you have previously installed a global react-native-cli package, please remove it as it may cause unexpected issues:

npm uninstall -g react-native-cli @react-native-community/cli

Run the following commands to create a new React Native project

npx react-native init ProjectName

If you want to start a new project with a specific React Native version, you can use the --version argument:

npx react-native init ProjectName --version X.XX.X

Note If the above command is failing, you may have old version of react-native or react-native-cli installed globally on your pc. Try uninstalling the cli and run the cli using npx.

This will make a project structure with an index file named App.js in your project directory.

Code

Open App.js in any code editor and replace the code with the following code

App.js

//React Native FlatList
//https://aboutreact.com/react-native-flatlist/

//import React in our code
import React, {useState} from 'react';

//import all the components we are going to use
import {
    FlatList,
    View,
    Text,
    SafeAreaView,
    StyleSheet
} from 'react-native';

const dummyArray = [
  {id: '1', value: 'A'},
  {id: '2', value: 'B'},
  {id: '3', value: 'C'},
  {id: '4', value: 'D'},
  {id: '5', value: 'E'},
  {id: '6', value: 'F'},
  {id: '7', value: 'G'},
  {id: '8', value: 'H'},
  {id: '9', value: 'I'},
  {id: '10', value: 'J'},
  {id: '11', value: 'K'},
  {id: '12', value: 'L'},
  {id: '13', value: 'M'},
  {id: '14', value: 'N'},
  {id: '15', value: 'O'},
  {id: '16', value: 'P'},
  {id: '17', value: 'Q'},
  {id: '18', value: 'R'},
  {id: '19', value: 'S'},
  {id: '20', value: 'T'},
  {id: '21', value: 'U'},
  {id: '22', value: 'V'},
  {id: '23', value: 'W'},
  {id: '24', value: 'X'},
  {id: '25', value: 'Y'},
  {id: '26', value: 'Z'},
];

const App = () => {
  const [listItems, setListItems] = useState(dummyArray);

  const ItemView = ({item}) => {
    return (
      // FlatList Item
      <View>
        <Text
          style={styles.item}
          onPress={() => getItem(item)}>
          {item.value}
        </Text>
      </View>
    );
  };

  const ItemSeparatorView = () => {
    return (
      // FlatList Item Separator
      <View
          style={{
              height: 0.5,
              width: '100%',
              backgroundColor: '#C8C8C8'
          }}
      />
    );
  };

  const getItem = (item) => {
    //Function for click on an item
    alert('Id: ' + item.id + ' Value: ' + item.value);
  };

  return (
    <SafeAreaView style={{flex: 1}}>
      <View style={styles.container}>
        <FlatList
          data={listItems}
          //data defined in constructor
          ItemSeparatorComponent={ItemSeparatorView}
          //Item Separator View
          renderItem={ItemView}
          keyExtractor={(item, index) => index.toString()}
        />
      </View>
    </SafeAreaView>
  );
};

const styles = StyleSheet.create({
  container: {
    justifyContent: 'center',
    flex: 1,
    marginLeft: 10,
    marginRight: 10,
    marginBottom: 10,
    marginTop: 30,
  },
  item: {
    padding: 10,
    fontSize: 18,
    height: 44,
  },
});

export default App;

To Run the React Native App

Open the terminal again and jump into your project using.

cd ProjectName

1. Start Metro Bundler

First, you will need to start Metro, the JavaScript bundler that ships with React Native. To start Metro bundler run following command

npx react-native start

Once you start Metro Bundler it will run forever on your terminal until you close it. Let Metro Bundler run in its own terminal. Open a new terminal and run the application.

2. Start React Native Application

To run the project on an Android Virtual Device or on real debugging device

npx react-native run-android

or on the iOS Simulator by running (macOS only)

npx react-native run-ios

Download Source Code

Output Screenshot

Output in Online Emulator

This is how you can use FlatList component in React Native. If you have any doubts or you want to share something about the topic you can comment below or contact us here. There will be more posts coming soon. Stay tuned!

Hope you liked it. 🙂