How to start with React Native as ReactJS developer?

Recently, I spoke at React Nexus on "Accessibility and TV Apps." One question I kept getting was: "As a ReactJS developer, how easy is it to start with React Native?"

In short, for a ReactJS developer, starting with React Native would be easy.

In this blog, I am going to share the five concepts of ReactJS, ReactJS developers can use in React Native.

1. Components

In React Native, you will create components similarly to how you do in ReactJS. The concepts and best practices remain the same.

In the below code, you can see React Native component syntax is similarly like the ReactJS

import React from 'react';
import { View, Text } from 'react-native';

const GreetingComponent = () => {
  return (
    <View>
      <Text>Hello, Neha!</Text>
    </View>
  );
};
export default GreetingComponent;

2. Props and state

In React Native, props and state work the same way as in ReactJS. To communicate between components, you will use props. To update values, you will use state.

In the below code of react native, we are using props name similarly like ReactJS.

import React from 'react';
import { View, Text } from 'react-native';

const GreetingComponent = ({ name }) => {
  return (
    <View>
      <Text>Hello, {name}!</Text>
    </View>
  );
};
export default GreetingComponent;

3. Hooks

Just like in ReactJS, you can use all the hooks in React Native, such as useState(), useMemo(), useEffect(), etc. Additionally, you can create your own custom hooks.

In the below code of React Native, we are using useState() similarly like ReactJS

import React, { useState } from 'react';
import { View, Text, Button, StyleSheet } from 'react-native';

const GreetingComponent = () => {
  const [name, setName] = useState('John');

  const changeName = () => {
    setName('Jane');
  };

  return (
    <View style={styles.container}>
      <Text>Hello, {name}!</Text>
      <Button title="Change Name" onPress={changeName} />
    </View>
  );
};

export default GreetingComponent;

4. Testing

If you are a fan of the React Testing Library, the good news is you can use the same library for testing in React Native.

import React from 'react';
import { render, fireEvent } from '@testing-library/react-native';
import GreetingComponent from './GreetingComponent';

test('it renders correctly and changes name on button press', () => {
  // Render the component
  const { getByText } = render(<GreetingComponent />);

  // Assert initial state
  expect(getByText('Hello, John!')).toBeTruthy();

  // Find the button and simulate a press
  const button = getByText('Change Name');
  fireEvent.press(button);

  // Assert that the name has changed
  expect(getByText('Hello, Jane!')).toBeTruthy();
});

5. JSX

In React Native, there are a handful of components that can be used to create views in JSX. However, in ReactJS, you can use any valid HTML DOM elements.

In the below code of React Native, View, and Text are the React Native components. These components are used to create the view of the app.

import React from 'react';
import { View, Text } from 'react-native';

const GreetingComponent = () => {
  return (
    <View>
      <Text>Hello, Neha!</Text>
    </View>
  );
};
export default GreetingComponent;

Happy Learning!!

Neha Sharma @hellonehha