This article lists the top 50 React Native interview questions and answers in the software development industy.
React Native is highly relevant in hiring software developers, especially those who specialize in mobile app development. With the increasing demand for mobile apps across industries, many companies are turning to React Native as a cost-effective and efficient way to build mobile apps for both iOS and Android platforms using a single codebase.
Therefore, developers with React Native skills are highly sought after by companies looking to develop or maintain mobile apps. Having experience with React Native can significantly increase a developer’s employability and job opportunities, as well as their earning potential.
Interview questions are questions that you will be asked by an interviewer during a job interview to assess a your qualifications, skills, experience, and suitability for a particular role. If you are applying for the role of a React Native developer, be rest assured that you will write a technical interview.
We have put together a list of the top 30 React Native interview questions that you might encounter in your technical interview.
const initialState = {
count: 0
}
function counterReducer(state = initialState, action) {
switch (action.type) {
case 'INCREMENT':
return { count: state.count + 1 };
case 'DECREMENT':
return { count: state.count - 1 };
default:
return state;
}
}
19. How do you install a React Native application?
To install and create a React Native application, follow these steps:
a. Install Node.js and npm on your computer if you haven’t already.
b. Install React Native CLI by running the following command in your terminal:
npm install -g react-native-cli
c. Create a new React Native project by running the following command in your terminal:
npx react-native init <project-name>
d. Navigate to the project directory by running the following command in your terminal:
cd <project-name>
e. Start the development server by running the following command in your terminal:
npx react-native start
f. Open a new terminal window and run the app on either iOS or Android by running one of the following commands:
npx react-native run-ios //For iOS
npx react-native run-android //For android
20. What are the limitations of React Native? React Native is still a relatively new framework and may not have all the features and capabilities of native app development. It may also have compatibility issues with certain devices or operating systems.
21. What is the difference between React Native and React Native Web? React Native Web is a library that allows developers to build web applications using React Native components. It is not a separate framework but rather an extension of React Native.
22. What is the Virtual DOM? The Virtual DOM is a lightweight copy of the actual DOM that allows React to update the user interface efficiently without having to redraw the entire page.
23. What is the lifecycle method in React Native? The lifecycle method is a set of methods that are called at different stages of a component’s life cycle, such as when it is created, updated, or destroyed.
24. What is the Flux architecture? Flux is an architecture pattern for building client-side web applications that allows developers to manage the flow of data through an application in a unidirectional manner.
25. What is the difference between React Native and Ionic? React Native is a framework for building cross-platform mobile applications using React, while Ionic is a framework for building hybrid mobile applications using HTML, CSS, and JavaScript.
26. What is the difference between React Native and Flutter? React Native is a framework for building cross-platform mobile applications using JavaScript and React, while Flutter is a framework for building native mobile applications using Dart.
27. What is the difference between a functional component and a class component in React? A functional component is a simpler and more concise way of defining a component using a function, while a class component is a more complex way of defining a component using a class.
Functional components are a simpler and more concise way of defining a component in React. They are defined as JavaScript functions that return JSX, which describes the user interface of the component.
Functional components don’t have a state or lifecycle methods, but they can use React Hooks to achieve similar functionality. For example, the useState() hook can be used to add state to a functional component, while the useEffect() hook can be used to perform side effects such as fetching data or updating the DOM.
Here’s an example of a simple functional component in React:
import React from 'react';
function Greeting(props) {
return <h1>Hello, {props.name}!</h1>;
}
export default Greeting;
In this example, the Greeting
component takes a name
prop and renders a greeting message using it. The props
argument is an object that contains all the props passed to the component.
Functional components are a great option for simple, stateless components that only need to render content based on their props. They are also easier to test and optimize than class components.
Class components are one of the ways to define a component in React. They are defined as classes that extend the React.Component
base class and have a render()
method that returns JSX describing the component’s user interface.
Class components can have a state that is managed using the setState()
method. They also have access to lifecycle methods, which allow them to perform actions at specific points in the component’s lifecycle, such as when it is mounted or updated.
Here’s an example of a simple class component in React:
import React from 'react';
class Counter extends React.Component {
constructor(props) {
super(props);
this.state = { count: 0 };
this.handleClick = this.handleClick.bind(this);
}
handleClick() {
this.setState({ count: this.state.count + 1 });
}
render() {
return (
<div>
<p>Count: {this.state.count}</p>
<button onClick={this.handleClick}>Increment</button>
</div>
);
}
}
export default Counter;
28. What is the difference between props and context? Props are external inputs to a component that are passed down from a parent component, while context is a way to pass data between components without having to pass props through every level of the component tree.
29. What is the difference between AsyncStorage and LocalStorage? AsyncStorage is a built-in storage system for React Native that allows developers to store data on the device, while LocalStorage.
There are many different ways to optimize an application. Let’s take a look at some of our options. We can:
These are some of the top React Native questions and answers that you can encounter in your technical interview. It is not advisable to cram these questions, but it’s important that you practice and understand them so that you can answer them in any given circumstance.
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