Top 45+ React Native Interview Questions 2023

It sends the request to the XHR back-end, which is responsible for a processing network request. In React native, the StyleSheet.create() ensures that the values are immutable and opaque. They are used to send the style only once through the bridge to avoid passing a new style object.

All node_modules, as any real javascript library, would run fine if they don’t rely upon Node.js run-time modules or web-specific intentions. There is no defined way to test the compatibility of any node_modules. React Component is either a class or a function which accepts input data, and returns React element.

React Native Basic Interview Questions

Since React Native is essentially javascript, It is also single-threaded. In its rendering process, rather than have multiple processes occur at the same time , other components have to wait when one component is being rendered. React Router is a routing library https://wizardsdev.com/ build over React, this library was built to enable developers to add new flows and screens in the applications. Redux helps developers build web applications that perform consistently and are easy to test. It also includes live code editing and debugging tools.

Redux is a predictable state container for JavaScript apps. It helps write applications that run in different environments. This means the entire data flow of the app is handled within a single container while persisting previous state. We do not need to develop different applications for different platforms.

What are Virtual DOMs and how do they work?

Apart from this, ReactJS is a platform-independent programming language whereas ReactNative is platform-dependent. JSX is a ReactJS extension that enables developers to write JS Code that looks identical to HTML. It makes the blend of JS and HTML easy to understand. Learn about the key requirements, duties, responsibilities, and skills that should be in a react.js developer job description. Custom financial index investing service development Powerful data science project for custom investing indexes for the financial and insurance industries. Data pipeline for direct indexing service that is 7.5 times more effective…

The Virtual DOM will re-render the UI if our underlying data changes. The discrepancies between other DOM representations and Virtual DOM representations will then be counted, and the real DOM will be updated as a result. Render Props pattern is to share data and functionality between components without repeating code. Besides sharing the data and functionality of the shared component, render props enabled developer to have the full control of the component rendering.

How do you install and create a React Native application?

It is one of the most interesting react.js senior developer interview questions. If we are talking about React, then synthetic events work just like regular web browser events. Let’s consider basic interview questions on react.js and topics that will be useful for interviewing beginners who just have started their careers. They mainly relate to definitions, comparisons, and yes / no situations. They are necessary only to test the essential knowledge of the developer without technical tasks. We will describe what React is, why people like to work with it and much more.

• Say goodbye to finding other apps that might use similar code.
• Flux is very important since it was developed by Facebook along with React.
• Users interact with mobile apps mainly through touch.
• A React Native interview may also include questions regarding a person’s social and life abilities.
• It’s recommended to use async calls for component initialization or an external API call in componentDidMount() method.

The language used in React Native is Java for Android applications and Objective-C/Swift for iOS apps. Here, we are going to create a Text component with state data. The content of the Text component will be updated whenever we click on it. The event onPress calls the setState function, which updates the state with “myState” text. Snapshot testing is a type of “output comparison” or “golden master” testing.

Mention some of the best UI components in React Native.

React Native storage is a simple, unencrypted, asynchronous, persistent system, which stores the data globally in the app. React Native provides AsyncStorage class to store data globally. Using the AsyncStorage class, we need to have a data backup and synchronization class. It is because data saved on the device is not permanent and not encrypted.

Install the latest SDK version which is compatible with the latest version of react-native in the app.json file. Hope you have no doubts about this ReactJS interview questions article, in case of any difficulty, please leave your problems in the section below. Enables multiple views in a single application by defining multiple routes in the React application. It maintains consistent structure and behavior and is used to develop single-page web applications.

Upgrade your project files by running the following command. ListView is a core component of React Native, which contains a list of items and displays in vertical scrollable lists. They are used to identify which items have changed, updated, or deleted from the lists.

Languages that compile to JavaScript are generally compatible with React Native. React Native uses Babel to transform JavaScript into a form that is consumable by the native OS’s JavaScript runtime, using the react-native Babel plugin. As long as Babel can compile your JavaScript, and your code does not rely on web- or Node.js-specific dependencies, it will run in React Native. InteractionManager is very important because React Native has two threads.

ReactJS uses something called Virtual DOM. This is a kind of simplified copy of React HTML texts. Moreover, it is also a representation of the real DOM. For example, when it comes to web development, the DOM is used to represent HTML texts. According to the interviewer, the answer to this question is 4. I think you can now understand the standard of this company. What I have a problem with is the task that we were supposed to complete within 8hrs.

It is very hard to find that there are components available, which support both. But, it should be easy to figure out that the given components are made for React Native or not. Thus, it makes clear that all components are not usable in the React Native. Create smaller APK files for specific CPU architectures. When you do this, users of your application will automatically receive an APK file that matches their phone architecture. This eliminates the need to store JSCore binaries that support multiple architectures and therefore reduces the size of the application.

EWalletBankingEdTech The global education technology market size is expected to reach USD 318.8 billion by the year 2027. React helps developers divide UIs into multiple components, but doesn’t have a specific way to keep track of state data. Redux is a library that compliments React by providing a stable way to track this data. React uses this copy to determine what parts of the actual DOM need to change based on a user’s action. React then takes the change date from the Virtual DOM and selectively updates the actual DOM . Over time, this leads to significant performance improvements for the website or application.

Single Source of Truth is linked with Redux, it is because Redux stores all the state information of an application. The store component contains all information React Native Developer job related to different states, it uses a single state tree to store all that information. These props are passed from Parent to Child components.

How can React Native integrate more features on the existing app?

By using JSX, we can write HTML structures in the same file that contains JavaScript code. You don’t have to use server-side rendering with React. This Answer makes it sound like you will always use server-side rendering in every React project.