React Native Interview Questions – Set 04

What are the similarities between React and React Native?

The most common similarities between React and React Native are:

  • React Lifecycle Methods
  • React Components
  • React States and Props
  • Redux Libraries

What are the advantages of React Native?

React Native provides many advantages for building mobile applications. Some of the essential benefits of using React Native are given below:

  • Cross-Platform: It offers the facility to “Write once and run everywhere.” It is used to create apps for Android, iOS, and Windows platforms.
  • Performance: The code written in React Native is compiled into native code, which enables it for all operating systems to provide closer native appearance and functions in the same way on all platforms.
  • Community: React Native provides a large community of passionate developers who are always ready to help us to fix bugs, and issues occur at any instant.
  • Hot Reloading: Making a few changes in your app’s code immediately visible during development. If the business logic is changed, its reflection is live reloaded on screen.
  • Faster Development: React Native helps to develop apps fast. It uses a common language to build an app for Android, iOS, and Windows platforms, which gives speedier app deployment, delivery, and quicker time-to-market.
  • JavaScript: JavaScript knowledge is used to build native mobile apps.

List the users of React Native?

Today, thousands of React Native built-in apps are available in the market. Here is the list of users who uses React Native apps:

  • Facebook
  • Facebook Ads Manager
  • Instagram
  • F8
  • Airbnb
  • Skype
  • Tesla
  • Bloomberg
  • Gyroscope
  • Myntra
  • UberEats

What is meant by InteractionManager, and why it is Important?

The InteractionManager is a native module in React Native, which is responsible for differing the execution of a function until an interaction has finished. To handle this deferral, we need to call InteractionManager.runAfterInteractions(() => {…}).

The InteractionManager is important because React Native has two threads. One is JavaScript UI thread, which handles drawing updates to the screen, and the second thread used for all task, not on the UI thread. Since React Native has only one thread for making UI updates, it can get overloaded and drop frames, especially in navigation screen animations. So, developers use the InteractionManager to ensure that the function is executed after these animations occur. As a result, we do not drop frames on the UI thread.

What is the difference between React Native and Ionic?

The essential differences between React Native and Ionic are:

  • Ionic is a typical hybrid development framework. It mainly focuses on front-end user experience or UI interaction, which handles all the look and feel of your app. It is easy to learn and can integrate with other libraries or frameworks such as Angular, React, Cordova, etc. Its purpose is to write once and runs everywhere.
  • React Native is an open-source JavaScript framework developed by Facebook to build a cross-platform mobile app. It is used for developing a mobile application for iOS, Android, and Windows. React Native is the same as React, but it uses native components instead of using web components as building blocks. It targets mobile platforms rather than the browser. Its purpose is to learn once and write anywhere.

Which language is used in React Native?

The language used in React Native is Java for Android applications and Objective-C/Swift for iOS apps.

Why React Native use Redux?

Redux is a state container for JavaScript applications. It is a state management tool, which helps you to write applications that behave consistently, can run in a different environment, and are easy to test.

React Native use Redux because it allows developers to use one application state as a global state and interact easily with the state from any React component. It can combine with any framework or library.

What are animations in React Native?

The animation is a method in which images are manipulated to appear as moving objects. React Native animations allows you to add extra effects, which provide great user experience in the app. We can use it with React Native API, Animated.parallel, Animated.decay, and Animated.stagger.

React Native has two types of animation, which are given below.

  • Animated: This API is used to control specific values. It has a start and stops methods for controlling the time-based animation execution.
  • LayoutAnimated: This API is used to animate the global layout transactions.

What are the disadvantages of React Native?

Some of the big disadvantages of React Native for building mobile applications are given below:

  • React Native is still new and immature: React Native is a new framework in Windows, Android, and iOS programming languages. It is still in the improvement stage, which can have a negative impact on the apps.
  • Learning is tough: React Native cannot learn quickly, especially for a fresher in the app development field.
  • It Lacks the Security Robustness: React Native is an open-source JavaScript framework, which is fragile and creates a gap in the security robustness. When you are creating banking and financial apps where data is highly confidential, experts advise not to choose React Native.
  • It Takes More Time to Initialize: React Native takes a lot of time for initializing the runtime even if you are using the hi-tech gadgets and devices.
  • Existence is Uncertain: As Facebook develop this framework, its presence is uncertain since it keeps all the rights to kill off the project anytime. As the popularity of React Native rises, it is unlikely to happen.

Are all React components usable in React Native?

React web components use DOM elements (ex. div, h1, table, etc.) to display on UI. But, these components are not supported in React Native. You will need to find libraries or components which is made specifically for React Native. 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.