Softlets React Native Developer Interview Questions and Answers

Sorting an array and using HOC components and Flux in React Native

• To sort an array, use the sort() method

• To use HOC components, create a higher-order function that returns a component

• To use Flux in React Native, install the flux package and create actions, stores, and a dispatcher

Answering questions related to Redux, props, hooks in React Native and its tools

• Redux is a state management library for JavaScript applications

• Props are short for properties and are used to pass data between components

• Hooks are functions that allow you to use state and other React features without writing a class

• React Native tools include Expo, React Native Debugger, and Xcode

• Expo is a set of tools and services for bui...read more

Functional components are stateless and use functional programming concepts, while class components are stateful and use object-oriented programming concepts.

• Functional components are simpler and easier to read and test.

• Class components have access to lifecycle methods and state.

• Functional components are preferred for simple UI components, while class components are preferred for complex UI components.

• Functional compon...read more

Yes, I have worked on native components.

• I have experience in creating custom native modules for React Native apps.

• I have integrated native libraries like Firebase, Google Maps, and Camera into React Native apps.

• I have used native UI components like TextInput, ScrollView, and FlatList in React Native apps.

• I have also worked with native modules for iOS and Android separately.

Hooks are functions that allow you to use state and other React features without writing a class.

• useState() - for managing state in functional components

• useEffect() - for performing side effects in functional components

• useContext() - for consuming context in functional components

• useReducer() - for managing complex state in functional components

• useCallback() - for memoizing functions in functional components

Hermes is a JavaScript engine optimized for React Native apps.

• Developed by Facebook to improve app startup time and reduce memory usage.

• Uses ahead-of-time compilation to convert JavaScript code into bytecode.

• Supports ES6 syntax and is compatible with most React Native libraries.

• Can be enabled in React Native projects by adding a single line to the configuration file.

Yes, I am familiar with the new architecture of React Native.

• The new architecture of React Native is based on Fabric, a C++ UI framework.

• It separates the UI rendering from the JavaScript thread, resulting in improved performance.

• It also introduces new features like TurboModules and JSI for better native module integration.

• The new architecture is being gradually rolled out in React Native releases.

• It requires some chang...read more

MVVM is a design pattern that separates the UI, business logic, and data layers in an iOS application.

• Model: Represents the data and business logic of the application.

• View: Represents the UI components of the application.

• ViewModel: Acts as a mediator between the Model and View, handling the presentation logic and data binding.

• Pros: Separation of concerns, easier to maintain and test, promotes reusability.

• Cons: Increase...read more

Multithreading in Swift allows for concurrent execution of tasks to improve performance and responsiveness.

• Use Grand Central Dispatch (GCD) for managing concurrent tasks

• Avoid blocking the main thread to prevent UI freezes

• Consider using Operation and OperationQueue for more complex task management