TCS React Native Developer Interview Questions and Answers

The possible values of a and b that satisfy the equation a*b = 104.

• Possible values of a and b are (1, 104) and (104, 1).

• Factors of 104 are (1, 104), (2, 52), (4, 26), (8, 13).

A simple program that prints 'Hello, World!' in Java.

• Create a class with a main method.

• Use System.out.println() to print 'Hello, World!'.

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

Concurrency in Swift can be handled using Grand Central Dispatch (GCD) and Operation Queues.

• Use GCD to perform tasks concurrently by creating dispatch queues.

• Use Operation Queues to manage and execute multiple operations concurrently.

• Avoid race conditions by using serial queues or synchronization techniques like semaphores or locks.

iOS app distribution methods include App Store, Ad Hoc, Enterprise, and TestFlight.

• App Store distribution is for public release and requires Apple's review process.

• Ad Hoc distribution allows sharing apps with a limited number of devices.

• Enterprise distribution is for in-house apps within a company.

• TestFlight is for beta testing with external testers before App Store release.

Flatten an array without using inbuilt methods

• Use recursion to iterate through the array and flatten it

• Create a new array to store the flattened elements

• Check if each element is an array, if so, recursively call the function to flatten it