BYLD Group Android Developer Interview Questions and Answers

I have created 10 projects. The most significant one is a fitness tracking app called FitTrack.

• Created 10 projects in total

• Most significant project is FitTrack - a fitness tracking app

• FitTrack allows users to track their workouts, set goals, and monitor progress

I have 3 years of experience with Flutter, 5 years with Java, and 2 years with Kotlin.

• 3 years of experience with Flutter

• 5 years of experience with Java

• 2 years of experience with Kotlin

Yes, Work Manager is a library used for managing background tasks in Android applications.

• Work Manager is part of Android Jetpack and provides a flexible way to schedule deferrable, asynchronous tasks.

• It handles tasks that need to run even if the app is in the background or not running.

• Work Manager takes care of task persistence, retries, and network constraints automatically.

• It is recommended for tasks that are not ti...read more

Stateful widgets maintain state that might change during the lifetime of the widget, while stateless widgets are immutable and do not change.

• Stateful widgets have a State object that can hold dynamic information and can be updated over time.

• Stateless widgets are immutable and their properties cannot change once they are initialized.

• Stateful widgets are used when the UI can change dynamically based on user interactions ...read more

Activity and Fragment have different life cycles in Android development.

• Activity life cycle includes onCreate, onStart, onResume, onPause, onStop, onDestroy

• Fragment life cycle includes onAttach, onCreate, onCreateView, onActivityCreated, onStart, onResume, onPause, onStop, onDestroyView, onDestroy, onDetach

• Activity can contain multiple fragments with their own life cycles

Grey errors in Flutter are compile-time errors, while red errors are runtime errors.

• Grey errors are compile-time errors that prevent the code from being compiled and run, such as syntax errors or type mismatches.

• Red errors are runtime errors that occur while the code is running, such as null pointer exceptions or out-of-bounds errors.

Coroutines in Kotlin are lightweight threads that help manage asynchronous tasks efficiently.

• Coroutines are more efficient than AsyncTask as they can handle multiple tasks concurrently without creating new threads.

• Coroutines are more flexible and easier to use compared to AsyncTask.

• Coroutines can be easily cancelled, unlike AsyncTask which can lead to memory leaks if not handled properly.

• WorkManager is recommended for ...read more

Reactive Programming is a programming paradigm that focuses on asynchronous data streams and the propagation of changes.

• Uses observables to handle data streams and propagate changes

• Emphasizes declarative programming and event-driven architecture

• Commonly used in frameworks like RxJava, RxJS, and Reactor

In Flutter, I use Provider package for state management. In native Android development, I use LiveData and ViewModel.

• In Flutter, use Provider package for managing state efficiently

• In native Android development, use LiveData and ViewModel to handle state changes

• Consider using Redux or MobX for more complex state management in Flutter

Native, Hybrid, and Cross Platform development differ in their approach to building mobile applications.

• Native development involves building apps specifically for a single platform using the platform's native programming languages and tools (e.g. Java/Kotlin for Android, Swift/Objective-C for iOS).

• Hybrid development uses web technologies like HTML, CSS, and JavaScript to build apps that can run on multiple platforms wi...read more

Yes, Kotlin supports native development for Android through the use of Kotlin/Native.

• Kotlin/Native allows developers to compile Kotlin code directly to native binaries, which can be used for Android development.

• It enables developers to write platform-specific code in Kotlin for Android apps.

• Kotlin/Native also supports interoperability with existing native code written in C or C++.

SOLID principles are a set of five design principles that help make software more maintainable, flexible, and scalable.

• S - Single Responsibility Principle: A class should have only one reason to change.

• O - Open/Closed Principle: Software entities should be open for extension but closed for modification.

• L - Liskov Substitution Principle: Objects of a superclass should be replaceable with objects of its subclasses withou...read more