Vidal Health Insurance Interview Questions and Answers

SOLID principles are a set of five design principles that help in creating maintainable and scalable software applications.

• S - Single Responsibility Principle (SRP)

• O - Open-Closed Principle (OCP)

• L - Liskov Substitution Principle (LSP)

• I - Interface Segregation Principle (ISP)

• D - Dependency Inversion Principle (DIP)

MVVM stands for Model-View-ViewModel, an architectural pattern used in software development.

• MVVM separates the user interface from the business logic and data access layers.

• Model represents the data and business logic, View represents the UI, and ViewModel acts as a mediator between the two.

• ViewModel exposes data and commands to the View, and communicates with the Model to retrieve and save data.

• MVVM is commonly used in Android development with frameworks like Android Archite...read more

Android Framework is a set of APIs and tools provided by Android to develop applications for Android devices.

• It provides a set of pre-built components for building mobile applications.

• It includes libraries for UI design, data storage, networking, and more.

• Developers can use Android Framework to create apps for smartphones, tablets, wearables, and other devices.

• Examples of Android Framework components include Activities, Fragments, Services, Content Providers, and Broadcast Re...read more

Room is an abstraction layer over SQLite to allow for more robust database access while harnessing the full power of SQLite.

• Room is a part of Android Architecture Components.

• It provides compile-time verification of SQL queries.

• It simplifies database operations by eliminating boilerplate code.

• It supports LiveData and RxJava for reactive programming.

• It allows for easy migration of database schema.

• It provides a clean API for database transactions.

• It supports relationships betwee...read more

A Builder class is used to create objects with a large number of optional parameters.

• Builder class is a creational design pattern.

• It separates the construction of a complex object from its representation.

• It allows you to create different variations of an object while avoiding constructor pollution.

• It has a fluent interface that allows you to chain method calls together.

• Example: StringBuilder in Java.

Coroutines and RxJava are both used for asynchronous programming in Android development.

• Coroutines are a lightweight solution for asynchronous programming that allow for easy cancellation and error handling.

• RxJava is a reactive programming library that uses Observables and Observers to handle asynchronous events.

• Both Coroutines and RxJava can be used to simplify complex asynchronous code and improve app performance.

• Coroutines are built into Kotlin, while RxJava requires an ad...read more

Activity lifecycle refers to the series of states an activity goes through during its lifetime in an Android app.

• onCreate() - activity is created

• onStart() - activity becomes visible to the user

• onResume() - activity is interacting with the user

• onPause() - activity is partially visible but still running

• onStop() - activity is no longer visible to the user

• onDestroy() - activity is being destroyed