SKO Systems Interview Questions and Answers

Android has four main components: Activities, Services, Broadcast Receivers, and Content Providers.

• Activities: UI components that represent a single screen with a user interface.

• Services: Background components that perform long-running operations.

• Broadcast Receivers: Respond to system-wide broadcast announcements.

• Content Providers: Manage a shared set of app data that can be accessed by other apps.

MVVM is a design pattern that separates UI code from business logic using a ViewModel.

• MVVM stands for Model-View-ViewModel

• Model represents the data and business logic

• View represents the UI

• ViewModel acts as a mediator between the Model and View

• ViewModel exposes data and commands to the View

• MVVM helps in unit testing and maintainability

• Example: Android Architecture Components provide support for MVVM

Android supports various types of storage options for storing data.

• Internal Storage

• External Storage

• Shared Preferences

• SQLite Databases

• Network Connection

Fragments are reusable UI components in Android used to create flexible and dynamic user interfaces.

• Fragments allow for modularization of UI components

• They can be reused across multiple activities

• They can be added or removed dynamically at runtime

• They help in creating responsive UIs for different screen sizes

• Example: A news app can use a fragment to display a list of articles and another fragment to display the details

Constraint layout is preferred for its flexibility and efficiency.

• Allows for complex layouts with minimal nesting

• Supports responsive design and animations

• Reduces the need for nested layouts

• Improves performance by reducing layout hierarchy

• Easier to maintain and update layouts

• Compatible with Android Studio's Layout Editor

Service is a component in Android that runs in the background to perform long-running operations.

• Services can be started or bound to an activity

• They can run indefinitely or until they complete their task

• They can communicate with other components using intents or callbacks

Retrofit is a type-safe HTTP client for Android and Java.

• Retrofit simplifies the process of sending network requests and handling responses.

• It uses annotations to define API endpoints and request parameters.

• Retrofit also supports various data formats such as JSON, XML, and Protocol Buffers.

• It can be used with other libraries like OkHttp for better performance.

• Retrofit is widely used in Android development for consuming

Developed a social media app using Kotlin and MVVM architecture.

• Used Kotlin for coding the app

• Implemented MVVM architecture for better code organization

• Integrated Firebase for real-time database and authentication

• Used Glide library for image loading and caching

• Implemented RecyclerView for displaying posts and comments