Programming Tutorials

Introduction This code demonstrates a Jetpack Compose application that utilizes Room database to manage employee data. The application allows adding new employees, deleting existing ones, and clearing all data. It leverages ViewModel to manage the data state and provide a single source of truth for the UI. Breakdown The code is organized into several classes: MainActivity.kt : This is the main activity that sets the content of the app using a Composable function called MainContent . MainContent.kt : This composable function builds the UI for the app. It retrieves data from the ViewModel, displays the number of employees, and presents a list of employees. It also provides buttons for adding new employees and clearing all data. RoomSingleton.kt : This class defines a Room database named "roomdb" with a single entity - Employee . It provides a singleton instance using the getInstance method. Employee.kt : This data class represents an employee with an ID (Long) and a ...

Introduction This code demonstrates an Android application built with Jetpack Compose and Room Persistence Library. The application manages employee data, allowing users to add, update, and clear employee records. The code utilizes several key components: Jetpack Compose: A modern UI framework for building declarative and reactive user interfaces. Room: A persistence library that provides an abstraction layer for SQLite databases. ViewModel: A lifecycle-aware class that manages data for a UI component. Breakdown of the Code The code is divided into several files: MainActivity.kt: The main activity of the application. It sets up the content of the screen using setContent and utilizes EmployeeViewModel to manage employee data. RoomSingleton.kt: Defines a singleton class for accessing the Room database instance. RoomEntity.kt: Defines the data structure for an employee ( Employee ) with fields for ID and full name. RoomDao.kt: Defines the Data Access Object (DAO) inte...