Book Image

Kotlin Programming Cookbook

By : Aanand Shekhar Roy, Rashi Karanpuria
Book Image

Kotlin Programming Cookbook

By: Aanand Shekhar Roy, Rashi Karanpuria

Overview of this book

The Android team has announced first-class support for Kotlin 1.1. This acts as an added boost to the language and more and more developers are now looking at Kotlin for their application development. This recipe-based book will be your guide to learning the Kotlin programming language. The recipes in this book build from simple language concepts to more complex applications of the language. After the fundamentals of the language, you will learn how to apply the object-oriented programming features of Kotlin 1.1. Programming with Lambdas will show you how to use the functional power of Kotlin. This book has recipes that will get you started with Android programming with Kotlin 1.1, providing quick solutions to common problems encountered during Android app development. You will also be taken through recipes that will teach you microservice and concurrent programming with Kotlin. Going forward, you will learn to test and secure your applications with Kotlin. Finally, this book supplies recipes that will help you migrate your Java code to Kotlin and will help ensure that it's interoperable with Java.
Table of Contents (21 chapters)
Title Page
Copyright and Credits
Packt Upsell
Contributors
Preface
Index

Reading data from database


Now that we have seen how to create a database and how to create tables, let's learn how to read from a database.

Getting ready

I'll be using Android Studio 3 to write code. You can get started by adding anko-sqlite dependencies to your project and creating a SQLite database with the Requests table in it by going through and implementing the Using SQLite database in Kotlin recipe in this chapter. By using the form we created in this recipe, add some data to your Requests table.

How to do it…

Let's take look at the given steps to understand how to read data from the database:

  1. Now, let's add a button to our existing layout from the first recipe; on clicking, it should retrieve all data from our Requests table. Check out the updated code, which is as follows, where I have added a button with a click listener on it:
class MainActivity : AppCompatActivity() {

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        MainActivityUI...