Book Image

Android Studio 4.0 Development Essentials - Kotlin Edition

By : Neil Smyth
Book Image

Android Studio 4.0 Development Essentials - Kotlin Edition

By: Neil Smyth

Overview of this book

Kotlin as an Android-compatible programming language is becoming increasingly popular. Fully updated for Android Studio 4.0, this book will teach you the skills necessary to develop Android-based applications using Kotlin. Starting with the basics, this book outlines the steps necessary to set up Android development and testing environments, and goes on to introduce you to programming in Kotlin. You’ll practice Java to Kotlin code conversion and explore data types, operators, expressions, loops, functions, as well as the basics of OOP in Kotlin. You’ll then learn about Android architecture components and advanced topics, such as intents, touchscreen handling, gesture recognition, multi-window support integration, and biometric authentication. As you make progress, you’ll explore Android Studio 4.0’s key features, including layout editor, direct reply notifications, and dynamic delivery. You’ll also delve into Android Jetpack and create a sample app project using ViewModel, the Android Jetpack component. Finally, you will upload your app to Google Play Console and model the build process using Gradle. By the end of this Android book, you’ll be fully prepared to develop applications using Android Studio 4.0 and Kotlin.
Table of Contents (97 chapters)
97
Index

51.3 Configuring Start and End Constraints

With the activity_main.xml file loaded into the MotionLayout editor, make sure that the Motion Layout box (marked E in Figure 51-5 below) is selected, then delete the default TextView before dragging and dropping a Button view from the palette to the top left-hand corner of the layout canvas as shown in Figure 51-4:

Figure 51-4

With the button selected, use the Attributes tool window to change the id to myButton.

As outlined in the previous chapter, MotionLayout animation is primarily a case of specifying how a view transitions between two states. The first step in implementing animation, therefore, is to specify the constraints that define these states. For this example, the start point will be the top left-hand corner of the layout view. To configure these constraints, select the start constraint set entry in the editor window (marked A in Figure 51-5):

Figure 51-5

When the start box is selected, all constraint...