Book Image

Android Studio 3.5 Development Essentials - Java Edition

By : Neil Smyth
Book Image

Android Studio 3.5 Development Essentials - Java Edition

By: Neil Smyth

Overview of this book

Android applications have become an important part of our daily lives and lots of effort goes into developing an Android application. This book will help you to build you own Android applications using Java. Android Studio 3.5 Development Essentials – Java Edition first teaches you to install Android development and test environment on different operating systems. Next, you will create an Android app and a virtual device in Android Studio, and install an Android application on emulator. You will test apps on physical Android devices, then study Android Studio code editor and constraint layout, Android architecture, the anatomy of an Android app, and Android activity state changes. The book then covers advanced topics such as views and widgets implementation, multi-window support integration, and biometric authentication, and finally, you will learn to upload your app to Google Play console and handle the build process with Gradle. By the end of this book, you will have gained enough knowledge to develop powerful Android applications using Java.
Table of Contents (86 chapters)
86
Index

12.2 The Activity and Fragment Classes

With few exceptions, activities and fragments in an application are created as subclasses of the Android AppCompatActivity class and Fragment classes respectively.

Consider, for example, the simple AndroidSample project created in “Creating an Example Android App in Android Studio”. Load this project into the Android Studio environment and locate the MainActivity.java file (located in app -> java -> com.<your domain>.androidsample). Having located the file, double-click on it to load it into the editor where it should read as follows:

package com.ebookfrenzy.androidsample;

 

import android.os.Bundle;

 

import com.google.android.material.floatingactionbutton.FloatingActionButton;

import com.google.android.material.snackbar.Snackbar;

 

import androidx.appcompat.app.AppCompatActivity;

import androidx.appcompat.widget.Toolbar;

 

import android.view.View;

import android...