Introduction - an overview
Android is an open source operating system and has several major releases each having several minor revisions. Android devices come in all shapes, sizes, and colors (e.g. phones, tablets, tvs and watches). To keep up with the latest technology, new versions of the Android platform are released frequently (APIs and SDK). We assumes that you know Java, if you do not, you will need to learn Java before you go further.
Setting-up Android Development Environment
The Android Studio platform includes Android Studio IDE, SDK Tools, Google API Libraries, and system images needed for Android application development. Android Studio is the official IDE for Android application development, based on IntelliJ IDEA. On top of the capabilities you expect from IntelliJ, learn what Android Studio offers among many others.
Understanding SDK Manager
Android Software Development Kit (SDK) is required to build any application for Android. It is the skeleton for any Android development. It contains dozens of support tools, platform details, APIs, libraries, system images, emulator and more.
Creating a new project in Android Studio
In previous page you've covered the steps necessary to configure an environment suitable for the development of Android applications using the Android Studio. Now its time to validate that all of the required development packages are installed and functioning correctly by creating an Android application. So in this tutorial we'll cover the creation of a basic Android application project.
Look at a few key areas in Android Studio
Android Studio is a sophisticated tool therefore it has dozens of properties to make app development easier. It's quite overwhelming for a first look at a project. Let's take a look at a few key areas in Android Studio which will clear this up.
Folder and File Structure
The Project tool window has several views, including the Android view, the Project view, and the Packages view. Each view shows the same stuff, but each view organizes this stuff a bit differently. This tutorial describe the types of files you can include in your project, including where XML files are located, where image are stored, and where the Gradle build files are stored.
Build and Run Your First Android App
To run an Android app, you need a device - either a real device or a virtual device. The Android Virtual Device Manager allows you to create Android Virtual Devices (AVDs), which you can then run to emulate a device on your computer. Android Virtual Device Manager make a testing environment using Linux kernel and Android SDK in order to emulate the environment found on the physical Android device.
Understanding Activities
Android apps are made up of Activities. The Android Activity class android.app.Activity is core to any Android application. Typically, one Activity is displayed at a time and this Activity occupies the entire screen. Each Activity is made up of views, which are the most basic building block of a user interface.
Working with Logcat
Logcat is an important part of everyday development. If you see one of those "Force Close" or "Has Stopped" dialogs, the first thing you will want to do is examine the Java stack trace that is associated with this crash. These are logged to a facility known as Logcat, its purpose is to display all logs coming from your device. It displays logs from an emulator or a real device connected.
Views, View Groups and Layout Editor in Android
The basic unit of an Android application is an activity, which displays the UI of our application. The activity may contain widgets such as labels, buttons, text boxes, and so on. Typically, we define our user interface using an XML file. In this tutorial we'll use activity_main.xml file for creating the UI, which is located in the res/layout folder of our project.
Dig a little deeper into the palette
The Android Studio palette contains various different views that we can drag onto the "design editor" representing the display of an Android device. These views are divided into categories and are all covered in this section.
The Manifest file
The Android manifest file is like an Android application's signature for the Android operating system. The manifests folder includes the AndroidManifest.xml file, this file is important to the application, as it contains all the definitions, such as package name, activities, services, minimum level of the Android API, linked libraries, and permissions that allow the Android OS to launch and run the application.