Learn Android OS – Part 1

This new series of tutorials aims to familiarize you with the Android OS so you can write their own applications for Smartphone, and why not reach the top application on Android Market. Before starting you need to know quite well the Java programming language and object-oriented programming concepts.

Introduction – What is Android?

Android is an operating system for mobile devices (tablets and phones), based on a Linux kernel. It was initially developed by Google and later the Open Handset Alliance consortium. Android allows developers to develop applications written in Java programming language using libraries provided by SDK (Android does not provide all the class libraries and API complete the package Java SE or ME, so you can not run on Android any code written in Java ).

Android SDK includes a complete set of development tools. These include a debugger, libraries, a device emulator, documentation, etc. Development environment (IDE) is officially supported Eclipse (3.2 or later), using plug-in Android Development Tools (ADT), although you can use any text editor to edit XML files and Java and then use the tools of command line to compile/run/debug Android applications.

You can download the latest version of Eclipse from the official website for both Windows and Linux. Android SDK can be downloaded here (for Windows is recommended to use file. Exe)

ADT (Android Development Tools)

ADT is a plugin for Eclipse that helps developers to create Android applications easier. The features include: easy creation of IU’s, debugging applications in a GUI XML files for easy editing.

Install ADT

• to install the plug will have to follow these steps:
• in Eclipse, select Help -> Install New Software
• select the Add
• in the Add Repository dialog you can add the Name “ADT Plugin” and the Location link: https://dl-ssl.google.com/android/eclipse/
• after you have added a new repository in the window select Available Software Developer Tools and install components
• restart Eclipse for the plugin to be active

Set ADT

To configure the ADT plugin follow these steps:

• in Eclipse choose Window -> Preferences
• select Android from the left panel
• you will need to enter the path to the Android SDK. And finally select Apply and then OK

Android SDK and AVD Manager

The last thing we need to do before writing the first program is to install components of Android SDK. You can do this in Eclipse Window -> Android SDK and AVD Manager.

Here you can download the SDK’s for multiple platforms, which allow you to test your programs both on an emulator running Android 2.2 (Froyo) but also on an emulator running Android 2.3 (Gingerbread). Here you can download documents offline, or examples of applications.

Creating an AVD (Android Virtual Device)

In order to test programs in an emulator, you need to create an AVD, which is the specification that will have emulator.

• in Eclipse select Windows -> Android SDK and AVD Manager and here in the Virtual Devices tab, select New.
• here you can choose AVD’s platform or hardware emulator properties such as GPS support or support an SD Card.