Outline What is Android? Why Android? Android Software Stack Android Development Environment First Android Application
What is Android ? Googles Android is the world’s most popular mobile platform. It is a modified version of Linux. “Android is a software stack for mobile devices that includes an operating system, middleware and key applications”.
History Android, Inc. was founded in October 2003 by Andy Rubin ,Rich Miner, Nick Sears and Chris White to develop, in Rubins words "smarter mobile devices that are more aware of its owners location and preferences".
Android Inc. acquired by Google in August, 2005. At Google, the developed a mobile device platform powered by the Linux kernel. On November 5, 2007, the Open Handset Alliance came with a goal to develop open standards for mobile devices.
That day, Android was unveiled as its first product, a mobile device platform built on the Linux kernel version 2.6. The first commercially available phone to run Android was the HTC Dream in 2008. Since 2008, Android has seen numerous updates which have incrementally improved the operating system, adding new features and fixing bugs in previous releases.
Version History Version Code name Release date API level 1.5 Cupcake April 30, 2009 3 1.6 Donut September 15, 2009 4 2.0–2.1 Éclair October 26, 2009 7 2.2 Froyo May 20, 2010 8 2.3 Gingerbread December 6, 2010 9 3.x Honeycomb May 10, 2011 12 4.0.x Ice Cream Sandwich December 16, 2011 15 4.1.x Jelly Bean July 9, 2012 16 4.2 Jelly Bean November 13, 2012 17
Features : Provides us SDK for developing Applications Runs on Dalvik virtual machine Video and audio codecs Bluetooth 3G, and WiFi, Camera Integrated browser based on the open source WebKit engine
Optimized graphics powered by a custom 2D graphics library; 3D graphics based SQLite for structured data storage Media support for common audio, video, and still image formats (MPEG4, H.264, MP3, AAC, AMR, JPG, PNG, GIF) GSM Telephony (hardware dependent)
Why Android? The ability for anyone to customize the Google Android platform The consumer will benefit from having a wide range of mobile applications to choose from since the monopoly will be broken by Google Android Men will be able to customize a mobile phones using Google Android platform like never before
Features like weather details, opening screen, live RSS feeds and even the icons on the opening screen will be able to be customized In addition the entertainment functionalities will be taken a much higher by Google Android being able to offer online real time multiplayer games
Android Software StackThe software stack is split into Four Layers: The application layer The application framework The libraries and runtime The kernel
Linux kernel The architecture is based on the Linux2.6 kernel. Android use Linux kernel as its hardware abstraction layer between the hardware and rest of the software. It also provides memory management, process management, a security model, and networking, a lot of core operating system infrastructures that are robust and have been proven over time.
Native Libraries The next level up is the native libraries. Everything that you see here in green is written in C and C++.
Android Runtime The Android Runtime was designed specifically for Android to meet the needs of running in an embedded environment where you have limited battery, limited memory, limited CPU.
Dalvik Virtual Machine The DVM runs something called dex files, D-E-X and these are byte codes that are the results of converting at build time.
Application Framework This is all written in a Java programming language and the application framework is the toolkit that all applications use.
Views that can be used to build an application, including lists, grids, text boxes, and buttons. Content Providers that enable applications to access data from other applications (such as Contacts), or to share their own data . Resource Manager, providing access to non-code resources such as localized strings, graphics, and layout files . Notification Manager that enables all applications to display custom alerts in the status bar. Activity Manager that manages the lifecycle of applications and provides a common navigation back stack.
Application Layer The final layer on top is Applications. It includes the home application, the contacts application, the browser, and your apps. And everything at this layer is, again, using the same app framework provided by the layers below.
Android Development Environment Java Development Toolkit Eclipse Integrated Development Environment (IDE) Software Development Kit (SDK) Android Development Tools (ADT)
Setup Eclipse IDE Download Eclipse IDE for Java Developer from the eclipse.org/downloads/ .
Setup Android Software Development Kit Download Android SDK from http://developer.android.com/sdk/index.html
extract the downloaded file and run the SDK Manager.
Choose the Android platform version which you wish to develop on and click Install packages. You will be prompted with a pop-up, check off Accept and click Install.
Setup Android Development Tools plugin Open Eclipse and select Help-->Install New Software
Click Add In the pop-up dialog, type ADT Plugin in the Name field and enter the following URL in the location field: https://dlssl.google.com/android/eclipse/
Select the Developer Tools option and click Next. Once the tools are downloaded, click Next.
Setup an AVD In Eclipse, navigate to Window --> AVD Manager. Click New… to fill in the details of the virtual device.
Application Components Activities represents a single screen with a user interface. A service is a component that runs in the background to perform long-running operations or to perform work for remote processes. A service does not provide a user interface. A content provider manages a shared set of application data. A broadcast receiver is a component that responds to system-wide broadcast announcements.
Create a Project with Eclipse1. Create Android Project
src/ Contains your stub Activity file. (e.g. all .java files). bin Output directory of the build. This is where you can find the final .apk file and other compiled resources. jni Contains native code sources . gen/ Contains the Java files generated by ADT, such as your R.java file and interfaces created from AIDL files.
assets/ This is empty. You can use it to store raw asset files. Files that you save here are compiled into an .apk file res/ Contains application resources, such as drawable files, layout files, and string values. res/drawable/ For bitmap and files and XML files that describe Drawable shapes or a Drawable . res/layout/ XML files that are compiled into screen layouts (or part of a screen).
5. AndroidMainfest.xml AndroidManifest.xml ,The control file that describes the nature of the application and each of its components. It describes:1. qualities about the activities, services, intent receivers, and content providers.2. what permissions are requested; what external libraries are needed.3. what device features are required,.4. what API Levels are supported or required.