What is Android Architecture?

                                  Android Architecture

Hi folks,
In our previous Android Tutorials, we have discussed quite a few concepts of Android development.
We have successfully set up android development environment in our last tutorial; I think that it is time to start with Android Architecture before starting basic android programing we must be aware of android architecture and layer's in android stack .

So lets take a take a quick walk through of the Android Architecture.

Android Architecture: Layers in the Android Stack

The Android stack, as the guys over at Google call it, has a number of layers, and each layer groups together several programs. In this tutorial I’ll walk you through the various layers in Android stack and the functions they are responsible for.

Following are the different layers in the Android stack:

1. Linux Kernel Layer
2. Libraries Layer
3. Application Framework Layer
4. Applications layer

Kernel Layer:

The basic layer is the Linux kernel. The whole Android OS is built on top of the Linux 2.6 Kernel with some further architectural changes made by Google. It is this Linux that interacts with the hardware and contains all the essential hardware drivers.

At the bottom of the Android stack is the Linux Kernel. It never really interacts with the users and developers, but is at the heart of the whole system. Its importance stems from the fact that it provides the following functions in the Android system:

• Hardware Abstraction
• Memory Management Programs
• Security Settings
• Power Management Software
• Other Hardware Drivers (Drivers are programs that control hardware devices.)
• Support for Shared Libraries
• Network Stack

As the Android is built on a most popular and proven foundation, it made the porting of Android to variety of hardware, a relatively painless task.

Libraries Layer

The next layer in the Android architecture includes Android’s native libraries. Libraries carry a set of instructions to guide the device in handling different types of data. For instance, the playback and recording of various audio and video formats is guided by the Media Framework Library.
This layer enables the device to handle different types of data. These libraries are written in c or c++ language and are specific for a particular hardware.

Some of the important native libraries include the following:

Surface Manager: It is used for compositing window manager with off-screen buffering. Off-screen buffering means you cant directly draw into the screen, but your drawings go to the off-screen buffer. There it is combined with other drawings and form the final screen the user will see. This off screen buffer is the reason behind the transparency of windows.

Media framework: Media framework provides different media codecs allowing the recording and playback of different media formats.

SQLite: SQLite is the database engine used in android for data storage purposes.

WebKit: It is the browser engine used to display HTML content.

OpenGL & SGL: Used to render 2D or 3D graphics content to the screen.

Free Type: Font Rendering.

Open SSL

Android Runtime

Android Runtime consists of Dalvik Virtual machine and Core Java libraries.

Dalvik Virtual Machine

It is a type of JVM used in android devices to run apps and is optimized for low processing power and low memory environments. Unlike the JVM, the Dalvik Virtual Machine doesn’t run .class files, instead it runs .dex files. .dex files are built from .class file at the time of compilation and provides hifger efficiency in low resource environments. The Dalvik VM allows multiple instance of Virtual machine to be created simultaneously providing security, isolation, memory management and threading support. It is developed by Dan Bornstein of Google.

Core Java Libraries
These are different from Java SE and Java ME libraries. However these libraries provides most of the functionalities defined in the Java SE libraries.

Application Framework Layer

Android applications directly interact with these blocks of the Android architecture. These programs manage the basic functions of phone like resource management, voice call management etc.

Important blocks of Application framework are:

Activity Manager: Manages the activity life cycle of applications.

Content Providers: Manage the data sharing between applications.

Telephony Manager: Manages all voice calls. We use telephony manager if we want to access voice calls in our application.

Location Manager: Location management, using GPS or cell tower.

Resource Manager: Manage the various types of resources we use in our Application.

Application Layer

The applications is the topmost layer of the Android stack. An average user of the Android device would mostly interact with this layer (for basic functions, such as making phone calls, accessing the Web browser etc.) and this is where our applications are gonna fit. Several standard applications comes pre-installed with every device, such as:

• SMS client app
• Dialer
• Web browser
• Contact manager
• Games etc.

As a developer we are able to write an app which replace any existing system app. That is, you are not limited in accessing any particular feature. You are practically limitless and can whatever you want to do with the android (as long as the users of your app permits it). Thus Android is opening endless opportunities to the developer.

I hope you are clear with the basic Android architecture now! So, in next tutorial we will see what are the android app components. So, Stay tuned for more android development tutorials.

This tutorial has been written with an aim to teach you and explore a little bit about what is android architecture. #Some of Stats/Info mentioned in this post are taken from Wikipedia. They are subjected to changes as android technology is growing very fast.

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How to Set up an Android Development Environment

How to Set up an Android Development Environment

Hello Guys,
Welcome back to my second tutorial on android application development series as promised in last tutorial, we will take a look at Ho to set up an android development environment.
Android is based on the Java development language and any beginner-level Java developer can jump right in and start developing applications.
The purpose of this guide is to outline in detail the steps necessary to set up the initial development environment for creating Android applications. The guide will address the installation of the Android Software Development Kit (SDK) and the initial set-up necessary for allowing Android OS emulation.

Most preferred operating systems which are used for development:

• Microsoft Windows XP or later version.
• Mac OS X 10.5.8 or later version with Intel chip.
• Linux including GNU C Library 2.7 or later.

Second thing is that all the required tools to develop Android applications are available at free of cost and can be downloaded from the Web. Following is the list of software's you will need before you start your Android application programming.

• Java JDK5 or JDK6
• Android SDK
• Eclipse IDE for Java Developers (optional)
• Android Development Tools (ADT) Eclipse Plugin (optional)

So let us have a look how to proceed to set required environment.

Steps:

1. Download an IDE:

For the purpose of this example, will be using Eclipse. You can download the latest version of the software here: http://www.eclipse.org/downloads/packages/release/indigo/r.
You must choose the version that corresponds to your OS of choice. Install Eclipse. Make sure to take note of the installation directory and workspace for later reference.

2. Download and install the Java Runtime Environment (JRE).

You can find the download file here: http://www.oracle.com/technetwork/java/javase/downloads/jre-6u25-download-346243.html.

3. Install the Android SDK:

• The SDK starter package includes the Android SDK and AVD Manager. This is a tool that we will now use to download some required SDK components into our development environment.
• The starter package we downloaded only contains the newest version of the SDK tools. In order to develop Android applications, we will need to download at least one Android platform so we can emulate a phone/tablet via our computer hardware.
• In the root of the SDK directory, find and execute the SDK Manager.exe file. Note: Right-click and run as administrator to avoid any permission declination.

4. Download and Install the Android Development Tools (ADT) plugin for Eclipse

• Google provides a custom plugin for Eclipse, called ADT, that aids developers in creating Android applications faster and more efficiently.
• Open Eclipse and select Help and 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://dl-ssl.google.com/android/eclipse/

Now select all the listed plug-ins using Select All button and click Next button which will guide you ahead to install Android Development Tools and other required plugins.

5 - Create Android Virtual Device

Well last to test your Android applications you will need a virtual Android device. So before we start writing our code, let us create an Android virtual device. Launch Android AVD Manager using Eclipse menu options: Window > AVD Manager> which will launch Android AVD Manager. Use New button to create a new Android Virtual Device and enter the following information, before clicking Create AVD button.

If your AVD is created successfully it means your environment is ready for Android application development. Better you re-start your machine and once you are done with this last step, you are ready to proceed for your first Android example but before that we will see few more important concepts related to Android Application Development, in our next tutorial named: What is Android Architecture?

This tutorial has been written with an aim to teach you Set up an Android Development Environment. #Some of Stats/Info mentioned in this post are taken from Wikipedia. They are subjected to changes as android technology is growing very fast.

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Android Application Programming Overview

Hello Guys,
Welcome to my first tutorial on android application programming. First lets see a quick overview of android itself, then we'll move on to necessary environmental setup. So without wasting our time lets dig in it, here we go:

What is Android?

Android is an operating system based on the Linux kernel, and designed primarily for touchscreen mobile devices such as smartphones and tablet computers. Initially developed by Android, Inc., which Google backed financially and later bought in 2005, Android was unveiled in 2007 along with the founding of the Open Handset Alliance: a consortium of hardware, software, and telecommunication companies devoted to advancing open standards for mobile devices. The first publicly available smartphone running Android, the HTC Dream, was released on October 22, 2008.

It is world's most popular mobile OS:
Android powers more than a billion phones and tablets around the world. It’s customizable, yet easy to use, and since it's made by Google, it works seamlessly with all your favorite Google apps.

Open Source:

Android offers a unified approach to application development for mobile devices which means developers need only develop for Android, and their applications should be able to run on different devices powered by Android. The source code for Android is available under free and open source software licenses. Google publishes most of the code under the Apache License version 2.0 and the rest, Linux kernel changes, under the GNU General Public License version 2.

Features of Android:

Following is a list of features in the Android operating system:

Android Applications:

Android has a growing selection of third party applications, which can be acquired by users either through an app store such as Google Play or theAmazon Appstore, or by downloading and installing

the application's APK file from a third-party site.
The Play Store application allows users to browse, download and update apps published by Google and third-party developers, and is pre-installed on devices that comply with Google's compatibility requirements. The app filters the list of available applications to those that are compatible with the user's device, and developers may restrict their applications to particular carriers or countries for business reasons. Purchases of unwanted applications can be refunded within 15 minutes of the time of download, and some carriers offer direct carrier billing for Google Play application purchases, where the cost of the application is added to the user's monthly bill. As of July 2013, there are more than one million applications available for Android in the Play Store.

So guys this is my very first post on Android Application Programming and Overview of Android OS.

This tutorial has been written with an aim to teach you how to develop and package Android application. I'll start from environment setup for Android application programming and we will also see How to configure Eclips IDE for the same.
#All Stats mentioned in this post are taken from Wikipedia. They are subjected to changes as android technology is growing very fast.

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10 Tricks to Boost Your Productivity While Using Eclipse IDE

Hi guys,
Lets see 10 tricks that I find out as cited on eclipsesource.com to Boost Your Productivity While Using Eclipse IDE, which  are worth sharing with you folks.

What I felt from my personal experience is that those who have just begun using Eclipse or have had “some experience” have used Eclipse only as a text editor or handled it in a really heavy way. The main issue being that they have not yet learned about Eclipse’s capabilities and how to utilize its strong features.

So here are the top ten things, which will make your programming life a lot simpler and increase your productivity.
1. Letting Eclipse do the typing - A great IDE must assist the developer in writing his code quite instantaneously. Eclipse does this using Refactoring's, Quick Fixes, Code Assist/Code completion and more.  

2. Type Filters (for PDE / RCP developers) - Type Filters take out suggestions for certain types (e.g. classes, interfaces) from the “Open Type” dialog, content assist and quick fix proposals. As an RCP/SWT developer you would not want suggestions for Swing components like Button, Label, etc. You can find this setting in: Preferences > Java > Appearance > Type Filters

3. Text File Encoding - The default setting for saving files in the Eclipse workspace is through the useof file encoding of the underlying operating system. But you generally want to make a platform independent application. For accommodating this, set the file encoding to UTF-8. Using UTF-8 will prevent problems with special characters if deployed to a system running a different OS, running your build on a UNIX machine or in case someone else works on the code by using a different OS.

4. Save automatically before build - One thing I noticed is that people (including me) are constantly hitting Ctrl+S to save or even worse — grabbing the mouse to hit the Save action in the toolbar. This behavior seems to originate from experiences where an application was started from the workspace without saving and of course, changes were then lost. You can save some keystrokes and mouse clicks by enabling Save automatically before build. This is in: Preferences > General > Workspace

5. Use “Step Filtering” for Debugging – Using “Step Filters” you can filter out types you do not want to see, or step through while debugging. This assists you in staying focused on the actual code and does not expose you to the inner workings where you may not have the source.
6. Always launch the previously launched application - This option is for ensuring that your last launched configuration is utilized. Mentioned in the default setting, Eclipse strives to determine the most appropriate configuration for the currently selected resource that can be quite irksome. Set this under: Preferences > Run/Debug > Launching

7. Storing Your Launch Configuration in a Project – A great deal of time is invested in creating a launch configuration. It can be stored as a file in one of your projects. This allows you to share it with colleagues and save them from reinventing the wheel. You can find it in preference in: Menu: Run > Run Configurations... > Launch Configuration Tab: Common

8. Making a Launch Configuration always appear in the Menu – In case you have various Launch Configurations, you can select your favorite ones and stick them permanently to your Launch/Debug menu. You can go to - Menu: Run > Run Configurations... > Launch Configuration Tab: Common

9. Organising imports on save - The imports are instantly added to the class file. However, changing or removing code might make some imports useless. To fix that, you can Organize Imports by pressing shift+crtl+o or shift+cmd+o on a Mac and your imports will be cleaned up. You can also enable Organize imports on save and Eclipse will take care of it instantly. This can be found in: Preferences > Java > Editor > Save Actions
10. Formatting edited lines on save - The code formatter in Eclipse is quite a handy feature ensuring the code appears consistent in your projects irrespective of who has written it. It can also be easily read and understood by anybody. However, formatting the entire file can mess up the difference between two versions of the file. You can find this in -Preferences > Java > Editor > Save Actions.

Hope these tweaks/tricks will help you improve your productivity with eclipse as it helped me even after roughly 4 years of break. 
HBK Says, " Happy Codding Have Fun " folks.

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How to Install BackTrack on Android Mobile and Tablet

Hi Guys,

Lets see How we can Install BackTrack on Android Mobile and Tablet:

BackTrack Linux is a fine example of a specialized Linux distribution. Its only purpose is to test your network, devices, and systems for security vulnerabilities. BackTrack is packed with every security and hacker tool used by security professionals and professional hackers. I
f you're looking for all of the tools in one place, this is it. 

BackTrack is one of my favorite OS. First reason is it is made by world class hackers and second one is all hacking tools are available and last but not list one, it is flavor of Linux butI can use it only on PC. Android is booming now these days... Now you can Install Back Track Linux OS on Android smartphones and tablets. Now it is possible to install and run Backtrack on your Android devices.


Requirements:
(1) Root
(2) 1GHZ processor (recommended)
(3) 512MB Ram (recommended)
(4) Android 1.6 or higher
(5) Back Track 5 (http://goo.gl/CVVHgu)
Kernel will loop device support (this is included in most custom ROM’s)
(6) SD card with at least 3.5GB of free space
(7) Data connection on your device


Following Android Apps:

1.BUSY BOX (https://play.google.com/store/apps/details?id=stericson.busybox&feature=search_result#?t=W251bGwsMSwxLDEsInN0ZXJpY3Nvbi5idXN5Ym94Il0.) : It acts like a installer and uninstaller.it needs root permission to run.it has CPU cores and can run Linux kernels on android. click here

2. Superuser (https://play.google.com/store/apps/details?id=com.noshufou.android.su&feature=search_result#?t=W251bGwsMSwxLDEsImNvbS5ub3NodWZvdS5hbmRyb2lkLnN1Il0.) : This app just grants a superuser power to your phone just like "su " does for Linux. click here

3. Terminal Emulator (https://play.google.com/store/apps/details?id=jackpal.androidterm&feature=search_result#?t=W251bGwsMSwxLDEsImphY2twYWwuYW5kcm9pZHRlcm0iXQ..) : Terminal Emulator is app that runs a terminal console in android. click here

4. Android VNC (https://play.google.com/store/apps/details?id=android.androidVNC&feature=search_result#?t=W251bGwsMSwxLDEsImFuZHJvaWQuYW5kcm9pZFZOQyJd) : Android VNC is a tool for viewing VNC in Android.

How to Install Backtrack on Android Tablet or Phone?


Download the complete set of files you need from here: 

http://goo.gl/CVVHgu

To your phones internal SDcard in a directory called “BT5″ (cAsE sEnSiTiVe)
Launch "Terminal Emulator" from your phone and type (everything after the $: or #: is user input):
$: su
#: cd sdcard
#: cd BT5
#: sh bootbt
#: export USER=root
#: vncpasswd
(make up a password"ex: toortoor")
#: tightvncserver -geometry 1280x720

While Backtrack is loaded (when you see a red “root@localhost“) start the VNC server by typing:root@localhost:~#: startvnc (stopvnc kills it)
Open 'AndroidVNC' and fill the form like this:
Nickname : BT5
Password : toortoor
Address : 127.0.0.1
Port : 5901

Connect it and you will see Backtrack 5 interface. Voila you just did it... Enjoy..!

Remember: Some of the Backtrack tools can’t work properly and do it for your own risk. I hope you can Install Backtrack on Android tablet without any problems, tell me if you get problems.

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