Hands on Android Developement

Android is one of the most popular operating system for mobile phones and tablets
such as windows is used for PCs. Android was built on Linux platform.It is maintained by google and comes in few different versions. If you want to become an android developer then there is a nice opportunity for you because there is a huge area of development in this operating system .

Before starting android development you should have knowledge of few basic things such as:
SDK: which is sort for software development kit is a programming package that enables a programmer to develop application for specific platform. Typically a SDK includes one or more API’s , programming tools and documentation.

API: Application programming Interface, is a set of routines , protocols,and tools for building software applications. A good API makes it easier to develop a program by providing all the building blocks.

Activity: An Activity represents a visual representation of the android application. Activity uses Views and Fragments to create the user interface to interact with the user.Fragments are component which run in context of an Activity.An app in made of more than one Activity.

View and View Group: Views are user interface widgets for example buttons or text fields. ViewGroup is also called Layout Managers.

Intents: Intents are asynchronous messages which allow the application to request functionality from other components of the android system eg. from services or Activities. Actually an Intent is an object that provides runtime binding between separate components( such as two Activities). The Intent represents an app’s “intent to do something”.
Android applications are primarily written in java programming. The java source files are converted to java class files by java compiler. The android SDK contains a tool called dx which convert java files into a .dex (Dalvik executable) file. All class files of an application are placed in one compressed .dex file.

Most of the developer practices android development on Eclipse .If you are new for Eclipse then you can download it from  http://www.eclipse.org/downloads and if you want to have android training then you can practice on http://www.developer.android.com   .Now enjoy android programming.

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Reset ubuntu 11.10 password

I was using Ubuntu 11.10 for a long time and once i lost my password. I have gone through various searches and here i am present with the solution of it through which you can reset your password manually.

you can set it with two methods the first is by booting it in recovery mode and the second is by using any live OS.

I will talk about the first method..

first step is to boot up Ubuntu, press and hold “shift” key while the machine is booting..you will get the GRUB menu.

select the second option which is recovery mode and press enter. After pressing enter the system will start booting and you will get a list of options. We will have to make file system writable so that we can change our password. To make it writable select the 3rd option which is remount and press enter. You will get a picture once press enter you will get recovery menu with a list of options.

Select the last option root and press enter. if the root account password is not set then you will get a shell prompt and you can enter the command to reset the password of any account #passwd enter the new password and confirm it by entering again. Now enter command ‘sync’ and press enter.After that a prompt will come with written password updated successfully.Now enter the command ‘reboot-f’ to reboot.

You have successfully reset your password now you can enjoy working with your Ubuntu OS once again.