Failed to load libGL.so

Here is the solution for error message 'Failed to load libGL.so' when launch Android Virtual Device (AVD) from Android Studio 0.2 on Ubuntu 13.04 32 bit:

Install 'Free Implementation of the OpenGL API-GLX development files' (libgl1-mesa-dev) package from Ubuntu Software Center

or type this command at terminal
sudo apt-get install libgl1-mesa-dev

Credit: http://learnedstuffs.wordpress.com/2012/07/17/fixing-ubuntu-error-failed-to-load-libgl-so/

C# Questions and Answers – Part 3

What is an anonymous class?
An anonymous class is a class that does not have a name. An anonymous class created by using the new keyword and and a pair of brace defining the fields and values.

How to prevent a calculation overflowed in C#?
Use checked keyword. For example: checked (operand1 + operand2); checked and unchecked keyworks are for integer arithmetic such as int and long

What is a partial class?
When we split a number of methods, fields, and constructors of a class into many files, we can use partial keyword.

Previous posts:
C# Questions and Answers
C# Questions and Answers – Part 2
C# Questions and Answers – Part 3

Install Windows 8.1 Preview on VirtualBox

When I installed Windows 8.1 Preview on VirtualBox 4.2.14 hosted on Mac OS/X machine, I got this error:
“Your PC need to restart, Please hold down the power button Error Code : 0x000000C4”.

Here is a solution I found at https://www.virtualbox.org/ticket/10792:
Open terminal windows and execute this command:
VBoxManage setextradata [vmname] VBoxInternal/CPUM/CMPXCHG16B 1
where [vmname] is your Windows 8.1 virtual machine name.

Here is my screenshot: Install Visual Studio 2013 Preview on Windows 8.1 Preview

Update on July 10: You need to the Oracle VirtualBox 4.2.16 or later to install VirtualBox Addition in order to make the full screen, shared folder and other features.

Notes on MVC Music Part 7 Tutorial

When using Visual Studio 2012 and MVC 3 to practice the MVC Music Store tutorial, you may get this error on part 7:
‘CompareAttribute’ is an ambiguous reference between ‘System.ComponentModel.DataAnnotations.CompareAttribute’ and ‘System.Web.Mvc.CompareAttribute’

Here is the solution:
Remove the reference using System.Web.Mvc;
from MvcMusicStore\Models\AccountModels.cs

Change Privacy Settings on Flickr

Recently Flickr increased the capacity of free plan to 1 terabyte. It’s great. Flickr is one of the best photos hosting web site. However, you need to review and change its default settings.

The default settings before change

Only myself can access to original file


Default settings for upload

Change it to myself

After the change of default upload.

C# Questions and Answers – Part 2

What is a constructor?
A constructor is a special method with the same name as the class. It is executed when an instance of the class is created and can contain code to initialize the instance.
What is the difference between public, static and void?
All these are access modifiers in C#. Public declared variables or methods are accessible anywhere in the application. Static declared variables or methods are globally accessible without creating an instance of the class. Void specifies that the method does not return a value.
What is an interface?
An interface contains only the signatures of methods, delegates or events. The implementation of the methods is done in the class that implements the interface. Read more http://msdn.microsoft.com/en-us/library/87d83y5b(v=VS.80).aspx
What is a delegate?
Delegate is a reference type that can be used to encapsulate a named or an anonymous method. Delegates are similar to function pointers in C++; however, delegates are type-safe and secure. Read more http://msdn.microsoft.com/en-US/library/900fyy8e(v=vs.80).aspx

Previous posts:
C# Questions and Answers
C# Questions and Answers – Part 2
C# Questions and Answers – Part 3

Scan a whole drive for virus in Windows 8

1. Go to desktop screen to using Windows Explorer or open command prompt windows.
2. Change to folder C:\Program Files\Windows Defender
3. Execute program c:msascui.exe