Changing DataGrid column width in Flex

One interesting find while working with Flex DataGrids is how they behave when you try change column widths at runtime using actionscript: They simple don't show any effect unless you turn horizontalScrollPolicy "off".

More on this at http://junleashed.wordpress.com/2008/07/10/flex-datagridcolumn-width-management/

Flex bug related to Compiled CSS

Recently while playing with .css files in Flex 3, I eventually used the option Compile CSS to SWF and it started giving errors on ClassReference everywhere inside the CSS. Then I found out its a Flex bug (http://bugs.adobe.com/jira/browse/FB-11925) and can be fixed simply by placing the .css files to the application root (though that may mean rearranging things here and there)

Additional information on the bug may be found at:

http://bugs.adobe.com/jira/browse/FB-23440

ObjectHandles in Flex 3 - Problem in switching to version 2 - OH v2

I've started with Adobe Flex 3 from a couple of weeks now and recently happened to use ObjectHandles library in one of the projects. The library is pretty good except that the usage methodology changes from version 1 to version 2.

e.g. one major difference is that I would use MXML tag notation to create object handles in version, but I couldn't do that in version 2. In v2, I had to create ObjectHandles object in actionscript at creationComplete event and then Register my component(s) with it. This made a real fuss the first time I switched my app from to use version 2, but later on (after checking out the supplied examples) I managed to deploy v2 without much of the problem.

catch block with no arguments?

I was at first surprised to see a catch block that does not accept any Exception types as argument. Something that looks like this:

try
{
//some lines of code...
}
catch
{
//fixation code...
}

What it actually does is catch all CLS (Common Language Specification) based and Non-CLS-based (exception raised by COM components) exceptions. Or for simplicity's sake we could think of as equivalent to the following (in .NET 2.0 or above):

try
{
//some lines of code...
}
catch(Exception ex)
{
//fixaion code...
}

Destructors in C#.NET

I find this topic really undiscussed among pure .NET developers (I don't know why they don't bother) Even I got to look at it when someone asked me how do we actually call destructors over an object in C#.NET.

A quick googling and here's a nice article on Destructors in C#.NET.

http://www.c-sharpcorner.com/UploadFile/chandrahundigam/UnderstandingDestructors11192005021208AM/UnderstandingDestructors.aspx?ArticleID=3cc8bfd4-d3ef-4bb2-bae9-41774fd943f7

Though needs a bit of work on English, its plainly written for someone like me.

Working around System.Runtime.InteropServices.COMException

Well, if you're trying to open up a solution in Visual Studio that has Web Services within and getting this annoying message about System.Runtime.InteropServices.COMException, ...

...

...

...

then all you may need to do is simply delete the (hidden) 'User Options' file in the folder where you've stored the .sln file, make sure IIS is already installed and there are Virtual Directories built up for you web service.

I tried to copy a web solution to a different machine than on which it was developed and I got this problem when I tried to open it in Visual Studio over the other machine. Just deleting that User Option file worked around for me.

You can also check out the following link for further information:

http://geekswithblogs.net/marocanu2001/archive/2008/05/20/annoying-visual-studio-2008-little-bug.aspx

Have fun!!!