For the past 2 hours I’ve been struggling with the regular expression engine of AS3. Normally, when I need to write an regexp, I test it in the Regular Expression Workbench, a .NET app which is quite handy. The problem however is that it uses the .NET syntax for regexes. Apparently, each programming language uses it’s own regular expression syntax. For example, in .NET you can create a named group using (?<groupname>), in AS3 you need to type (?P<groupname>). more…

Flex / Flash has a neat feature: doing math for you.

So when you want to know what 0.1 + 0.2 is, you don’t need your calculator, just use flex. The result: 0.30000000000000004.

WTF is that about?

I’m currently trying to find out a fix for this. ATM the only workaround is doing a

var x:Number = 0.1 + 0.2
Math.round(x*10) / 10

How hard is it to add to two numbers and give the correct result?

or of course

var x:Number = (0.1 + 0.2).toFixed(1)

Works for actionscript as well as JavaScript

By the way, it’s not only 0.3 which is causing problems. more…

The labelfunction of a listbased component is nice, but a bit limited.
For instance, you have to specify the (data)fieldname inside the function, which makes it impossible to use it for other columns. Wouldn’t it be nice if you could write one labelfunction for all your columns? I thought it would.

In order to accomplish this, I needed to have the columndata inside the labelFunction. At first, I was thinking of extending the labelFunction, but that wouldn’t help me much, because Flex was still sending only the original data and not the columndata. So I went deeper in the component, searching for the function responsible for calling the labelFunction.

more…

Sometime ago a wanted a tree with all different kinds of icons, depending on the type of the branch. Flex has some support for this, but only for embedded images. The problem was that I couldn’t use embedded images because the images are loaded dynamically from a database. So I had to find a way to fool flex, and the solution is quite simple. more…

I’m currently working on skinning an Flex Application, and I ran in some strange CSS behavior. When you skin a datechooser component and set some styles with CSS like this:

DateChooser{
	rollOverIndicatorSkin: Embed(source="/assets/skin/flex_skins2.swf", symbol="DateChooser_rollOverIndicatorSkin");
	selectionIndicatorSkin: Embed(source="/assets/skin/flex_skins2.swf", symbol="DateChooser_selectionIndicatorSkin");
	headerColors: #333333, #000000;
   	backgroundColor: #474747;
   	color: #a7a7a7;
   	headerStyleName: "mydateChooserHeaderStyle";
}
 
.mydateChooserHeaderStyle {
   color: #a7a7a7;
}

and insert a datefield, not all styles are applied to the build-in datechooser of the datefield (for instance, the background-color, it just stays white).

The solution to this problem is to use the date-chooser-style-name property of the datefield. You then can specify a classname for the datechooser. The problem with this solution is that you get two classes, specifying the same component.

But then I thought wait… It’s CSS right? So I can specify styles for multiple classes or containers, like this:

DateChooser, .date-chooser{
	/* code here */
}
 
DateField{
	date-chooser-style-name: "date-chooser";
}

I recently discoverd another bug in Flex 2.0.1 / ActionScript 3.0. You cannot trust the enabled property of some components. Especially listbased components like datagrids. When you set the enabled property of a datagrid to false, it still responses to doubleclicks and happily fires it’s events. Probably not what you want. The solution is fairly simple though:

<?xml version="1.0" encoding="utf-8"?>
<mx:Canvas xmlns:mx="http://www.adobe.com/2006/mxml"  >
	<mx:DataGrid
		id="contentitemGrid"
		doubleClickEnabled="true"
		mouseChildren="{contentitemGrid.enabled}" />
</mx:Canvas>

By disabling it’s mouseChildren property, the clickevents of the datagrids children (the items) aren’t fired anymore, so the doubleclick is ignored.