O’Reilly: Inside RIA

Last week, we talked about what delayed instantiation is in Flex and why it's used, as well as how to make sure all of the children of a Container are created before you try to address them. If you missed...

Delayed Instantiation is a technique in Flex whereby children of IContainer components aren't created until the user actually needs to see them. For instance, if you know that only the top half of your component will be showing, you can take control of the creation of children added to the component through MXML and only show the ones you know they will see at first. Then, when they scroll, you could show the rest. The most familiar example of a Flex component that uses delayed instantiation is ViewStack and its subclasses, Accordion and TabNavigator.

Flex comes with a full spectrum of components, but once in a while you get hit with a request to do something that is difficult to shoehorn into what already exists, but seems even more difficult to do as...

Recently, I decided to get my hands dirty with the latest build of Flex 4 SDK and Flash Builder 4. The new IDE has a lot of really exciting new features that will save developers a lot of time. The features that excite me the most are the new Spark components and skinning capabilities in the new SDK. Towards the beginning of the year I had read through the first few drafts of the new Spark component architecture, the style changes and how easy it is to skin components. Lots of things have changed since then, so I decided to refresh my memory and build a simple component to test my knowledge. Behold the SortableList component.

If you ever build your own custom components that extend UIComponent, you'll no doubt run into this scenario... Even if you add event listeners for keyboard events, or if you override the keyDownHandler function, you may find that your keyboard events aren't being handled by your component instances. Setting focusEnabled, mouseFocusEnabled, or tabEnabled don't seem to do the trick either... Don't pull your hair out! It's an easy fix. Read on to see how.

The other day I needed to create a few demo apps for one of my projects and was dreading dusting off my Flex skills to create some quick UIs. Don't get me wrong, I like Flex but sometimes I just need to do something quick and dirty in AS 3. That's when I remembered MinimalComps - the minimal AS 3 UI Component set by Keith Paters over at Bit-101.

FlexMDI is an excellent floating panel implementation.If you have tried other floating panel implementations then you know they leave much to be desired. DragPanel is awkward to work with, and does not provide much functionality. SuperPanel is very slow and...

As a Flex developer, one of the most valuable skills you can learn is custom component development. Although a lot of the training and information that's available for Flex focuses on how to use existing components, the truth is that memorizing every property of every Flex component isn't all that important. Eventually you're going to need custom graphics or functionality that no one ever anticipated, and this is where OpenFlux is going to make your day.

I've discussed graphics filters previously, and here's a trick to use them to extend the capabilities of basic Flex controls. In this example, graphics filters will be used to alter the appearance of a basic tree control. I've run into this scenario numerous times... How can you change the appearance of tree folder icons to imply meaning to the branches of the tree?

Ted Patrick has a nice overview of the Elixir data visualzation and charting components that iLog has been working on. They seem to be a good example of a commercial embracing Flex to create RIA components. There is some interesting chatter about paying for commercial components in the comments on Ted's blog worth checking out.