Over the new year break I discovered Adobe Flex and have fallen for it, big time. Although I knew of it's existence before, I'd kind of written it off as being "just Flash". Now I can't believe I went this long without taking the time to find out more. Although it is "just Flash" it's an amazing tool that I can't encourage you enough to take a look at.

Don't worry, developing in Flex is nothing like developing in Flash. If you've tried creating Flash movies you'll know what hard work that is. With Flex it's much easier and there are many parallels with usual HTML-based web development. The learning curve isn't very steep at all. More of a gentle slope.

What is Flex?

It's a way of creating Rich Internet Applications (RIAs), which are based on Flash and so packaged inside a single SWF file. You embed this file on your webpage - like a normal Flash "movie" - and there you have it - a "rich internet application".

Here's an example - a "document explorer" I've been playing with which lets you find certain documents from within the Dext database. Click the image to take a look.

Like the accounts interface I mentioned the other day it's not so much a useful application as it is a way of me getting to learn the ins and outs of Flex. What you see though didn't take long at all.

Is it the Future of the Web?

No. As I see it Flex is only really useful when creating applications. If you want to create a typical website, such as a forum, blog or other heavily text-based site (that you want Google to index) then HTML is still the only answer. If, however, what you're building is more like a typical desktop-based application then maybe Flex could make building it on the web a whole lot simpler. As ever it's horses for courses.

For every project I've worked on recently where I can see Flex might have worked I can think of at least one other where it wouldn't have.

When It Comes In Handy

My interest in Flex came about as I am currently tendering for a couple of projects where the systems are required merely to "report" on data in a database. In one case the client wants nothing more than a web-based interface to view what data is held. The interface then need to allow further sorting/filtering of the data. Custom view-building if you will. Flex is a perfect fit.

Trying to design an HTML-based layout and interface (from scratch) can take way too long and be a nightmare to make it cross-browser. That's before you get as far as choosing the JavaScript framework to use or go about finding the most suitable plugins to add - such as, say, a date picker. When you do find those plugins you then need to extract all the files and carefully add them to your project. As you must know by now web development can be a chore at times.

With Flex developing it becomes a pleasure again. You do it all from with Adobe's Flex Builder app. You can either code by hand or use drag and drop to place elements on the work area in a WYSIWYG manner. Most of what you need comes as standard so you don't need to choose additional plugins or worry about where to put the myriad files that accompany them.

Can Anybody Use It?

More or less, yes. To use a Flex RIA you'll need Flash Player version 9 or later. Looking at the stats for codestore.net it looks like 90-something % of you do. Whether this is an issue or not depends on who your user-base are.

In most cases, for web-based applications that suit Flex, I'd imagine it's a corporate environment and you know they should have it or can insist they get it if not.

What About Accessibility?

I could be wrong but, like Flash, I imagine Flex is inaccessible. If this is an issue then Flex probably isn't for you.

Is it better than Ext?

Flex and Ext are very similar. They do a lot of the same things out of the box. Personally though I've not found Ext that much fun to develop with. You need a first class degree in JavaScript to get the most out of it. Most of us (myself included) only have a second class degree. I find Ext messy and almost cumbersome. Flex feels much cleaner. I know which I'd rather use.

Ext, however, is probably a better fit for Domino. Ext allows you to embed an iFrame with a standard Domino page/form in it. You can create/edit/save documents without needing to do much to the form at all. With Flex it's a different story. You have to create the whole form in Flex code and make sure the names match with the backend form. Any new fields on the Notes form would mean recompiling and uploading a new SWF after having added the new field in Flex.

Further Reading

There are plenty of example Flex applications out there to get you excited. Start with the Flex Showcase. If that doesn't work for you take a look at the Flex Component Explorer or the samples tab of Flex Developer Center -- such as this dashboard app.

Here's a video of somebody building a simple Flex app so you can see what's involved. My next post will show the basics of plugging a Flex app in to a Domino database.