When using the Flex HttpService object to access an http resource from within your application, take care to test it under Internet Explorer too. Due to a bug in IE you could receive a Http Error or Stream Error in your Flex application when it’s running in https (secure) mode.
Normally when your backend responds to the HTTP request, it’ll use a Cache-control: no-cache, so the browser doesn’t cache the response in its browser cache. (as the response is normally dynamic and could change anytime).
As Flex is running in the Adobe Flash ActiveX player this however instructs IE to already delete the response, before the ActiveX plugin manages to get the results.
You’ll need to change your backend to set the following HTTP Response header:
This means: “do not store this response for any longer than necessary to display it” (more info at Atlassian)
Also check out Jim Robson’s blog and Mark Speck’s blog for more research regarding this issue.
Here are my Top picks for Devoxx 2008 University day 2:
The title of this talk is a little bit mysterious if you don’t know what Comet is about, but the content is looking very interesting.
The first part of the talk will be about HTML5 WebSockets and Server Side Events. WebSockets will enable full-duplex HTTP communication, and bring an end to the “click and wait” paradigm traditionally associated with the Web.
The second half of this university session will be about deploying and scaling “real-time” Web Applications. Eg. the server and network architecture, performance requirements and scalability of a bi-directional Web application will be discussed.
Check out Jonas Jacobi’s blog for more info!
Interested in the new Google Android phone? Then you certainly should not miss this univerity session by Romain Guy.
Romain Guy, who’s now working on the UI design of the Android phones as a Google engineer, always manages to impress the crowd with cool demos and knows what it takes to design a intuitive user-interface.
(which is more important than most programmers think!)
Chet Haase, who works on animation and UI components for the Flex SDK team at Adobe Systems, will likewise describe how to achieve beautiful Filthy Rich Client applications for Flex.
The IBM Rational Application Developer 7 (RAD 7) IDE, based on Eclipse 3.3 doesn’t work out-of-the-box with Flex Builder 3. This is due to the IBM Java SDK using a different Xerces version then the one Flex Builder needs.
You’ll likely receive the following error:
Here is an easy guide to get you up and running quickly:
- Install RAD7
- Install Flex Builder 3
- At the end of the install, the installer will complain about not being able to automatically setup an Extension Location. Be sure to execute the given instructions manually
- Quit RAD7 if running
- Edit the eclipse.ini file in c:\Program Files\IBM\SDP70 (directory where you installed RAD7)
- Add the following line on a new line at the end of the file:
Restart RAD7 and open the Flex Development perspective to start developing the next-gen Flex app :-)
Adobe Flex 3 and AIR 1.0 certainly have generated quite a buzz in the Java world in the last few months. Not in the least by the very nice Parleys.com site which is hosting all the Javapolis talks and videos.
Adobe AIR is a technology which lets you download and run webapps seamlessly on your desktop. (similar to Google Gears).
Another well known Google app, Google Analytics has now been ported to AIR by Nicolas Lierman. Analytics features all sorts of interesting statistics about your site visitors, allowing you to make informed choices on how to improve your site (eg. which pages are popular, which are not, which pages have high exit points, …)
The AIR version (with really nice Flex chart animations), can be download at AboutNico
One of the coolest Flex based RIA applications showcased during the Javapolis 2007 convention was the beta of the new Parleys.com website. Parleys hosts all videos and presentations from Javapolis and other BeJUG organized events and is great source of information for Java developers to stay current.
Now version 2 is available for testing at http://www.parleys.com/display/PARLEYS/Parleys.com+V2+BETA+Program
Be sure to check out the online version and the desktop version (showcasing Adobe AIR technology). As a JSF/Richfaces/AJAX developer I’m impressed by the speed & look ‘n feel of the site. Having to implement the below requirements is certainly not easy either with the traditional set of Java web tools.
- Full screen viewing of talks
- Add comments and tags in the presentation time line
- Bookmark talks and slides and forward them to a friend
- Change slide transitions