JFXStudio: sketch, hack, share

Accessibility is a prime concern for software nowadays. Various countries and organizations have passed accessibility laws (section 508) or guidelines that regulate how accessibility for computer software should be achieved. However, there is no native accessibility support in JavaFX. We have developed a package to achieve at least basic accessibility – mainly for assisting visually impaired people with using our virtual event platform through a Screen Reader.

As Swing directly supports accessibility via javax.accessibility, we have added a Swing component to the enclosing JFrame via the non-public API of Scene. This Swing component then accesses the nodes in the JavaFX scenegraph which implement the Accessible interface in order to determine the position of the nodes and their content. The Screen Reader then queries the graph to gather information for output (e.g. text-to-speech, sound icons, or a Braille output). The source code of the solution can be found at:

http://code.google.com/p/fxaccessible/

To use the accessibility support, you just have to use the fxaccessible subclass instead of the JavaFX nodes. Also add some descriptionText for the non-text elements. Everything else should be automatically be done by Swings accessibility support. We have currently only tested the solution on with Apple VoiceOver. It would be great to get feedback for some other Screen Reader systems.

I’ve had an idea for a scenegraph debugging tool for years. Over the weekend I finally built one for JavaFX called SideHatch. Here’s what it looks like:

Click to run

The basic concept is a single jar which you can put into your app and invoke with a single line at the end of your run method:

	sidehatch.SideHatch.activate();

Once activated SideHatch will show you the view you can see above. If you click on Info it will list all set system properties. If you click on graph it will give you a list of all public nodes in all of your app’s stages (windows).

The really fun part is the Overlay button. It will put a translucent overlay on your windows that draws the visual bounds of your nodes. When you mouse over them you’ll see information about the node under the mouse cursor. If you click on the node SideHatch will take a core sample of your app. This core samples visually shows what’s under the cursor, digging down through each node and group and control. It represents it as the vertical diagram you see on the right side of the SideHatch window, with each area colored the same as the node.

SideHatch is now part of JFXtras.org and you can find the latest app and jars on my Hudson server here.

The tool has a lot of potential and would go far if we get some more interested developers.