Java Web Start application shows empty window on XMonad

Question

I use XMonad+gnome as window Manager. I have the problem that, when I run a Java Web Start applicacion, It olways show an empty window, like the screen:

Is there something I can do to fix it?

UPDATE:

I tried simple programs from JWS Examples and it works, right. So it should be a problem of the application.

The failed aaplication is Blast2Go.

Answer 1

Change the name of the window manager to a known one like LG3D:

startupHook = setWMName "LG3D"

Answer 2

I had the exact same problem with my own Java code and using the other suggested solutions (setWMName, MToolkit, etc.) did not solve the problem with Xmonad. I must note that in other window managers (e.g. fluxbox), the app works as expected. In my case, however, I figured out the problem. If you have access to the source of the Java app, I suggest you consider the following:

If you have any JFrame or JPanel or other containers, you should explicitly define their layouts. If you set the layout to null, then the dimensions of the container must be set explicitly. Otherwise, the container won't be rendered at all. For instance, I have a JPanel that contains all my widgets. I'd rather have full control over the layout, so I set the layout to null, and then explicitly set the dimensions for the JPanel:

jContentPane.setLayout(null);
jContentPane.setPreferredSize(new Dimension(appletWidth,appletHeight+100)); 

Hope this helps.