GateIn Portlet Refresh

Hello,

I'm very sorry to come back with this question, but I'm very impressed in Vaadin framework and I really would like to use it in my project. I'm facing a big refreshing problem in portlet deployed under gatein and I cannot use another portal than gatein (this is not my choice). The first time the portlet is installed or the first time the portal is started), everything is fine : the portlet is working. But if I change portlet window mode, or portal page configuration, its contents is not painted anymore, showing an undefined progress bar for ever !!!,
until a restartApplication or browser refresh is done.

Implementing PortletLinstener showed that the first time, these methods are called in sequence : init (from Application class), handleRenderRequest then handleResourceRequest. handleResourceRequest is called with an UIDL resource ID, which as far as I understand is a UI definition. But now if portlet window is changing state for any reason, only handleRenderRequest is called.

I've tried to force a repaint in handleRenderRequest using for instance :

mainWindow.setContent(mainLayout);
or
mainWindow.executeJavaScript("wnd.location.reload(true);");
or
mainWindow.requestRepaintAll()
or
mainWindow.requestRepaint()

I've also had a look around Refresher addOn without any success.

The only idea I have is to get the whole UIDL of the mainWindow in order to force client side to be refreshed.
Is it possible to do such a thing ?

Thanks a lot for your help, and thanks a lot for such a fantastic framework