V6: Out of sync, WARNING: Warning: Ignoring variable change for non-existen

Vaadin 6 / 7 / 8
1

In vaadin 6, if you create new second window and then add a new subwindow to that window showing progress indicator, then if you remove that subwindow in a new thread via:

     synchronized (application){
         parent.removeWindow(w);
     }

it will show WARNING: Warning: Ignoring variable change for non-existent component, VAR_PID=PID81
and Out-of-sync error on the clientside. This never happens in the initially opened window, only if you open another main window.

2

also, I don’t think it’s even related to being run in a different thread. I have a special queue that runs after each processed request from user (NextConnectionQueue) and even then, if I enqueue such action there, it will still show out of sync error.

3

okay, after fiddling, it is trying to update window that was removed with this UIDL:

[[759, PID259, positionx, i] , [422, PID259, positiony, i] ] but that window was already removed

4

unfortunatelly, the only fix was to use my own patching library that uses javassist, to modify AbstractCommunicationManager.handleVariableBurst to always return true even if it fails