I'm using QT and I have done a full screen application with some buttons and controls. Sometimes when an error pops up a dialog is showed and stay opened (stay on top).
I would like to have a button inside the application screen that could be pressed also when this dialog is opened, but all the other controls/buttons should be not usable.
I thought about something like a transparent custom widget with a special form over the application without covering the "special" button but I really don't know if it's so simply.