QCheckBox trouble + How to refresh a paint window if an other is open over and select

[anda_skoa]

If you want to "freeze" a widget, simply set it to "disabled".

Not sure what you mean with not painting while not being selected.

When a widget has new data to display, it can simply request redrawing by calling its update() method.
Qt will then issue a new paint event and let the widget redraw itself.

If you need to share data between windows, simply pass a pointer or reference to that data, for example as an argument to the second window's constructor.

Cheers,
_