update(), aber not erase the the widget's area?

[blm]

hallo,

now i have a multithread program,
the work threader get data and send it to main Widget, than the data(point) will be painted in Widget.

to avoid flicker i used the updata() to schedule a paint event for the whole widget, but i still find flicker there and this method cost much time.

now i want only updata a small area where only paint the new point.

how I can do it?

[zavulon]

Use different overloaded functions QWidget::update(), which take a rectangle or coordinates of only a restricted region to be redrawn.