There is no such thing as doing something continuously in computers. Everything is digitized and quantified.
hmm...what i meant was that that it is being updated in 1 sec through timer...so that is what is continous..
When you change the value of the progress bar, call update(). When you click the button - call update().
to be precise i am calling it only in these two situation ,no More no Less,so why does it not update or calls paintEvent everytime...