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Haiko Schol
12th August 2010, 14:18
I'm writing an application that, among other things, needs to display a scrolling text ticker.
QPropertyAnimation looked like it would do the trick. Unfortunately, as soon as the app starts
doing those other things (displaying image slide shows, videos, web pages, flash), the animation
stutters.
Since only the main thread can access the GUI in Qt, I believe I can't move the ticker to
another thread. Moving loading and scaling of the images for the slide show to another thread
helped, but not for videos (Phonon::VideoWidget) or other content (QWebView).
Am I missing something obvious, or is it really such a big deal to put smooth scrolling text on
the screen?

Lykurg
12th August 2010, 14:42
As soon as you block the main (gui) thread - why ever -, you can do what you want but you never will get a smooth scrolling ticker.

Also skipping the property animation could speed up: See the ticker class from the C++ GUI Programming book: http://www.informit.com/articles/article.aspx?p=1405544.