I have used KDE and Qt applications for a decade but recently, after uptading my Gentoo system, a regression occured. When a scrollbar is scrolled by dragging its handle with the mouse, one must follow the scrollbar quite closely with the mouse cursor. If the cursor is moved a certain distance from the scrollbar, the handle suddenly jumps back to where the drag started. This is of course annoying and makes no sense. So it needs to be fixed. If the scrollbar is vertical, the x-coordinate of the mouse cursor should not matter during the drag. Searching the web only gives this information (http://doc.trolltech.com/4.6/qstyle.html):
Constant: QStyle::PM_MaximumDragDistance
Value: 8
Description: The maximum allowed distance between the mouse and a scrollbar when dragging. Exceeding the specified distance will cause the slider to jump back to the original position; a value of -1 disables this behavior.

So it seems like this is the default behavior (with a distance of 8 pixel). It seems to have been that way from Qt 4.0 to 4.7. But since I only noticed it recently (maybe KDE 4.5?) I suppose it is KDE that changed its default behavior. Where is the place where it can be set to -1?

This can only be set programatically, likely by the style you are using. I suggest filing a bug against Oxygen, as that is where this can be implemented in a KDE wide manner.

Which version of Qt and KDE Platform do you use, and which style? I can't reproduce it with Qt 4.7.1, KDE Platform 4.5.3 and the default Oxygen style.

Hans wrote:Which version of Qt and KDE Platform do you use, and which style? I can't reproduce it with Qt 4.7.1, KDE Platform 4.5.3 and the default Oxygen style.

I use Gentoo packages of Qt 4.6.3 and KDE 4.5.3. The style seems to be CDE. I am not sure what the style was before, but I have a vauge memory of a style called KDE (or was it Keramik?). Maybe the style I had was removed in 4.5 and CDE was used because it is first?

A strange thing is that it does not seem to matter what I select; CDE, Cleanlooks, Motif, Plastique or Windows. It looks and behaves the same way. I even tried to log out and restart kdm.

sigra wrote:A strange thing is that it does not seem to matter what I select; CDE, Cleanlooks, Motif, Plastique or Windows. It looks and behaves the same way. I even tried to log out and restart kdm.

Not sure I got it right - do the applications change style if you change between CDE, Cleanlooks etc.?

It seems like something is weird on your system, I can't imagine anyone using the CDE style on a regular basis. (Maybe you like the "old look"?)

Have you tried to reproduce this problem with the Oxygen style?