When scrolling aggressively in the launcher, items go out of frame

[Martin Tapia]

When scrolling aggressively in the launcher, items go out of frame for a few moments (~500ms).

Everything works great when you scroll slowly, you get the nice rebound effect. But if you give your mouse wheel a really big spin, the scrollbar stays blocked in the direction you scrolled, and the items get hidden. Then, after you wait ~500ms, the items reappear (they even seem to be reloading: they go from transparent to opaque).

I made a video of it and uploaded it to youtube:
http://www.youtube.com/watch?v=8tTpuEtwefU
This is real-time, and as you can see the items can stay hidden for a pretty long time.

This is very frustrating and it's one of the first thing I noticed when I switched to using Unity!

(In the video, there seems to be a small glitch at the center of the launcher, I guess this is another bug due to me recording the screen)

[Bilal Akhtar (bilalakhtar)]

First of all, it is Unity 2D which you are using. Secondly, whether the rebound distance should be shortened needs design discussion. Marking bug appropriately.

[Martin Tapia (paps)]

I don't think it's a design issue. I mean, who would design it so that when you use the mouse wheel, items disappear? I think it's way more likely to be a bug in the rebound effect code.

But anyway, if you say so, OK. I'm just saying that nobody would design smooth scrolling this way. It feels really buggy.

[Gerry Boland (gerboland)]

Yes this isn't by design, I believe it is a bug in Qt, reported at https://bugreports.qt.nokia.com/browse/QTBUG-21328

The only workaround I have so far is to disable the bounce effect. I have played with the bounce distance and deceleration parameters to no avail, but I might give it another go.