Scrolling of inside scrollable element results in skipping

[vualeks]

Hi,

I've just tried the example from the project, added just a few more elements to tableview that is inside and got this behaviour that I've recorded in video https://youtu.be/q4cU4kW-rcQ
It happens when panel is fully open, inside tableview is scrolled a bit up and then when you pulling it down it starts skipping when it reaches the end by pulling the panel to compensate. Maybe it's not well explained in words, but you can see it in video :)

Regards,

Aleksandar

[obianachebe]

I am seeing this issue as well

[MarioIannotta]

The bug is inside the function handleInternalScrollViewPanGestureRecognizer(_ gestureRecognizer: UIPanGestureRecognizer).

The problem is that when scrolling down from the beginning of the list yTranslation (handlePanGestureRecognizer#203) is 0,1,2,3 and so on; that means topConstraint.constant is progressively updated.

If the scroll starts, for example, from the second row (height = 30), yTranslation will be 0,1,2 but [1]shouldScrollingDownTriggerGestureRecognizer || shouldScrollingUpTriggerGestureRecognizer won't evaluate true untill the scroll view is scrolled to the end.

When [1] will be evaluated true yTranslation will be 30 and topConstraint.constant jumps from "some value" to "some value" + 30.

[idanboa]

any progress on this issue? @MarioIannotta

[MarioIannotta]

@vualeks @obianachebe @idanboa please checkout bugfix/17 and let me know if the fix works for you too and if you notice any regressions.
Thank you everyone!

[vualeks]

Hey @MarioIannotta ,

I've just tried it and it's much better than before, but still not quite as that google maps pull up. It doesn't constantly jump now when you pull it in that problematic way ( :D ), but pull view jumps only once to align to the scrollview position and then if you start pushing up (backwards) it jumps once again to realign itself. If you couldn't understand what I tried, I can make a video. Anyway, for me it's good enough, but you decide if you want to pursue any further.

Thanks for your work,

Aleksandar

[MarioIannotta]

@vualeks I got your point and you're right, this is an little improvement but the scrolling is not smooth and natural as it should be.
The "fix" has been merged in 3ef7316 (if you're using CocoaPods, please run a pod update) but I'll keep this issue open hoping that in future we come out with a better solution.