Greeter can be flicked away in the wrong direction

[Michael Zanetti]

Steps to reproduce:

* Start dragging the greeter slowly from the right (don't release it)
* when close to the left edge, do a quick flick (releasing it) to the right again
=> The greeter will move across the screen and hide to the right.

funnily it doesn't work like this the other way round.

Expected outcome:
If started dragging from the right it should only unlock to the left, if started dragging from the left it should only unlock to the right.

[Michał Sawicz (saviq)]

Not sure which part is the actual bug here... The fact that you *can* flick it, or that you cannot, especially since you can flick it both ways if started in the middle.

Adding ubuntu-ux for guidance.

[Daniel d'Andrada (dandrader)]

Just skimmed through the code. One source of the bug might be that you're not calling reset() on the EdgeDragEvaluators, as it should be done.

[Daniel d'Andrada (dandrader)]

I mean, calling reset() on every new touch down/mouse press, as it's a whole new drag. Thus you have to flush info from a previous drag.

[Daniel d'Andrada (dandrader)]

Btw, DraggingArea has been effectively obsoleted by DirectionalDragArea. Besides this code, it's only used by Revealer which, on its turn, was replaced by DragHandle.

So DraggingArea and Revealer should have been removed from the source tree by now. Well, not DraggingArea anymore as you're now using it. :)

Note that DraggingArea has its own velocity computation facilities, which for you is just a waste of CPU cycles as you're using EdgeDragEvaluators.

[John Lea (johnlea)]

Marking won't fix as dragging either direction to unlock is intended behaviour (it fixes a problem found in usability testing)