Expose DirectionalDragArea in the UITK

[Olivier Tilloy]

One strong principle in Ubuntu Touch’s UX is the use of edges.
In particular, the bottom edge is reserved for applications to implement innovative and useful interactions.

At the moment implementing such a gesture recognition in pure QML requires using an invisible mouse area at the bottom of the view to detect the start of a drag gesture. Unfortunately if there is content below that invisible drag area, it can’t be interacted with, because the mouse area will swallow mouse events.

In the unity8 code base, there is a custom component called DirectionalDragArea (implemented in C++) that solves this issue nicely. Unfortunately it’s private to unity8 and can’t be reused in applications.

This bug report is to request considering moving ownership of this component to the UITK, so that it can be exposed publicly and used by application developers.

[Olivier Tilloy (osomon)]

Note that the browser application now uses a local copy of unity8’s DirectionalDragArea to implement its bottom-edge interactions.

This means code duplication, on top of depending on private Qt headers, so it’s really not a comfortable situation.

[kevin gunn (kgunn72)]

fwiw, it is on the unity8 team backlog, unfortunately not with any priority atm

[kevin gunn (kgunn72)]

this is actively being worked, part of our apr 13 sprint

[Olivier Tilloy (osomon)]

Any updates on that one?

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Bartosz Kosiorek (gang65)]

Any updates on this one bug?

We need it to resolve issues with Ubuntu-calculator-app:
https://bugs.launchpad.net/ubuntu-calculator-app/+bug/1444564

[Daniel d'Andrada (dandrader)]

It's called SwipeArea in ubuntu-ui-toolkit