Desktop icons doesn't support accessibility (specifically Orca)

[Sergio Costas]

[ Impact ]

Currently, the Desktop Icons NG (DING) extension included in Ubuntu doesn't support integration with screen readers like Orca. This is a disadvantage for visually impaired users.

Since DING is implemented as a classic GTK application, it should be easy to wire it up to make use of the accessibility functions already available thanks to the ATK library. A patch for that has been recently uploaded to upstream, after a fix for this was requested by an user.

The patch takes advantage of the already implemented keyboard navigation, and just makes these little changes:

* sets a readable accessible description for the Desktop Icons window (because the application uses the invisible title bar to communicate with the extension, thus it contains just "odd characters and numbers")

* sets an accessible description for each icon with the type and the visible name of the file, and marks each icon as focusable

* when an icon is marked as selected, it gives the focus to it, thus triggering the screen reader to read the accessible description

Also, the code for keyboard navigation is moved from the "key-press" event to the "key-release" event, because that's the event used by the accessibility subsystem, and not doing this results in an incorrect icon being read by it.

[ Test plan ]

* Enable the Orca screen reader by pressing Mod+Alt+S. A voice will say "Screen reader enabled" (or a similar, translated message).

* Click on the desktop to give the focus to it.

* Press the arrow keys to navigate with the keyboard through the icons. Only one icon should be highlighted, and it should change when the arrows are moved.

* After the test, the screen reader can be disabled by pressing the same keys combination.

Expected results:

The screen reader should say the type and name of the selected icon, every time the arrow keys are pressed to change the selected icon.

Current results:

The screen reader remains silent while navigating with the keyboard.

[ Where problems could occur ]

A change in the way GTK manages the focus could result in the keyboard navigation to work incorrectly.

[Ubuntu Foundations Team Bug Bot (crichton)]

The attachment "Patch to add accessibility support to 23.10" seems to be a patch. If it isn't, please remove the "patch" flag from the attachment, remove the "patch" tag, and if you are a member of the ~ubuntu-reviewers, unsubscribe the team.

[This is an automated message performed by a Launchpad user owned by ~brian-murray, for any issues please contact him.]

[Daniel van Vugt (vanvugt)]

The upstream commit for this might contain a minor mistake: 167dffc1da2363e63bdb00a5188544d03ba417a0 in HISTORY.md says the feature is introduced in 47.0.6 but the commit history seems to show it not appearing until 47.0.8

[Sergio Costas (rastersoft-gmail)]

Good point... 47.0.6 was the migration to Gnome 45, and 47.0.7 was the fix for the integration with other extensions...

This is odd... in my work's computer the HISTORY.md file is fine... I'll check in my home's computer...

[Sergio Costas (rastersoft-gmail)]

Fixed. This is what happens when working from two different computers O:-)