Add keyboard support for insert table dropdown

[jodator]

While implementing insert table feature:

I've realized that it has no keyboard support defined. But I'd leave it as a followup to focus first on other missing features from MVP.

I also had some minor issues with getting this to work with FocusCycler and using <div tabindex="-1">. Also maybe I'm missing something but with current implementation of above dropdown I'd like to use methods like focus( 10 ) and focus( -10 ) to skip a whole row on arrowup and arrowdown.

For clarity this issue is only about properly handling the keyboard in table dropdown.

[oleq]

or just replace the grid by 2 inputs

That would make the UI nearly useless for anyone using mouse so it's definitely a no-go. The grid is one thing and the inputs are another, and I think what @Comandeer suggested is a very good idea in this case.

[mlewand]

The column/row count input has been extracted to a dedicated issue #11912 as it's a separate thing.

[mlewand]

This issue should be solved after we figure out how we want to handle grids in #11851.

Basically the idea here is to treat this grid as any other grid with following exception:

• As focused / hovered grid item changes the highlight should follow.
• As focused / hovered grid item changes the column/row number on the bottom should be updated accordingly.

We should also check RTL languages (because in this case the highlighting should go to bottom left corner).

[wimleers]

FYI: tracking this at https://www.drupal.org/project/drupal/issues/3283801 😊

[mlewand]

#3184 marked as a (partial) duplicate of this task.