[Notifications KCM] Fix keyboard navigation in apps list
Summary:
Learned how to do this from @guoyunhe in D24798!
BUG: 409024
FIXED-IN: 5.17.4
Test Plan:
- Click on list item -> list gets focus, item is shown
- Use up and down arrow keys -> items are shown
- Click on search field and tab into list -> you can select things with the keyboard
- Search for something and click on or tab into apps list -> the correct item is shown
Reviewers: broulik, Plasma
Subscribers: plasma-devel, guoyunhe
Tags: Plasma
Differential Revision: https://phabricator.kde.org/D25309