KNotifyConfigWidget: add disableAllSounds() method

Review Request #127926 - Created May 15, 2016 and submitted

David Faure
davidedmundson, ogoffart
This saves a lot of clicking compared to selecting each event
in the list and unchecking the "Play sound" checkbox, something
I have to do any time I set up a new computer (for me or around the office).

CCBUG: 157272

I'm calling this method from a button in the KCM:

My initial idea was a "disable all sounds for all event sources" button, but the underlying classes don't make this easy to support (I'd have to literally set every item as current in the combo, leading to a strange user-visible automation happening). Disabling all sounds for the current event source (app) is already quite a time saver.
Plus this way the change isn't saved yet, it can still be cancelled by pressing Cancel, like any other change -except- selecting another app.

Martin Klapetek
Olivier Goffart
David Faure
Review request changed

Status: Closed (submitted)

Change Summary:

Submitted with commit 9d5440c14cf9e8107f2cb270ad69cec98ab9303c by David Faure to branch master.