Indicator for number of notifications

[PVince81]

Following #126:

Add an indicator on top of the bell icon that displays how many notifications there are.

Do we want this to be the number of notificctions overall or unseen ?

I'm not sure we have the concept of "seen but not discarded" notification, so the former is the easiest.

@pmaier1 @felixheidecke

[pmaier1]

Do we want this to be the number of notificctions overall or unseen ?

Unread, I'd say.

[PVince81]

Let's try and think of the different levels of "unread" that could qualify:

• unread as "notification was never rendered nor visible to the user": when user opens the panel and the notification is rendered in the list, it is considered read
• unread as "notification was rendered but untouched": only if the user clicks it, it becomes read. (but does not take action)
• unread as "notification that wasn't acted upon yet": only if the user clicks an action or discards it, it disappears and gets uncounted

We also need to take into consideration that while the bell icon does not show the notifications until clicked, clients might use the desktop or mobile notification system in which case the user will directly see it rendered. On Plasma 5 I'd see a popup at the top right of the screen with the text of the notification. Would this qualify as read ?