[Rhythmbox-devel] status icon plugin

[Jonathan Matthew <jonathan d14n org>]

Over the last few days, I've removed the tray icon/notification code
from the core of rhythmbox and reimplemented it as a plugin.  The main
reasons to do this were to remove a few hundred lines of weird tangled
code from RBShell and replace it with some nicer code off in a plugin
where I don't have to worry about it, and to replace EggTrayIcon with
GtkStatusIcon.

A few other things happened as a result.  I extended the existing
configuration for notification popups, allowing them to be displayed
whether the main window is visible or not; and I added a few different
modes for the status icon.  The modes are:

- no status icon visible (useful if you just want notifications)
- status icon visible while notifying
- status icon always visible
- status icon owns the main window (minimize/close-to-tray)

The second mode may be extended in the future to include things like
track transfers and podcast downloads, making it work like a
notification icon rather than a tiny proxy for the main window.

Except when in the last mode, the main window behaves like a normal
window now.  It doesn't hide in the tray when minimized, rhythmbox
doesn't keep running if you close it, and it doesn't remember whether it
was minimized or not between restarts.  The 'icon owns window' mode
provides all those things.

enjoy.