Re: Sensors Extension.

[Adam Williamson <awilliam redhat com>]

On Tue, 2011-05-31 at 23:14 +0100, Another Sillyname wrote:

> There's plenty of space on the top bar to allow them, so what's the logic?

1) be clear about what's been removed. The sensors applet was never core
GNOME code; it's an add-on, an extra. What is removed in GNOME 3 is the
panel applet interface for add-ons to use. This is sometimes described
as 'removing applets', which in a way it is, but there's kind of a key
difference. The reason it was removed is that it was considered to be
bad code, and it was felt that in the GNOME 3 interface, there are
better ways than panel applets to add on functionality.

2) Reason the right way around. It's not the core GNOME development
team's job to write things like system monitor add-ons. How did
gnome-sensors-applet come about in the first place? As an add-on to
GNOME. Some people took a look at GNOME 2 and thought 'hmm, we should
add some way to do at-a-glance hardware monitoring'.

3) Follow the logic. So, in GNOME 3 - a complete rewrite of the GNOME
desktop - the core development team decided there was a better way of
allowing third parties to extend GNOME functionality than the panel
applet interface, and removed the panel applet interface. Since it's not
practical to wait for every third-party GNOME add-on ever to be
re-implemented in the new GNOME 3 ways, that means that the
functionality of some third-party GNOME add-ons will be unavailable in
GNOME 3...but _only_ until that re-implementation is done.

4) Reach the conclusion! It's not the core GNOME team's responsibility
to write add-ons (or...we could call them...extensions!) to GNOME. They
instead provide handy interfaces that others can use to write these
extensions. In GNOME 2, the panel applet interface was one of these. In
GNOME 3, it isn't; there is the much more powerful concept of Shell
extensions. You can write something as a GNOME Shell extension that
works exactly like a GNOME 2 panel applet; it just doesn't use
libpanel-applet any more. But it still walks, looks and quacks like a
panel applet. Some people have done this already. The GNOME design team
might think that's a bad way to design add-ons, generally speaking, but
hey, they don't get a vote on your third-party add-on. Or, you can take
advantage of the much greater power you have with Shell extensions to
come up with a neater way of implementing the functionality. The sky's
really the limit. 'GNOME 3 doesn't let you make panel applets' is the
pessimistic way of looking at it. 'GNOME 3 doesn't _only_ let you make
panel applets - it lets you extend it in far more ways!' is the
optimistic way of looking at it. All that needs to happen is for the
same (types of) people who wrote extensions for GNOME 2 as panel applets
to write similar (but probably better!) extensions for GNOME 3, as
extensions.

Sorry if that was long, but I wanted to make it as clear as possible. I
hope it helps.
-- 
Adam Williamson
Fedora QA Community Monkey
IRC: adamw | Fedora Talk: adamwill AT fedoraproject DOT org
http://www.happyassassin.net