Question

I am a linux (mostly ubuntu) user with a reasonable understanding of how the system works (although I am certainly not a linux guru!). In the past I have developed small cross-platform desktop applications in python/GTK and I delivered them to clients as self-contained filetrees, so that the only dependencies were Python itself and GTK.

Now I would like to develop a small applet for ubuntu, that I would like to release under GPL 2 or 3.

In particular these are the new steps I know I must learn in order to achieve my goal (it is very possible there are a few more that I am unaware of, though!):

• Integrating with gnome: I want my application to be available as an applet in the taskbar.
• Using D-bus: In particular I want my applet to use the new osd-notification framework for ubuntu, but communication with other applets is also a possible feature for a second iteration.
• Packaging: I would like to setup a public PPA as soon as the application will reach alpha stage, but I also would like to use dependencies from existing packages in the official repos, rather than include the libraries again in my own package.

Of course official documentation will be my first source of knowledge, but – basing my judgment on the very useful answers that I received on another topic here on SO – I decided to turn to the SO community to collect additional advice like for example:

1. Are there additional steps to those I outlined before, that I have to learn in order to be able to implement my project?
2. Based on your own experience, would you advise me to learn those steps in advance (as the knowledge of those will influence my way of coding the core functionality) or would you consider integration with gnome / d-bus and packaging as “higher encapsulating levels” that can be added on top of core functionality afterwards (note: D-bus will be used at first just for pushing data. Input data will be retrieved with a webservice)?
3. Would you advise me to separate my application in two packages (back-end and front-end) or to keep it together in a single package?,
4. Do you know of any useful resource that you would advise me to look at, for learning any of the things that I have to?
5. Are you aware of any common “beginner’s mistakes” that I should be aware of?

These questions are not meant to be exhaustive, though: if you feel that I am missing something from the general picture, you are more than welcomed to point me in the right direction!

PS: Should I have failed in explaining my final goal, take a look at project hamster: what I want to achieve is similar in terms of user interface (meaning: the applet should display the status and clicking on it should open the application itself, from which you could both configure the applet and perform various operations).

Answer 1

When I asked this question two years ago Ubuntu and Gnome were much closer to each other than they are today. At present (end of 2011) gnome adopted the gnome-shell, while Canonical decided to develop their very own UI (unity)…

Part of the tension that brought to the split specifically involved libappindicator, which makes the way I formulated this question (and probably part of the answers) obsolete.

Besides, there is now AskUbuntu on stack exchange, that would probably be a much better forum to ask about ubuntu-specific question.