Maemo App Development - One Year Ago

I just realized that one year ago, I was giving a talk about Maemo Development at the Metalab here in Vienna. Back in January 2010, things were still very much different from today:

• Scratchbox was the SDK - Linux only, VMs for everything else
• No proper IDEs for Hildon development (there was Eclipse integration, but I never used it)
• Qt still was "the new stuff that's coming up" for Maemo development
• Mer was still something to look forward to
• MeeGo didn't exist - Maemo 6 was the future ;)
• MADDE was in Technology Preview state - not widely used
• Direct UI (now MeeGo Touch) was thought to be the future toolkit
• Qt 4.6 was just released in December - no QML in Qt yet

It turns out that we are in a much better position now, we've got a nice cross-platform IDE (Qt Creator), a proper SDK (Qt SDK) that works on Windows and OS X the same as on Linux and the "low-level" issues (optification, packaging, ...) are handled by Qt Creator mostly.

Today, the issues are different - I'm complaining about Qt Creator (from the Qt SDK 1.1 Preview) crashing a lot in QML design mode, I can deploy my apps to Symbian devices without much effort (didn't think I would ever do that) - even though there's no proper toolchain for Linux or OS X (Remote Compiler doesn't count). The Qt Quick Components are still not released, even though I'd love to create some great apps with them. And most people forget in the N9 rumor jungle that we have still got the best Linux-based mobile OS (with Linux userland) that exists in an actual product that you can buy right now (that's Maemo 5 on the N900 if you didn't get that hint..). Just like Duke Nukem Forever, a MeeGo handset will be announced and released eventually - give it some time.

Back to the "Qt Creator shouldn't crash when editing QML" developer story: We're not there yet, but comparing the current state with the state one year ago, that's some progress right there! Looking forward to those bits falling into place in the upcoming months.

Playing around with MeeGo Touch

While the MeeGo Touch Python Bindings are still not packaged and released, I though I'd give the C++ library a try and have a look through the class hierarchy. After getting the basic "Hello World" app running, I decided to create an application that can load the list of subscriptions from gPodder's SQLite database:

This view uses MContentItem, which already provides an icon and two lines of text - correctly styled and ready to go. Menu and toolbar items are MAction objects that can either appear everywhere or only at specific places (e.g. only in the toolbar). The great thing is that this all works on your Desktop in a normal window, so testing applications on your computer will be much easier with MeeGo Touch than it is with Hildon (which does not really run without its own hildon-desktop session in Xephyr).

The screenshot above is from the prototype written in C++, and shows how a gPodder MeeGo UI could look like. The MeeGo Touch UI of gPodder will be implemented in Python once the bindings are ready - the framework seems to be fun to work with so far. If you would like to play around with it yourself: MeeGo Touch is available from the MeeGo PPA of Ville M. Vainio if you are on Ubuntu and don't want to build it yourself.

SketchyAetch, gPodder/Qt and living in the present

After the very interesting Nokia Mobile Developers Forum in Hagenberg on Friday and Saturday (Petri Niemi did several interesting Qt introductory talks), I decided to play a bit with QGraphicsView again and this time try to come up with an app that actually does something: SketchyAetch!

Having not done much with C++ for several months, the GCC error messages (at least for C++) are still kind of cryptic. The fact that code gets pre-processed by moc does not help here, as the error messages might appear in a different location than where the real error/typo is. It should not be too difficult to get around these issues after some practice, and from that point on, getting things done (in C++) with the Qt libraries should be nice.

Already-drawn lines will fade away when you shake your device just like you would expect. The package is available in Extras-Devel.

Now something for the Qt fanboys out there: If you're running gPodder 2.3 on your device, you can try

   python -m gpodder.qtui

for a PoC "yes we could use Qt for the UI layer". This is not something that we will be working on in the near future (after all, the Hildon-based Maemo 5 UI is perfectly fine and "native" and it will get some more fine-tuning with the next release), but it shows that it won't be too difficult to do a DirectUI GUI for gPodder on top of the existing podcast client for M6/MG. We probably get around to implementing a DirectUI GUI for gPodder later this year when it's time to think about "Maemo 6" support.

Looking back how strange the gPodder Fremantle UI looked back in June 2009 (and how much changed in both the Framework and gPodder until the first Fremantle version was released), there's no rush in switching to Qt or DirectUI (at least for existing applications). I just hope that good Python bindings will be available for DirectUI/Qt when it's time to support the new UI, but I'm sure the PyMaemo team will do a great job just as they did with Hildon/Fremantle.

Maemo 5 is very polished these days, and I expect it to be even more mature when PR1.2 is out. It's also nice to see the Qt bits fall in place, DirectUI widget demos being made available, and MADDE becoming integrated with QtCreator, so the tooling support is ready when it's time to write M6/MeeGo apps. Maemo 6/MeeGo is for later this year, now it's time to enjoy Maemo 5, the N900 and all the great open source apps :)