Qt for Maemo 5, next iteration

With all those Qt releases happening, I feel like we need a new acronym. How about YAQR (Yet Another Qt Release)? So - we're happy to announce YAQR, the second Technical Preview of Qt for Maemo 5 (official announcement). This release focuses mainly on deeper integration with Maemo 5. Lots of widgets received updates to make them more finger-friendly. Kinetic scrolling has been updated to feel just like the native Maemo 5 one. Native dialogs are now used, and QStyle supports the native Maemo 5 themed icons. Several new Maemo 5 specific classes were added:

• QMaemo5ValueButton: Implements a "Picker Button", basically a button with an extra value
• QMaemo5KineticScroller: Implements the Maemo 5 kinetic scrolling algorithm
• QMaemo5AbstractPickSelector: An abstract interface to implement Maemo 5 "pickers", plus a picker implementation for time picking
• QMaemo5InformationBox: Support for Maemo 5 Banners and Notes
• QMaemo5EditBar: Support for Maemo 5 Edit toolbar

In addition, we added some new window flags to support special Maemo 5 features:

• Busy indicator for windows and dialogs
• Portrait and landscape orientation (listening for orientation changes still has to be done via D-Bus - see the Maemo 5 widget example)
• Stacked windows to support Maemo 5 "Window Views"
• Support to disable window compositing in the window manager to improve drawing performance

As a special treat, we managed to improve the OpenGL ES 2 support (*). This was quite a tricky task, since the Maemo 5 input methods rely on native X11 controls. The OpenGL ES 2 graphics system requires all Qt widgets to be "alien widgets" (non-native widgets on an OpenGL surface), though. We fixed that with some proxy magic, so now we can have all Qt widgets on OpenGL ES 2 surfaces but still integrate properly with native input methods.

And now for the mandatory video, showing all those nice improvements:

How do I get it?

We have Debian packages, hosted by maemo.org, so it is no longer necessary to compile Qt. Short story: Add Maemo's "extras-devel" repository and type "fakeroot apt-get install libqt4-maemo5-dev". Qt will be installed to "/opt/qt4-maemo5". The long story can be found on the wiki.

The source code repository is still at http://qt.gitorious.org/qt/x11-maemo. Check out "README.maemo5" for build instructions.

How to contact us?

You can reach us via the "qt-maemo-feedback" mailing list (see Mailing List instructions), or on the "#qt-maemo" IRC channel on irc.freenode.net. For bug reports, you can use our bug tracking system at http://bugreports.qt.nokia.com/. Please set the bug's component to "Maemo 5".

Disclaimer

It's a Technical Preview. Treat it as such :)

How to debug

The gdb 6.8 that is currently shipped with the Maemo 5 SDK is crashing a lot when trying to debug Qt applications. We packaged gdb 7.0 for scratchbox (ARM and x86 targets), you can find the packages here: http://chaos.troll.no/~harald/gdb7/. gdb 7.0 is installed as "gdb7" (note the "7" suffix) to /usr/local/bin, so it won't clash with the existing gdb. If the standard gdb crashes, give our gdb7 a try.

What'll happen next?

• Much more documentation (sorry for the lack of it)
• Pickers for date and general single selection QAbstractItemModel picking
• Kinetic scrolling also for QWebView
• Fine tune the layout and widget metrics and spacing
• A Qt for Maemo 5 Beta once we're feature complete and have better test coverage

(*) Note that there are currently still some rendering glitches with the OpenGL ES 2 graphics system which we're currently investigating.