After a few delays, the PR 1.2 firmware for the N900 is finally released with Qt 4.6.2 shipping by default (see maemo.org for all PR 1.2 related info). This means that all the apps that up until now only ran in the SDK can finally be deployed to real devices

The final Qt packages have the version tag 4.6.2~git20100401-0maemo1+0m5 (no April Fool’s, despite the date).

Some useful information:

• A good starting point for developing with Qt for Maemo 5 is the Nokia Qt SDK.
• Here’s the Qt for Maemo 5 documentation, suggested reads are the Maemo 5 introduction page and the Maemo 5 platform notes.
• The Qt for Maemo 5 examples can be found in Maemo’s extras-devel repository. The package is called libqt4-examples-maemo5 and installs to /usr/examples/maemo5. Documentation is here.
• The Qt 4 wiki contains useful information about building, debugging, running and deploying Qt apps.
• Here’s the git repository, contributions are welcome

What’s next

If you follow the git repository, you can see that we’re working full-steam on Qt 4.7 for Maemo 5. Experimental packages will appear soon in the extras-devel repository.

Update

4.7 packages are now in Maemo’s extras-devel repository. In the Scratchbox based SDK, type apt-get install libqt4-experimental-dev to get the libs and headers.

Happy app creation

The Qt 4.7 Beta1 was released today, and I’m happy to announce that a set of experimental Qt 4.7 packages is available for Maemo 5 as well: http://chaos.troll.no/~harald/qt4-maemo5-4.7/20100505/ (all packages in one single tarball here).

Note: The packages now strictly require PR 1.2. Please only install them in the latest Scratchbox based SDK, which already ships a pre-release of PR 1.2. Once PR 1.2 is officially released (*), the packages can also be installed on the device. MADDE and Qt Creator support is pending.

Following a request from the Maemo community, the experimental Qt packages were renamed from libqt4-maemo5 to libqt4-experimental. The packages still install to /opt/qt4-maemo5, so they don’t clash with the device’s Qt. This ensures that installing the experimental Qt 4.7 packages won’t have bad side effects on existing apps.

How to install

We suggest to remove the old libqt4-maemo5 packages first:


fakeroot apt-get remove .\*qt4-maemo5.\*


After downloading the experimental packages, install them with the dpkg utility:

x86 Scratchbox target:

fakeroot dpkg -i *i386.deb


ARM Scratchbox target:

fakeroot dpkg -i *armel.deb


The road ahead

Once PR 1.2 comes with official support for the stable Qt 4.6.2 version, experimental Qt 4.7 snapshots will be pushed to the Maemo extras-devel repository. If everything goes well, the release after PR 1.2 will ship with Qt 4.7.x (where “x” is whatever patch release is available at that time).

Feedback and contact

As always, you can use the qt-maemo-feedback mailing-list (info) or the IRC channel #qt-maemo at irc.freenode.org to get in touch with us.

Happy experimenting!

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(*) Sorry, we don’t know the PR 1.2 release date either

More than a month has passed since the release of Creator’s 2.0 alpha release. The Berlin trolls were truly busy, not only with fixing reported bugs, but also by improving the overall developer experience. This beta is another milestone in the 2.0 release cycle, as we hope you will test-drive this release, to ensure 2.0 will be rock-stable, and to get to know the new features that were introduced.

If you recently typed apt-get update && apt-get dist-upgrade in your Scratchbox based Maemo 5 SDK, you might have noticed a large amount of packages flooding in - yes, PR 1.2 is near. Maemo.org is already full of PR 1.2 blogs, including a visual overview of the new features and the PR 1.2 Changelog.

This means that the time of the libqt4-maemo5-* packages has come to an end, please use and test the libqt4-* packages (4.6.2~git20100310-0maemo1+0m5), which now contain Qt 4.6.2+x in /usr/lib. To uninstall the old preview packages, just run apt-get remove libqt4-maemo5-\*.

Wait - Qt 4.6.2+x? Well, as with every Linux distribution, some smaller fixlets and features were backported. I’d like to highlight a few of them.

Up until now, kinetic scrolling was limited to 20 fps. This is a good default, since 20 fps look smooth, don’t drain too much battery and leave some CPU for background processes/threads (isn’t it nice to have multi-tasking?). However, for demo purposes, you might want to have 60 fps for that really, really smooth look, so we introduced the QAbstractKineticScroller::scrollsPerSecond property. Unfortunately, our camera cannot grab 60 fps, so no youtube video today

The second interesting feature is QAbstractKineticScroller::axisLockThreshold. Imagine that a user scrolls downwards in a QScrollArea. Now, unless he’s an android, he won’t manage to scroll down in a perfect line, usually it’s something like 100 pixels downwards and 5 pixels to the left. The axisLockThreshold property allows to lock the scrolling to the nearest X or Y axis. In our example, the 5 pixels to the left are ignored, and the view just moves 100 pixels down.

Finally, QAbstractKineticScroller::OvershootPolicy allows to set the overshooting behavior when scrolling. The default is to just do overshooting when a view is able to scroll in a particular direction. In addition to the default behavior, overshooting can now be completely disabled, or always forced on.

A note for everyone building Qt from sources - after you upgrade your SDK to PR 1.2, you should use the *-pr1.2 branches (e.g. 4.6-fremantle-pr1.2) to get the latest input method fixes.

Happy Easter Hacking