Nokia's Maemo Switching To Qt

suka writes "During a keynote at the Gran Canaria Desktop Summit, Nokia's Quim Gil announced that a future release of Maemo is going to be built around Qt. Maemo Harmattan is going to switch away from GTK+ / Hildon, derStandard.at reports from the conference." Michael Pyne also writes with a post describing day one of the conference from a KDE perspective.

Comments

I wonder about this

[erroneus]

There is a lot of software for the Nokia N810 and below. Switching out to a new UI means a lot of stuff will either get uprooted or there will be a lot of libraries loaded into the machine's precious little memory.

Still, if the developers of software port over to the new environment quickly enough, it won't matter but I can't imagine things will be quick enough.

What can be done under Qt that can't be done under GTK? Is Qt more efficient in some way? What are advantages of Qt over GTK? I've never been clear on the differences... I just know they are different.

Re:I wonder about this

[shutdown -p now]

You forgot one thing: performance. Qt guys take it very seriously, and have numerous tests showing off just how fast their rendering and layout code is. I would imagine that, for resource-constrained devices, this can be a big deal.

Re:I wonder about this

[Kjella]

My main issue is that Qt is pretty strongly tied to C++, and I *despise* that language.

Did you try C++ with or without Qt? I must admit, I don't like C++ outside of Qt, it brings the whole platform to another level. QStrings and QByteArrays are a godsend compared to std::string and char *. Using the QObject system I easily write applications with no memory leaks because it will delete any child QObjects when it goes, making it easy even without amy garbage collector. Finally, using signals and slots makes your application more robust - screw something up and nothing will happen because the signal never reaches its destination but it won't crash hard on an invalid pointer. Granted, I've heard you can do the same with STL and boost and duct tape, but I never managed to do it.

Gtk+ is not Nokia's problem

[jipn4]

Nokia has its own lightweight GUI library that they use with Symbian--and their UIs suck. They have built applications with Gtk+--and their UIs suck. They have build Windows and OS X desktop apps--and their UIs still suck. I think the problem Nokia has with GUIs and software has to do with how they develop software, not whether they use Gtk+ or Qt.

Another problem with their choice is that it ties them to C++; the trend in mobile development, however, is towards other languages, like Javascript (Pre), Java (Android), Objective-C (iPhone), and C# (Windows Mobile). Only Symbian steadfastly clings to C and C++. That would be fine if Symbian actually ended up being the fastest and having the best UI of the bunch, but it's actually the slowest and least responsive of the bunch.

Qt uses only 'nice' parts of C++

[chris-chittleborough]

The Qt designers don't just create widgets etc, they design components that are easy to program with. As part of this, they avoid stuff that requires the tricky/ugly parts of C++. For instance, you rarely need to explicitly delete objects, because their libraries use reference counting to automagically delete objects at the earliest appropriate time.

So it is easy for any good programmer to learn enough C++ to use Qt effectively.

(Actually, Qt uses an extended version of C++, implemented via a preprocessor. The extensions provide "signals" (like no-op methods) and "slots" (methods which can be connected to signals), plus a limited-and-very-useful facility for run-time widget class information. As usual with Qt, these facilities are just extensive enough make it easy to do the things most people want to do, rather than trying to provide everything that anyone might want.)