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To me, this seems like an interesting catalyst to learn a GUI API. Not only is cross platform is a welcome positive; the Qt structure is intriguing. Particularly see the Qt Object Model for a great read. I had little idea that Qt used a signals model and was tending towards strict use of the MVC paradigm. Perhaps comprehension of Qt would increase my chances of bothering to learn the almost entirely alien Cocoa/Obj-C rhetoric.

Huh, lack of decent freeware software? You are kidding right? There is a ton of decent freeware software (some is advertising supported, and some not).

I use Linux, OSX, and Windows, and if one thing can be said Windows has momentum BECAUSE it has all types of software freeware, and commercialware.

Developers on Windows will not use QT for their commercial apps. The main problem is the cost. http://www.trolltech.com/products/qt/pricing.html. You are talking anywhere from 3000 to 5500 USD. Those people doing shareware or freeware, and who DO NOT want to give out the sources will not invest that kind of money for an SDK. You still will most likely need to buy an IDE, and compiler. And the moment you purchase Visual Studio you don't need a GUI toolkit.

The argument of cross-platform does not spin either because it means a 5500 USD investment, which has to pay off. If were doing cross-platform using C++ I would use either GTK, or wxWidget.

On this page: http://www.trolltech.com/download/opensource.html it says

Can I use the Open Source Edition to write commercial software?
Only if you plan to publish the software exclusively under the GPL.
If you plan to release a commercial product either using closed source or a mix of closed and open source licensing, you must use the commercially licensed version of Qt.

As I understand it, the GPL gives me the right to incorporate Qt into a commercial (and GPL'ed) product and they can't tell me otherwise since Qt is distributed under the GPL. Am I wrong? Does TrollTech have the right to tell me I can't make a commercial GPL product with Qt?

The legal jargon surrounding the use of scripting languages and Qt is still kind of vague. Buried very deep in their FAQ section is the question Can I develop commercial applications with PerlQt or PyQt or other Qt wrappers? which isn't that helpful.

It still doesn't discuss in-house applications that are meant to solve production needs, but will never be sold or given away because the code is: too customized, reflects a particular business model, and/or not well polished. Perl/Qt is so much better than Perl/Tk, but we tolerate Tk because it's free.

Now I don't object to the core developer of applications needing a license, since that is what corporations do with Visual Studio, but scripted languages is kind of fuzzy. I think the best way to solve this is to officially support some of the language wrappers, like Perl and Python and provide some mechanism that determines an elegant way to "lock the interface layout" unless a developer license can be had. For example, only precompiled QtDesigner User Interface files could be added run-time, or something like that.

Then distribute it with ActiveState's ActivePerl or ActivePython. That version would only allow GPLed applications to be built, maybe through a variable like $main::LICENSE="GPL" to be declared, or something like that. You would have to purchase ActivePerl Pro Studio in order to develop commercial applications with the Qt widget set, but again the same "lock it down without a license" could be had.

Official support for scripted languages is the only way to sort out the need for quick, small programs for which C++ is inappropriate.

3) The commercial license is very affordable.

The guy who did most of the icons for the new Qt Tools is one of us. He's a pretty cool dude, once you get past the ego and the constant attempts at world domination.

Though Google themselves may not provide it.

How long will it be, really, before someone either reverse-engineers (or Google provides?) the queries and data that go back and forth? It seems pretty obvious that all of the data is kept server side, and the download for the Windows(tm) version of the application seems to only be about 10MB or so (so I'm guessing - and it IS only a guess - that there's not a lot of processing that the client side has to do).

QT has OpenGL classes in it, doesn't it? How long before there's a "KGoogleEarth" project?...

Yes, you can access X-terminal or run OpenOffice. This mobile (and the new generation of Motorola Linux-based phones) use Qtopia: Phone Edition...

That's Apple's fault: they are putting roadblocks in the way of people trying to do a better job with X11 integration on Macintosh.... There is no technical reason why X11 couldn't be as smoothly integrated into OS X as Carbon and Cocoa are....they probably are afraid that if X11 becomes well enough integrated so that people can write applications with a native L&F, it would become the predominant API on OS X.

The OOo developers got so annoyed with Apple's behavior that they stopped working on Macintosh integration.

X11 should... run automatically on every Macintosh

Just in case you've been hiding under a rock the past few years: QT has already been relicensed under your choice of the GPL and Trolltech's own QPL. See http:///developer/faqs/license_gpl.html for details.

Just in case you've been hiding under a rock the past few years: QT has already been relicensed under your choice of the GPL and Trolltech's own QPL. See http:///developer/faqs/license_gpl.html for details.

Not a rumor ;)

QT 4 announcment

They seem to think that they're being fair..
http://www.trolltech.com/company/model.html

With the exception of java most libraries don't seem to be as complete a cross platform solution. There are other solutions, they're just trying to make a quality cross platform solution, there are alternatives, but you have to collect the parts and put them together yourself, and test etc...

There is GTK which is cross platform for windowing and widgets. (GNOME is built on this)

If you don't like it don't buy it, but I love the irony of software developers whinning about software prices (or pirating for that matter).

The very strong rumour is that Qt 4.0 will be GPL for Windows.

Since when is an official press release a "very strong rumour"?

Qt 4.0 WILL be GPLed. There's no "rumour" about it.

10 LET M$="Microsoft"
20 REM Please don't mention Penny Arcade until you try fitting "Microsoft" into the subject line

but rather the practice of trying to support completely alien systems that don't implement the common interfaces you normally depend on. This kind of "portability" often results in a huge festering pile of kludges and massive duplication of code. A popular example is MS-DOS; many packages end up with ".bat" files duplicating their makefiles, use painfully awkward filenames to avoid upsetting 8.3 filename restrictions, have special cases for MS-DOS scattered throughout the code, etc.

True, making an app portable between *n?x and Microsoft's "finest" used to take a lot of convoluted bullmanure to get right, but Windows 4.0 and up (95, nt4, 98, 2000, me, xp) have cleaned up. The file system supports file names longer than the Mac ever did. Developers can use MinGW+Msys, a reasonably complete port of the GNU compiler toolchain (yes, including GNU Make) to the Windows runtime library. And the popular Free GUI toolkits from *n?xland (wxWidgets, GTK+, and now Qt) are available on Windows as well.

Also take a look at Qt, this is used for building KDE apps, among others. It's got very good documentation. I also like Eclipse's SWT framework if you want to use Java.

http://www.trolltech.com/developer/affiliations.ht ml

Depends on which Version you take...

So for a single platform, it would be $1790 and $2880

The biggest selling point to me, by far, is the superb documentation. Compare the documentation for, say, QString http://doc.trolltech.com/4.0/qstring.html against the complete awful docs you get for borland c++ etc.

Since the GPL doesnt allow for distribution of code under any other license, then its not compatable with any other license.

"Why do developers choose to write these great apps with GTK instead of QT?"

Actually, I'll reproduce a portion of this article from http://wiki.wxwidgets.org/wiki.pl?WxWidgets_Compar ed_To_Other_Toolkits

It certainly captures why I use WxGTK over Qt.

wxWidgets compared to Qt

* Both Qt (http://www.trolltech.com/) and wxWidgets have many non-GUI-related classes, such as date/time, containers, networking and OpenGL functionality. However, if you are developing commercial applications (non-gpl) in Qt and want to use most of these classes (including the OpenGL widget), you have to pay extra for the "enterprise edition" (http://www.trolltech.com/products/qt/editions.htm l) on top of the normal commercial version of Qt (the "professional edition").

* Qt2 is available under the GPL for open-source applications, and under the QPL for commercial applications. Qt3 for Mac and GNU/Linux is similarly dual-licensed, but there is no free version of Qt3 for Windows. All ports of wxWidgets are distributed under a permissive modified (but explicitly OSI-approved) LGPL.
o Trolltech has announced that Qt4 will be available under the GPL on Windows. See http://www.trolltech.com/newsroom/announcements/00 000192.html.

* Qt doesn't have true native ports such as wxWidgets ([with the exception of Qt/Mac].) Qt draws its own widgets on each platform instead of using the native widgets, whereas wxWidgets offers true native ports for all the supported platforms. Additionally, an approach similar to Qt's is achieved with wxUniversal (of course it should be noted that on some platforms, Qt _is_ the native GUI library.)

* Qt programs are not true C++ programs and require a special pre-compiler, the so-called Meta Object Compiler or moc. wxWidgets programs do not require this kind of preprocessing and are true C++ programs.

* Qt is used by several large projects like KDE and the Opera browser (on the other hand, wxWidgets is used by projects like the AOL Communicator)

* Qt makes extremely liberal use of virtual functions (QTWidget, the base class of all widgets in Qt had 91 at last count), giving it a more OO design than wxWidgets (which uses a more MFC-like approach using macros). What this means is fewer lines of code in general when using Qt, but faster execution speed when using wxWidgets (although the degree to which this occurs depends on whom you ask).

"Why do developers choose to write these great apps with GTK instead of QT?"

Actually, I'll reproduce a portion of this article from http://wiki.wxwidgets.org/wiki.pl?WxWidgets_Compar ed_To_Other_Toolkits

It certainly captures why I use WxGTK over Qt.

wxWidgets compared to Qt

* Both Qt (http://www.trolltech.com/) and wxWidgets have many non-GUI-related classes, such as date/time, containers, networking and OpenGL functionality. However, if you are developing commercial applications (non-gpl) in Qt and want to use most of these classes (including the OpenGL widget), you have to pay extra for the "enterprise edition" (http://www.trolltech.com/products/qt/editions.htm l) on top of the normal commercial version of Qt (the "professional edition").

* Qt2 is available under the GPL for open-source applications, and under the QPL for commercial applications. Qt3 for Mac and GNU/Linux is similarly dual-licensed, but there is no free version of Qt3 for Windows. All ports of wxWidgets are distributed under a permissive modified (but explicitly OSI-approved) LGPL.
o Trolltech has announced that Qt4 will be available under the GPL on Windows. See http://www.trolltech.com/newsroom/announcements/00 000192.html.

* Qt doesn't have true native ports such as wxWidgets ([with the exception of Qt/Mac].) Qt draws its own widgets on each platform instead of using the native widgets, whereas wxWidgets offers true native ports for all the supported platforms. Additionally, an approach similar to Qt's is achieved with wxUniversal (of course it should be noted that on some platforms, Qt _is_ the native GUI library.)

* Qt programs are not true C++ programs and require a special pre-compiler, the so-called Meta Object Compiler or moc. wxWidgets programs do not require this kind of preprocessing and are true C++ programs.

* Qt is used by several large projects like KDE and the Opera browser (on the other hand, wxWidgets is used by projects like the AOL Communicator)

* Qt makes extremely liberal use of virtual functions (QTWidget, the base class of all widgets in Qt had 91 at last count), giving it a more OO design than wxWidgets (which uses a more MFC-like approach using macros). What this means is fewer lines of code in general when using Qt, but faster execution speed when using wxWidgets (although the degree to which this occurs depends on whom you ask).

"Why do developers choose to write these great apps with GTK instead of QT?"

Actually, I'll reproduce a portion of this article from http://wiki.wxwidgets.org/wiki.pl?WxWidgets_Compar ed_To_Other_Toolkits

It certainly captures why I use WxGTK over Qt.

wxWidgets compared to Qt

* Both Qt (http://www.trolltech.com/) and wxWidgets have many non-GUI-related classes, such as date/time, containers, networking and OpenGL functionality. However, if you are developing commercial applications (non-gpl) in Qt and want to use most of these classes (including the OpenGL widget), you have to pay extra for the "enterprise edition" (http://www.trolltech.com/products/qt/editions.htm l) on top of the normal commercial version of Qt (the "professional edition").

* Qt2 is available under the GPL for open-source applications, and under the QPL for commercial applications. Qt3 for Mac and GNU/Linux is similarly dual-licensed, but there is no free version of Qt3 for Windows. All ports of wxWidgets are distributed under a permissive modified (but explicitly OSI-approved) LGPL.
o Trolltech has announced that Qt4 will be available under the GPL on Windows. See http://www.trolltech.com/newsroom/announcements/00 000192.html.

* Qt doesn't have true native ports such as wxWidgets ([with the exception of Qt/Mac].) Qt draws its own widgets on each platform instead of using the native widgets, whereas wxWidgets offers true native ports for all the supported platforms. Additionally, an approach similar to Qt's is achieved with wxUniversal (of course it should be noted that on some platforms, Qt _is_ the native GUI library.)

* Qt programs are not true C++ programs and require a special pre-compiler, the so-called Meta Object Compiler or moc. wxWidgets programs do not require this kind of preprocessing and are true C++ programs.

* Qt is used by several large projects like KDE and the Opera browser (on the other hand, wxWidgets is used by projects like the AOL Communicator)

* Qt makes extremely liberal use of virtual functions (QTWidget, the base class of all widgets in Qt had 91 at last count), giving it a more OO design than wxWidgets (which uses a more MFC-like approach using macros). What this means is fewer lines of code in general when using Qt, but faster execution speed when using wxWidgets (although the degree to which this occurs depends on whom you ask).

And what is the trolltech QT problem?

Why the GPL License for PC-BSD Installer?

All custom software developed for PC-BSD, The GUI Installer, Package Manager, Package Creator, were developed using the QT libraries. (www.trolltech.com) QT is one of the most powerful, solid C++ library sets available today, but it does not allow releasing under the BSD license, only under the GPL, or their own custom license QPL. For this reason, we have chosen to go the GPL approach. This was not intended to *pollute* the BSD license, just as a user running KDE on BSD doesn't intend to pollute the license either.

Why the GPL License for PC-BSD Installer?

All custom software developed for PC-BSD, The GUI Installer, Package Manager, Package Creator, were developed using the QT libraries. (www.trolltech.com) QT is one of the most powerful, solid C++ library sets available today, but it does not allow releasing under the BSD license, only under the GPL, or their own custom license QPL. For this reason, we have chosen to go the GPL approach. This was not intended to *pollute* the BSD license, just as a user running KDE on BSD doesn't intend to pollute the license either.

...'coz the situation won't last since TrollTech improved the rules for the Win32 version of their Qt libraries.

...'coz the situation won't last since TrollTech improved the rules for the Win32 version of their Qt libraries.

...'coz the situation won't last since TrollTech improved the rules for the Win32 version of their Qt libraries.

...'coz the situation won't last since TrollTech improved the rules for the Win32 version of their Qt libraries.

Roms based on openzaurus with an updated qtopia-2.1.1, that will sync with Linux, Mac OSX and Windows are available for the sl6000, as well as other Zaurus including the a300, from Trolltech's new Qtopia Community web site:
http://www.qtopia.net

It doesn't hurt the linux support that Opera and Trolltech have offices in the same building in Oslo, Norway either.

http://www.opera.com/company/
http://www.trolltech.com/contact/index.html

Easy! Dual licensing!

UIML is a subset of the XML-language for implementing platform- and programming-language-independent user-interfaces.

Maybe you should have a look around, whether there is a good UIML-renderer for Java.

If your research is into this topic, you may even want to develop a UIML-renderer for Java yourself! I'm sure many people would be interested in an open-source project with this aim.

I am using Qt (with C++) and qt-designer myself, which is using a proprietary XML-format for rendering user-interfaces (ui-files).

References:

UIML-tools

Qt-Designer

Qt user-interface renderer

Mozilla user-interface renderer

UIML is a subset of the XML-language for implementing platform- and programming-language-independent user-interfaces.

Maybe you should have a look around, whether there is a good UIML-renderer for Java.

If your research is into this topic, you may even want to develop a UIML-renderer for Java yourself! I'm sure many people would be interested in an open-source project with this aim.

I am using Qt (with C++) and qt-designer myself, which is using a proprietary XML-format for rendering user-interfaces (ui-files).

References:

UIML-tools

Qt-Designer

Qt user-interface renderer

Mozilla user-interface renderer

"we represent as open-source friendly a commercial organization as you are *ever* going to see"

"Unlike the Marine corp, the open source community is more than willing to ignore their bad apples as 'not my problem' (the Marine corp punishes the group for the behavior of the bad apples, pretty soon there are no bad apples)."

Larry suggested, "if Linus and Andrew and the others moved elsewhere, we'd glady comp them licenses", referring to their current employment with OSDL.

"closed source has no real advantage on open source." -->Except for that little thing called "Developers getting paid"...

Since when does being "closed-source" mean "getting paid"? Yes, many companies base their model on closed source. Many others base their model on open source, and make plenty of money.

So wake up and smell the coffee! Times change, and your FUD-like statements are just so provably wrong.

Didn't you see the article yesterday on how open source drives down the cost of startup?

Don't imply F/OSS isn't good for business. It's just not good for your limited understanding of business.

"Now there's even a GPL full version for Windows"

Since when?

http://www.trolltech.com/download/opensource.html

OpenGL on all platforms

PostScript on Linux, Unix, and Mac OS X

QuickDraw and CoreGraphics on Mac OS X

X11 and the X Render Extension on Linux and Unix systems

QVFb, VNC and LinuxFb on Qt/Embedded

GDI and GDI+ on Windows

That's fine if all you want to do is program for the Mac. Most people want to program either for windows or multiple operating systems.

You can either program in C++ using the STL and then isolate modules of GUI code in Cocoa, or program in QT.

It's useless for python or ruby.

xCode is a programming environment. You're talking about scripting.

QT has been GPLed on Windows. It happened a few weeks/a month ago. Don't have the URL but it was slashdotted...

Oh right, google, here it is.

Q: Why did you change the name of the Qt Open Source Edition?

A: The purpose of changing the name from "Qt Free Edition" to "Qt Open Source Edition" is to clarify the intention behind this edition.

Trolltech is a strong believer in Open Source development. We are proud to support the KDE project and many other Open Source projects. We support the idea of Free Software.

However, some people interpreted the "Free Software" as meaning purely free of charge, without any obligation to make source code available. We wanted to avoid encouraging this interpretation.

Q: Why do I need to buy a commercial edition when I can get it for free?

A: If you want to develop Open Source Software, you are welcome to use our Qt Open Source Edition. If you don't want to develop Open Source Software (for example to keep your source code secret or to produce commercial software), you must purchase a commercial edition of Qt.

Q: I don't want to give away my source code. What do I do?

A: You must buy a commercial Qt license.

If you use their framework to develop opensource projects, you qualify for their OpenSource Edition License. However, if you want to keep the sources all to yourself you can, but it will cost.

This allows Trolltech to make money and stay in business while still supporting the FOSS community.

If you use their framework to develop opensource projects, you qualify for their OpenSource Edition License. However, if you want to keep the sources all to yourself you can, but it will cost.

This allows Trolltech to make money and stay in business while still supporting the FOSS community.

If you use their framework to develop opensource projects, you qualify for their OpenSource Edition License. However, if you want to keep the sources all to yourself you can, but it will cost.

This allows Trolltech to make money and stay in business while still supporting the FOSS community.

A counter-example (and an interesting business approach) is trolltech:
They created the QT library, and they are giving it away under GPL. They make a profit from companies that need the library for non-GPL products.

An argument might be made that things would go even faster (and they are already amazing fast) for KDE if the team got control of GPL Qt development. But things are going nicely as they are.

Philosophically the partnership between KDE and Qt seems (again, just my ignorant opinion) quite ideal however. Unlike the various Gnome corporate sponsors, who seem to me to be always mostly interested in "patching things up" in various areas, the focus of Qt to commercial demands at designing a strong design and key features has provided KDE an awesome base.

By the way TrollTech is GPL'ing the new Windows version... so once again, just like when they GPL'd the X version, there is one less argument against Qt... though that argument has always been mostly irrelevant and just a point of political pique. (And i see ignorant people on this thread still making the old non-GPL throat warbling FUD...)

Other tidbits... QTopia 2.1 is open source. Opera is the fastest browser. Apple chose KHTML over Gecko. SuSe rocks... but personally i use Gentoo and FreeBSD.

For GUI, you may also want to look into Qt (http://www.trolltech.com/). It's a free library, and can create windows for X, Windows, and the Mac. Code-wise, it seemed to me to be a short learning curve, I learned enough to write a few simple GUI applications in just a couple weeks. My only complaint is that the Windows version doesn't look quite right, some of the widgets are a little different from the native set.

.Net isn't a GUI development solution. There's a lot of different resources out there for understanding what it is, but you can start here with the basics.

Thank you, King Obvious. I was obviously talking about the GUI libraries and RAD tools available for .NET.

but from what I can see, it's Python-based. That's fine if you know Python (and I do), but not everyone does

Qt is a C++ library usable from many languages. PyQt is its Python bindings. Not everyone does, but everyone should, because it is the right language for GUI and most of the other non-performance-critical applications.

VS.Net offers 3 or 4 different development languages that easily work together.

Besides for Python.NET, the rest are statically typed and otherwise very difficult to program in (compared to Python, ofcourse) and thus a very poor choice for high-level code such as GUI code.

YOU like PyQt/PyKDE, but that doesn't make it "far better" for everyone's purposes. It just means that you like it.

No, PyQt/PyKDE are better objectively in terms of API consistency, simplicity, power and expresiveness.

When I like something I say I like it. PyQt/PyKDE are simply better than all Microsoft GUI solutions out there.

And your point is basically immaterial to the main thread: there's a ton of support and information for and about developing Windows GUI applications, that is, the full application chain from front-end to back, and there's a paucity of such information for Linux

That is because a ton of information is needed to program Windows GUI applications as the Windows API's are so horribly broken and difficult to use.

As for Linux lacking documentation (more accurately PyQt/PyKDE as those are portable to non-Linux systems unlike Microsoft GUI tools), I did try a Google search and this is the first result.

Note that this documentation, unlike the MSDN has a consistent format, is usable as a reference and as a tutorial and is comprehensive and complete uniformly across all aspects of Qt. Can you claim this about Microsoft's documentation?