Talk:Qt (software)

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Trolltech insiders pronounce Qt as "cute"[citation needed]

I don't know how to 'cite' this, but it is called that in their developer videos and anyone who has attended a QuickStart or Developer Day. I've witnessed it used in all three personally myself. 02:10, 29 August 2007 (UTC) scorp1us@yahoo

Is there any reason to write QT Toolkit instead of just Qt? The program is called Qt, not QT and if the toolkit-attribute is needed we could call it Qt toolkit, but I don't think it has to be. BTW: The company calls itself Trolltech, not Troll Tech or TrollTech.

Fixed. It is now "Qt", also I fixed the spelling of Trolltech, thanks. -- mkrohn 23:40 Mar 31, 2003 (UTC)

-Generally QT refers to QuickTime (Apple, Inc), so Qt is used to avoid confusion 02:10, 29 August 2007 (UTC) scorp1us@yahoo

I think there is. Okay, the GTK toolkit could be called just GTK here. But what about the Harmony toolkit? Wikipedia will become immense, so I think it's important to be as precise as possible, also in naming. (Although I haven't followed naming convention discussions, so I don't know what the consensus is). (Also, the original article wasn't mine.) -- Zork

Harmony is no more. However, why do you call it QT_Toolkit instead of Qt_Toolkit

correct, I have added this to the Harmony project page. -- mkrohn 23:40 Mar 31, 2003 (UTC)

I'm not sure this belongs in Category:X Windows Systems; it's really a portable toolkit. DJ Clayworth 14:57, 30 Jun 2004 (UTC)

I'm thinking from the viewpoint of the category, not of the article. It's a major toolkit used on X - David Gerard 15:08, 30 Jun 2004 (UTC)

IDE ?[edit]

Is this an Integrated Development Environment?--Jondel 02:42, 18 Nov 2004 (UTC)

No, it is not an IDE. --Yamla

Status of Font Support?[edit]

Could someone please add how good Qt supports various font related features (OpenType like in, Bidi, etc.). I guess that what Scribe is about?

QT GPL version vs proprietary version[edit]

Removing this line: Note that the open source edition is restricted to open source non-commercial development only [1].

First, I removed non-commercial, since of course GPL software can be commercial. Then I realized that the remainder was duplicative of what the GPL already says. The complications of describing what Gerv mentions are beyond the scope of this article. It's cool, tho, so I stuck it into links.

Novalis 22:28, 14 Feb 2005 (UTC)

I have updated the history of Qt, to include the big events: inclusion of the Mac Os X version, GPLing of the Mac version and GPLing of all versions.
I am hesitant about how to refer to Windows the platform. Is it Windows, windows or always Microsoft Windows ?
Philippe Fremy

Requested move[edit]

Qt toolkitQt – {Qt is known as Qt, not "Qt toolkit". QuickTime is QT, not Qt. So there is no confusion.} — minghong 10:31, 28 Mar 2005 (UTC)

Add *Support or *Oppose followed by an optional one sentence explanation and sign your vote with ~~~~
  • Oppose-- PBS 11:37, 28 Mar 2005 (UTC)
  • Oppose - see my suggestion below. violet/riga (t) 17:53, 31 Mar 2005 (UTC)

Alternative proposed move[edit]

violet/riga (t) 17:53, 31 Mar 2005 (UTC)

  • Support. I very much agree with this suggestion. -- mkrohn 20:39, 31 Mar 2005 (UTC)
  • Support -- PBS 17:34, 1 Apr 2005 (UTC)


The alternative proposal has been accepted and implemented. violet/riga (t) 17:51, 2 Apr 2005 (UTC)

Qt license history[edit]

This section seems to be inaccurate, and contradictory:

"This gave rise to two efforts: the Harmony toolkit which sought to duplicate the Qt Toolkit under a free software license and the GNOME desktop that was meant to supplant KDE entirely. The GNOME Desktop uses the GTK+ toolkit which was written for the GIMP, and mainly uses the C programming language."
"Trolltech licensed the first version of Qt under the Q Public License (QPL), a free software license, but one regarded by the FSF as incompatible with the GPL."

According to documentation the FreeQt license (wasn't free software or open source) was used for Qt 1.45 and earlier), and the QPL only introduced with Qt 2.0. - Motor (talk) 08:48:25, 2005-08-12 (UTC)

BTW: The article would really benefit from a simple "stable versions" table:

Version Date Information
2.0 xxxxx Introduction of the QPL etc etc.

If anyone would like to investigate the details... - Motor (talk) 11:11:44, 2005-08-12 (UTC)


Article says: "Other portable graphical toolkits have made a different design decision, such as wxWidgets, MFC (Windows only), GTK+, and the Java based SWT[2] which use the toolkit of the target platform for their implementation."

Gtk+ uses "the toolkit of the target platform"? Huh?

Yes this is definitely not true for GTK+, but you could add AWT to the list.... also it's pretty obvious that an one-platform toolkit like MFC uses native widgets...

Peer review of a related article[edit]

I submitted X Window core protocol for peer review, as I intend to candidate it for featured status. I would appreciate comments (Peer review page). - Liberatore(T) 18:07, 21 February 2006 (UTC)

open source and free software[edit]

Since there seems to be some confusion from the Nord on how the English language works, I'll lay it down for you all here. Open source means the source is available, this is not a point of view, this is the broadest definition of the term, the Open Source Initiative's definition of Open Source Software differs from this, it is however only their opinion and thus their point of view. In the same manner, free software is software which is made available for free, and while the Free Software Foundation defines free software differently, this is only their opinion and not the meaning of the words. Since Egil seems so confused and unwilling to perform the simple task of reading already available information in the open source article, perhaps he will take the time and exert the effort to read it here. 08:06, 25 March 2006 (UTC)

The early QT license is not open source according to the Open Source Definition, so using the term open source would be disputed, and certainly claiming a point of view. An outright claim that this license is open source is against WP:NPOV policy. By your name-calling in the edit summaries, you are also breaking the Wikipedia:No personal attacks policy. -- Egil 13:07, 25 March 2006 (UTC)
I could care less about the OSI's point of view. The term means open and so is valid, you're removing it is a POV. 20:36, 25 March 2006 (UTC)
An anon, User:, probably the same person as the above, keeps on changing the paragraph on Qt versions up to 1.45 into:
Until version 1.45, source code for Qt was released under the FreeQt license — which, while both free and open source, was viewed as neither open source nor free software by the Open Source Initiative and Free Software Foundation because while the source was available it did not allow the redistribution of modified versions
this time with the comment: (Around here, we do not apply people nor organizations' points of view - therefore the point of view of the Open Source Initiative does not belong here
This anon user has either not read the WP:NPOV principle, is not capable of understanding it, or is trolling. I am leaning towards the latter, but I'm tired of this, and would greatly appreciate the help and opinions of others. Egil 23:06, 1 April 2006 (UTC)

In my view, the anon's version is definately a bit POV but OTOH the version with the OSI stance is a bit excessive - i.e. it could use a bit more support of the TT view - i.e. perhaps instead of just "which, while both free and open " you could say that it claimed to be that (if it did claim to be that, that is). In other words, a bit of attribution towards the TT side should balance it out. Just another star in the night T | @ | C 00:19, 2 April 2006 (UTC)

Where is it my English is failing? The stuff was free, you could download it for free. The stuff was open source, the source code was open for viewing. The point of view of the Open Source Initiative adds in special restrictions to their version of Open Source Software, in the same manner as the Free Software Foundation does with Free Software. One cannot simply declare a new meaning for a word, the English language is not directed by a few small committees looking to push their own agenda. 01:27, 2 April 2006 (UTC)
I'll try to explain. A NPOV statement, suitable for Wikipedia, would be:
1) X claims A, while Y claims B
The added requirement is that both X and Y, plus the claims A and B, fullfil the requirement for notability.
A POV statement of the above scenario, not acceptable for Wikipedia, would be:
2) While A is true, Y claims B.
Returning to the issue at hand, we cannot say "Until version 1.45, Qt was free and open" because that would make us claim a certain point of view in a matter we know is controversial, as in case 2. We could apply case 1, but then we need to find someone notable X that supports this view. Saying "An anonymous contributor to Wikipedia claims that Qt version before 1.45 were free and open" does not fullfill the requirement for notability. -- Egil 15:33, 2 April 2006 (UTC)
So, you're saying that we have to have a neutral point of view by saying, "Until version 1.45, the English language claims that Qt was free and open source, while the Open Source Initiative claims otherwise regarding hope open it's source was and the Free Software Foundation claims otherwise regarding how free it was." That's seems stupid. 17:17, 2 April 2006 (UTC)
Welcome to the world of encyclopedia writing! Egil 18:49, 2 April 2006 (UTC)

The OSI and FSF's definitions of Open Source and Free Software are the commonly accepted definitions. Any deviation from their definitions would be misleading. Perhaps it would be an amicable conclusion to state "... (according to the FSF's definition)", although I think if the words "free software" are linked, there's no need because readers can click through for details on what the terms mean. The English language is a set of components. When put together, the components can mean something other than the combination of the strict interpretation of the individual components. —midg3t 01:44, 25 March 2007 (UTC)

Bindings for C[edit]

The article mentioned that there are bindings for C, but where can these be found? I searched the web and did not come up with anything that seemed solid and well supported. Any ideas would be helpful. Perhaps it would even be possible to link directly from the article to bindings for the different languages? Filur 12:52, 17 May 2006 (UTC)

  • The C bindings are commonly used as a base to bind other languages. I'd not consider that a point worth including in the entry -- I'm just tossing it out as a point of information to help you track them down. 13:59, 15 August 2006 (UTC)
    • I spent quite some time trying to track them down, but came up with nothing useful. Where can the C bindings be found? Do they come from Trolltech or a third party? Thanks. Filur 15:09, 16 August 2006 (UTC)
      • The bindings are called QtC. You might be able to find them, but it's are essentially a dead project. This is to the best of my knowlegde, an oldish wiki entry on the subject is here [2] Esben 20:11, 6 July 2007 (UTC)

Citation needed to say moc is critised by "C++ community"[edit]

I think the paragraph starting

The use of an additional tool has been criticised by part of the C++ community...

Needs some sort of citation or justification. The phrase " 'moc'-ery of c++ " is clearly a value judgement (besides being essentially meaningless) and should surely be attributed to someone if indeed someone has ever said that.

Furthermore, the "C++ community" is a very vague term, since it is not clear who is included in this. Exactly who has made these critisms of Qt should be referenced. 20:41, 18 June 2006 (UTC)

Alternative toolkits such as GTK+ are available...[edit]

Alternative toolkits such as GTK+ are available under a more permissive free software/open source license, at the expense of less complete support for Mac OS X and Microsoft Windows.

I started to reword this sentence and add it to the preceding paragraph since 1) is skirts around the fact that Qt is not LGPL and has no GPL exception, 2) mentioning GTK+ doesn't make it any clearer, and 3) the rest is not relevant. By the time I was done I had removed it and rewritten the preceding paragraph.

I'm not sure if the rewritten paragraph even belongs, though. I think it could be just as easily removed, yet I expect that some will want mention of the "...commercial development requires the commercial license" bit. I understand that it first appears shockingly in violation of the GPL, but think of the same statement with commercial replaced with proprietary.

Trolltech maintains that proprietary development requires the commercial license.

Anyway, let me know if the changes bother anyone.--Hamitr 21:44, 20 March 2007 (UTC)

Proprietary software with GPL version of Qt[edit]

What if a proprietary application uses Qt, not by linking to it but using some other way of interprocess communication? It’s completely legal for Firefox to connect to an IIS-powered server, as well as for Outlook to send mail via an Exim server, so it seems to be possible to split an application into a proprietary back-end and a open source Qt-based front-end without violating the GPL. One might declare the front-end is compatible with any back-end that conforms to a certain protocol; and it isn’t the developer’s trouble that the only application implementing the protocol is their own proprietary program. This also has the advantage of having the community improve the front-end module.

Any comments? Roman V. Odaisky 18:28, 24 March 2007 (UTC)

  • The GPL is usually interpreted so that even if a developer jumps through hoops to avoid actually linking the code together (eg. using IPC), if the end result is the same — that the application is effectively useless without the GPL portion — it is considered an aggregate work and is covered by the GPL. To cover your examples of Firefox/IIS and Outlook/Exim, all four applications work perfectly well without any of the others — they are not dependent. —midg3t 01:28, 25 March 2007 (UTC)

In Russia, logo designs YOU[edit]

Is the resemblance of the Qt logo to a hammer and sickle on purpose, or has someone from Trolltech confirmed it as an accident? --Damian Yerrick (talk | stalk) 03:24, 30 July 2007 (UTC)

That resemblance seems very weak to me, even after getting the two logoes side-by-side. In any case, the QT logo is a rather obvious way write together a Q and a T, like the æ, which is a contraction of a and e. So I think we can rule out any connection to any (defunct) regime. I also doubt that any trolltech employee would stoop to actually comment on this. Esben 10:24, 30 July 2007 (UTC)
Consider this a comment from an employee, as far as I'm aware, it was entirely unintentional, and even unknown until I'd read this statement. —Preceding unsigned comment added by (talk) 10:32, 12 November 2008 (UTC)

New licence exceptions for Qt 4.3.1[edit]

Starting from Qt 4.3.1, Qt lists a long list of linking exceptions for the GPL. It seems you are now able to link most Open Source licenced software with Qt. I think that warrants an update of that section in the article. See

Windows and Open Source[edit]

The open source editions of Qt 4.3.2 and above now support visual studio in as much as they officially work with the compiler, and qmake can generate visual studio projects ( - there is however no IDE integration in the open source edition. There's no official binaries for this option though - Qt needs to be built from source. —Preceding unsigned comment added by (talk) 00:44, 24 November 2007 (UTC)

Trolltech not acquired yet by Nokia[edit]

> which was acquired by Nokia on January 28, 2008

On this date both companies announced the plans for the acquisition, but the process has just started. The Trolltech stakeholers are today as owners of the company as they were last week. —Preceding unsigned comment added by (talk) 07:29, 29 January 2008 (UTC)

Refering to wxWidgets[edit]

In the design section , why there is a refer to wxWidgets?! it's supposed to be in the "See Also" section not within the article as that's seems to be ads from it's designers!!

VMware server 2.0[edit]

VMware server 2.0 rc1 for management uses Java toolkit not QT. I analyzed all binary and library in the Linux package RC2 downloaded today with 'nm', and there are no call to QT. But there are a lot of call to GLib/Gobject library, that are also packaged toghether. The 'vmware' executable, start a browser to and run the java interpreter. To me the management console is a Java applet. Where you "" found that "# VMWare Server, a PC virtualization application, Qt frontend since version 2.0" citation? --Efa2 (talk) 23:48, 17 September 2008 (UTC)

Thanks, I removed the line. If it really was written in Qt, someone can cite it. — FatalError 00:42, 18 September 2008 (UTC)

Trolltech vs. Qt Software[edit]

The article switches back and forth between referring to Qt's authors as Trolltech and as Qt Software, as I note their own website does, as well. Is there a particular reason for this? The article's rather confusing as it stands right now. If no one objects, I'm going to add a clarification to the introductory paragraph to the effect that the company's still referred to by its old name, or else update all references to Trolltech in the body of the article to Qt Software. (talk) 01:18, 6 November 2008 (UTC)

Trolltech as an entity will exist for up to a year after purchase by nokia (to support contracts signed under the name of Trolltech AS). Internally, it is Qt Software. The article should reflect this throughout, and any mentions of "trolltech" should only be in a historical perspective. A bit of side info, this name was decided upon by a vote of the employees. Sadly, I don't have any citations on that. —Preceding unsigned comment added by (talk) 10:39, 12 November 2008 (UTC)

Earliest USENET reference?[edit]

A cursory glance reveals http group/comp.os.linux.announce/msg/ba2a4d4efc9fe910?dmode=source&output=gplain ... though there could be earlier ones? (talk) 20:01, 26 February 2009 (UTC)

list of bindings[edit]

Given that Nokia has been getting more aggressive in creating bindings I think this should move from a sentence to a full list (with links) jbolden1517Talk 01:05, 2 April 2009 (UTC)


Should the screenshot top-right now be changed to Qt Creator (the new QT IDE)? CharlesC (talk) 10:20, 12 May 2009 (UTC)

Qt Jambi not stopped[edit]

At least from looking at the Qt Jambi page, it seems as if there are still new versions being released.

So that remark is wrong.

If you spot an error in the article, feel free to fix it yourself :). Regards, decltype (talk) 18:48, 31 October 2009 (UTC)

Non operational link[edit]

C++ GUI Programming with Qt 4/first edition. (2nd last link) does not work as of 20:29, 23 November 2009 (UTC) —Preceding unsigned comment added by (talk)

Requested move: Qt (toolkit) → Qt (framework)[edit]

The following discussion is an archived discussion of a requested move. Please do not modify it. Subsequent comments should be made in a new section on the talk page. No further edits should be made to this section.

The result of the move request was: Page moved. Ucucha 17:17, 1 February 2010 (UTC)

Qt (toolkit)Qt (framework) — I suggest to move Qt (toolkit) to Qt (framework) as Qt is not just a toolkit, it also can be used to create non-gui apps. From Qt's official website:

"Qt – A cross-platform application and UI framework"

I believe that the word framework is much more accurate than toolkit, in this case. What do other editors think? Thank you. —kedadial 16:26, 23 January 2010 (UTC)

The above discussion is preserved as an archive of a requested move. Please do not modify it. Subsequent comments should be made in a new section on this talk page. No further edits should be made to this section.

REQUEST: Moving the 'Applications' subsection to a separate list[edit]

I believe this is a wise move, seeing as there is too much, too long text here that can be comfortably read. As Qt becomes ever more popular, more popular are going to be created using the Qt framework. A good move would be to move the subsection of applications into a separate bulleted list. Yannis A 01:51, 14 February 2010 (UTC) —Preceding unsigned comment added by Johnanth (talkcontribs)

For this purpose already exists Category:Software_that_uses_Qt. Neurocod (talk) 23:10, 18 May 2010 (UTC)


An editor proposed to merge Qt Development Frameworks into this article more than a month ago, but did not seem to provide a rationale. I do not think a merge would be appropriate at this point, and will remove the tags - unless, of course, there are any objections or arguments presented in favor of merging. decltype (talk) 13:50, 23 April 2010 (UTC) I am also against merge . Melnakeeb (talk) 23:19, 28 June 2010 (UTC)

No merge. Wrapped in Grey (talk) 08:32, 14 July 2010 (UTC)

REQUEST: Bad Link[edit]

There is incorrect link to domain that is for sale, please remove it asap. -- (talk) 11:23, 15 June 2010 (UTC)


“commonly known also as "Q.T. (KYOO-TEE)"”

Is it possible to prove that, please?

I have never seen it spelled this way, with a dot after each letter.

Spidermario (talk) 16:28, 30 June 2010 (UTC)

Clarified. Wrapped in Grey (talk) 08:32, 14 July 2010 (UTC)

"Intel's MeeGo Touch"?[edit]

IINM, MeeGo Touch was developed at Nokia, not Intel. Having said that, it is Open Source, so perhaps Intel also contributed in some way, or forked it or something. — Preceding unsigned comment added by Davidmaxwaterman (talkcontribs) 03:36, 23 December 2010 (UTC)

Use of native UI-rendering APIs[edit]

Despite the phrasing on their web site, the actual source code does not bear this out. Qt still uses its own style engine to render everything down into pixels and bitblast that to the screen. They do not use native controls and use very little of the native platform's graphics API to render controls. Basically, this section is based on a stretching of the truth from a statement on the Qt web site and should be removed entirely. — Preceding unsigned comment added by Legalize (talkcontribs) 03:24, 5 January 2011 (UTC)

I disagree. Looking at Qt’s source code, it is clear that it uses native APIs. Even Windows Vista and 7’s transitions as well as Mac OS X’s are rendered. On Windows XP, a change in theme results in Qt applications taking the change into account. In GTK+ environments, the current theme is also used. I’m not sure whether how it is implemented matters, as long as applications look and feel native (as much as a cross-platform framework allows it). Spidermario (talk) 14:22, 5 January 2011 (UTC)
I looked at the source code for QTextControl. All the event handling, selection logic, etc., is implemented by Qt and not by using the native controls. The rendering is done the way Qt has always rendered widgets: by rendering them using their own style engine and then bit-blasting that to the screen. Please show me where it is using native APIs. Yes, they have re-implemented all the look-and-feel of the different platforms in order to get a native look and feel, although its subtly wrong sometimes because they don't actually use the native controls. Changing themes sends an event which Qt gets and updates its own style engine to reflect the theme change. I'm not disputing that Qt achieves a look and feel that's consistent with the platform, but it doesn't do this by using the native controls. It does it by re-implementing the look and feel itself. — Preceding unsigned comment added by Legalize (talkcontribs) 17:25, 5 January 2011 (UTC)
Indeed, after looking a closer look at the source code, I have to admit that you are right: Qt only reads theme informations (example). I think I kind of missed your point. Sorry. Spidermario (talk) 20:19, 5 January 2011 (UTC)
Qt does use the native theme APIs of the OS to render, that is draw, controls. This is done on at least the Mac (OS X) and Windows XP for most controls (QTextControl IIRC is an exception). Native rendering may also be used on other platforms (e.g. Gtk and Windows Vista) but I haven't had time to verify that.
I'll update the Qt article to reflect this as currently the article states that the native theme APIs are used only to 'query the platform for the desired appearance', which is not the whole truth. Qt doesn't only use native themeing APIs to get metrics; native theme APIs are also used to draw controls.
I will provide links to the actual source code for mac and winxp where the drawing is done. Focusing on QPushButton which is a push button control.
As has been stated in other comments Qt renders controls using implementations of the QStyle interface, e.g. QStyle::drawControl is used to draw bevelled push buttons when the ControlElement parameter is CE_PushButtonBevel, the documentation for the current release (4.8) is here [[3]]
Let's start with OS X, the default qstyle implementation on this platform is macstyle, the source code is here [[4]] QMacStyle::drawControl currently starts on line 3170, CE_PushButtonBevel case is handled on line 3380, HIThemeDrawButton is used on line 3414 to draw the control. HIThemeDrawButton is a native OS X function, it is part of the HITheme APIs which are part of the Apple Appearance Manager.
That is by default, on OS X, drawing of bevelled push buttons is done using native OS theme APIs. Most other controls are handled similarly.
Next Windows XP, the default qstyle implementation on ths platform is windowsxpstyle, the source code is here [[5]] QWindowsXPStyle::drawControl currently starts on line 1878, CE_PushButtonBevel case is handled on line 1942, 'flat' push buttons are handled in line 1966 which calls d->drawBackground, this either calls drawBackgroundDirectly or drawBackgroundThruNativeBuffer, both of these functions end up doing the drawing with pDrawThemeBackground or pDrawThemeBackgroundEx, these pointers are initialized on lines 353 and 354 like so:
346 QSystemLibrary themeLib(QLatin1String("uxtheme"));
353 pDrawThemeBackground = (PtrDrawThemeBackground )themeLib.resolve("DrawThemeBackground");
354 pDrawThemeBackgroundEx = (PtrDrawThemeBackgroundEx )themeLib.resolve("DrawThemeBackgroundEx")
That is the drawing is done by functions which are loading dynamically from "uxtheme", this is an OS library that provides the Windows Theme Manager Visual Style APIs.
Thus on both OS X and Windows XP controls are rendered using native OS theming APIs. Yes, there are some cases where this can't or isn't done, such as QTextControl, but those tend to be corner cases. In some cases the native OS theme APIs actually do quite complex rendering, e.g. on OS X default push buttons pulsate. That's the OS doing the animation, Qt is not emulating that. --ICouldBeWrong (talk) 21:04, 25 July 2012 (UTC)
The wording used to read "Complete abstraction of the GUI: Qt uses its own paint engine and controls. This makes the work of porting to other platforms easier because very few classes in Qt depended on the target platform. Qt used to emulate the native look of its intended platforms, which occasionally led to slight discrepancies where that emulation wasn't perfect. This, however, no longer applies because the latest versions of Qt use the native styles API of the different platforms to draw the Qt controls." This is a more accurate statement. Qt does use the native styles API to obtain the theme and style information needed for its own rendering engine to draw the control. However, it does not use the rendering of the native API, it still does its own rendering into pixels which it then copies to the screen. While using the style API allows Qt to get the information about GUI elements and draw them using its engine, its still not using the native controls to do the drawing. Any additional flourishes which are implemented by the native controls beyond generic styling must be re-implemented by Qt. This still leads to the imperfect emulation described in the original text. Its still an emulation, albeit an improved one. — Preceding unsigned comment added by Legalize (talkcontribs) 21:17, 5 January 2011 (UTC)

New Screenshot[edit]

Can we please get an up to date screenshot? —Preceding unsigned comment added by (talk) 10:37, 7 March 2011 (UTC)

Well, I don't have Qt Designer but looks like the screenshot is from version 4.4.3. Article says the latest version is 4.7. Have there been a lot of changes since version 4.4.3 that can be seen in a screenshot? Fleet Command (talk) 12:26, 7 March 2011 (UTC)

Nokia Sells the Qt Licensing and Services Business to Digia[edit]

According to this press release, Digia is buying part of Qt. I'm not sure who will own the Qt brand and such, and the stuff like or the Qt port of WebKit. After the Nokia+Microsoft deal, it seems things are changing a lot and Nokia will be "just" another Microsoft partner. I'm afraid about the future of Qt. As this is going to happen, someone should do a wikipedia entry for the Digia company too (wich currently provides lots of resources to Qt development but not mentioned here at all). (talk) 16:50, 7 March 2011 (UTC)

Right, it should be mentioned that Qt is struggling to stay alive. See this article.

grammar or rhetoric?[edit]

"The innovation of Qt when it was first released relied on a few key concepts"

What is the expression

"The innovation .. relied on "

to be thought to mean?

Try this for comparison:

"The election of Nixon when it first occurred relied on a few key promises."

This is a sort of passive construction nonsense characteristic of a certain kind of journalism, is it not?

In this case it relies on an ambiguity to suggest one sense of "innovation" while using the term in another sense. Who innovated and what was their innovation? Now it becomes a problematic assertion with regard to the facts concerning novelty and originality in a GUI Widget framework, library or architecture and needs some references to back it up given a multitude of other articles in wp. G. Robert Shiplett 21:57, 7 March 2011 (UTC)

LGPL vs commercial license[edit]

Now that Qt has a LGPL or even less restrictive license for most languages (as shown in the table Qt language bindings), why is there a commercial license and why would anybody need it? Does the product sold by Digia differ from the open source version?--Borishollas (talk) 18:49, 5 August 2012 (UTC)

Broken reference[edit]

Reference 70, LGPL License Option Added to Qt, is dead. The page is still alive, but the content is no longer at that location, if anywhere. (talk) 18:40, 17 September 2013 (UTC)

I replaced it with a link to "Nokia to license Qt under LGPL". Guy Harris (talk) 19:02, 17 September 2013 (UTC)

Users / Adopters[edit]

I created the Category:Software that uses Qt and Category:Software that uses GTK+ and populated them. It would be nice to know the version. What software uses Qt3, Qt4 or Qt5. AFAIK KDE Frameworks 5 and Plasma Next have been ported to Qt5 and the KDE Application will be in the future. Qt 5 was released on 19 December 2012, so I think it is lack of manpower that made KDE port so lately. What about Amarok and all the other software that uses Qt? What about proprietary software? User:ScotXWt@lk 17:13, 21 May 2014 (UTC)


I tried viewing those Pluralsight tutorials. Not only do they require sign-up to view, they have the audacity to ask for one's credit card details even to begin a free trial! Are we sure that such sites deserve to be linked to by Wikipedia? — Preceding unsigned comment added by Coylabe (talkcontribs) 16:25, 14 March 2015 (UTC)

External links modified[edit]

Hello fellow Wikipedians,

I have just added archive links to 2 external links on Qt (software). Please take a moment to review my edit. If necessary, add {{cbignore}} after the link to keep me from modifying it. Alternatively, you can add {{nobots|deny=InternetArchiveBot}} to keep me off the page altogether. I made the following changes:

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Cheers. —cyberbot IITalk to my owner:Online 11:25, 27 August 2015 (UTC)

For the Volvo link, I changed the URL in the url= parameter to include http:// - the documentation for Template:cite web shows it as taking a full URL, complete with the scheme. The Wayback Machine URL in the version before Cyberbot II's work was, which didn't include http:// before the original URL, which is probably why Cyberbot II didn't include it.
For the "Q... on Windows" link, I converted it to {{cite web}} and used a different archive URL - the one Cyberbot II picked didn't have any content; I guess the project removed the content when they abandoned the project (after Trolltech released the Windows Qt source). Guy Harris (talk) 19:01, 27 August 2015 (UTC)

External links modified[edit]

Hello fellow Wikipedians,

I have just added archive links to 8 external links on Qt (software). Please take a moment to review my edit. You may add {{cbignore}} after the link to keep me from modifying it, if I keep adding bad data, but formatting bugs should be reported instead. Alternatively, you can add {{nobots|deny=InternetArchiveBot}} to keep me off the page altogether, but should be used as a last resort. I made the following changes:

  • Attempted to fix sourcing for //
  • Attempted to fix sourcing for //
  • Attempted to fix sourcing for //
  • Attempted to fix sourcing for //
  • Attempted to fix sourcing for //
  • Attempted to fix sourcing for //
  • Attempted to fix sourcing for //
  • Attempted to fix sourcing for //

When you have finished reviewing my changes, please set the checked parameter below to true or failed to let others know (documentation at {{Sourcecheck}}).

YesY Archived sources have been checked to be working

Cheers.—cyberbot IITalk to my owner:Online 03:11, 31 March 2016 (UTC)