[Qt-interest] QT plugins, dynamic and static version

[Patric]

I see... Thank you very much for your answer, Berry,
But where I can configure QT to be build either statically or dynamically ? 
And what do you mean by "symbols" ?

----- Original Message ----- 
From: "Berry Octave" <octave at octavious.servegame.org>
To: <qt-interest at trolltech.com>
Sent: Friday, May 29, 2009 5:19 PM
Subject: Re: [Qt-interest] QT plugins, dynamic and static version


> Le Friday 29 May 2009 12:41:11 Parker, vous avez écrit :
>> Hello all,
>> I have an application with tabs, and I want these tabs to be generated
>> dynamically, i.e. when you click a button, there will be new tab 
>> appearing,
>> some other is changing, etc. So, I need to define each tab as separate
>> class and load it dynamically. But what to use ? I want when the
>> application is installed, if there is the need of adding additional
>> functionalities, just to place one file in the program's folder and then
>> the new functionality (tab for instance) to be loaded. Or something like
>> that. I think I'll be able to do it with dynamic libraries, or QT plugins
>> maybe ? I'm not sure what's the difference, maybe it can be done with the
>> lower-level api of qt plugins OR with dynamic lybraries.
>>
>> Also, it is said that there are two versions of QT, dynamic and static ?
>> What do this means, where I can read about it ?
>>
>> I'm using WIndows XP.
>>
>> Regards,
>> Patric
>>
>>
>> __________ Information from ESET NOD32 Antivirus, version of virus
>> signature database 4098 (20090522) __________
>>
>> The message was checked by ESET NOD32 Antivirus.
>>
>> http://www.eset.com
>
>
> Hi,
>
> In fact, there are few differences between a dynamic library and a Qt 
> plugin.
>
> A library is used to be a set of functions that a program is allowed to 
> use.
> The difference between a static and a dynamic library is quite simple. 
> With a
> static library, the whole library code is included in the executable at 
> link
> time. Wherhas, on a dll, the code is resolved at runtime (by the linker or 
> by
> the program itself).
>
> Qt can be built as a static and as a dynamic library. In fact, with a 
> simple
> recompilation, the programs can use both kind of libraries (beacause it's 
> the
> linker's job to do that, at compile time (for static libs) or at the 
> program
> startup).
>
> The last case is when a program load itself a dll. I mean it has to 
> resolve
> the symbols by itself. (see man dlopen for the unix implementation as an
> example).
>
> But symbols are for example a function, not a whole class.
>
> In order to use a dll using this way in a C++ program, you have to make 
> some
> more gymnastic, that the Qt plugins abstraction does for you.
>
> To answer to your question, for the use you want to do, you should use Qt
> plugins.
>
> Have a look at
> http://doc.qtsoftware.com/4.5/tools-plugandpaintplugins-basictools.html 
> for
> an exemple implementation.
>
>
> _______________________________________________
> Qt-interest mailing list
> Qt-interest at trolltech.com
> http://lists.trolltech.com/mailman/listinfo/qt-interest
>