Once I've built Qwt, how do I add it to a form in Designer?

[Joachie]

I built Qwt with VS.NET2008. How do I go about enabling Designer to see the dll so that I can add the chart widget to my forms?

Thx.

[bmhautz]

I'm actually having the same problem. I've built the Qwt designer dll using MinGW for Qt 4.5.0 and added the .dll and .a files to the plugin/designer directory. When I open Designer and look in the About:Plugins menu, I see the following error:

Cannot load library <Qt 4.5.0 path>/plugins/designer/qwt_designer_plugin5.dll: The specified module could not be found.

[bmhautz]

Okay, I've answered my own question (and hopefully the original submitter's as well). I needed to add the qwt dll itself to the /bin directory. Then everything was good.

(Be gentle, this is the first time I've installed external plugins to Qt. )

[Furr]

Okay, I've answered my own question (and hopefully the original submitter's as well). I needed to add the qwt dll itself to the /bin directory. Then everything was good.

Hi, I have the same problem as you... I would like to know which /bin directory are you talking about, because there are several /bin directory's same name and I don't know which one to choose...

Thanks a lot !

(I'm french, sorry if my english is not perfect... )

[Uwe]

On Windows DLLs are found using the PATH environment variable. On most UNIX systems the variable is called LD_LIBRARY_PATH ( or a path, that is configured by ld.so.conf ). This has nothing to do with any particular /bin directory beside it is obviously in the PATH of bmhautz.

I recommend to google for more informations about how shared libraries work, because this is a general concept each developer should have understood.

Uwe

[bmhautz]

On Windows DLLs are found using the PATH environment variable. On most UNIX systems the variable is called LD_LIBRARY_PATH ( or a path, that is configured by ld.so.conf ). This has nothing to do with any particular /bin directory beside it is obviously in the PATH of bmhautz.

I recommend to google for more informations about how shared libraries work, because this is a general concept each developer should have understood.

Uwe

It's not obvious at first that the qwt dll is needed for the plugins to work. The INSTALL file is very specific about compiling the libraries but trails off on how to actually get them working in Qt Designer/Qt Creator. Since several people other than myself are having difficulties with installing the plugins, maybe adding a few install steps to the INSTALL file wouldn't hurt?

Once I got everything working, I must say that QwtPlot is a very nice tool set indeed. Thanks for providing such a needed tool!

[derektaprell]

Hi guys,
I still can't solve this problem. qwt compiled ok. Installed ok. I even added a copy of qwt_designer_plugin5.dll to the qt/bin folder.

What else could be causing the error:

"Cannot load library C:/Qt/2009.01/qt/plugins/designer/qwt_designer_plugin5.dll: The specified module could not be found."

[brcain]

You need to make sure that you have the main Qwt bin directory in your path (or lib directory depending upon where the DLLs are). I created my own bin directory and copied the Qwt DLLs from the lib directory over because that's where I expect to see DLLs.

Anyways, since you already copied the Qwt plugin DLL to the designer plugins directory, the problem is likely NOT that it can't find the Qwt plugin ... but rather that it can't find the main Qwt DLL.