问题
I've installed QWT 6.1.0 over a Qt 5.0.1. It installed correctly, but I have one problem with QWT Designer plugin: when I accessing QtDesigner separatly it works correct. But when I trying to use it inside a Creator it don't works: there is no qwt widgets in a form, althogh it builds correctly and widgets are displaying on a runtime.
Next system variables are set: QT_PLUGIN_PATH = C:\Qwt-6.1.0\plugins QMAKEFEATURES = C:\Qwt-6.1.0\features
In "Tools->Form Editor->QtDesigner Plugins" it is written that creator can't find necessary [rocedure
回答1:
The reason might be on the compatibility of your QTCreator with the the ACTUAL QT framework you built QWT against.
The "Qt 5.1.1 for Windows 64-bit (VS 2012, OpenGL, 522 MB)" package provided in QT-Project.org/Download has the QT libraries built against MSVCR110 (C++ 2012) 64 bits where as the actual QTCreator.exe is built against MSCVR100 (C++ 2010). That's why the QWT plugin load successfully form the stand-alone QT Designer that comes in the QT framework, but not on the QT creator that comes in the Tools/ directory. To check this, load the QTCreator executable in Dependency Walker and you'll see.
My recommendation is that you download the source code of QT, build it with your compiler and then compile the QWT using the same compiler. A bit tedious but at least you'll be sure that your plugins will load.
来源：https://stackoverflow.com/questions/17946192/qwt-designer-plugin-is-inaccesable-via-qtcreator-built-in-designer