I've read through the tutorials of Qt, I've searched the net, but I can't find the exact way on how to build custom witgets with Qt 5.8.x. In example with this tutorial one is able to build widgets for Qt 4.x as I already succeeded. For Qt 5.8.x I'am lacking in such straightforward tutorials.
Even if you use the build in wizard of Qt for setting up such custom widgets projects, one will end up with none recognized widget libraries.
So first of all, there is a confusion with the installing path, that the makefile should mention while installing the plugin.
In the project file one can find the section
target.path = $$[QT_INSTALL_PLUGINS]/designer
INSTALLS += target
After a straightforward installation of the open source mingw version of Qt 5.8.0 on a windows 7 machine in the path C:\Qt\Qt5.8.0, the variable "QT_INSTALL_PLUGINS" will extend to
C:\Qt\Qt5.8.0\5.8\mingw53_32\plugins
thus the "target.path" for the
make install
will be read as
C:\Qt\Qt5.8.0\5.8\mingw53_32\plugins\designer
But on the plain installation of Qt 5.8.0 with mingw the designer searches its plugins in
C:\Qt\Qt5.8.0\Tools\QtCreator\bin\plugins\designer\
As someone already suggested to me, one has to set the environment variable "QT_PLUGIN_PATH", where Qt Creator as well as Qt Designer ( in the subdirector "designer") searches its plugins in. So in order that Qt Creator still works properly one has to set the environment variable "QT_PLUGIN_PATH" to
- the original path as well as to
- the install path reffered to by $$[QT_INSTALL_PLUGINS]
So on my Windows 7 environment I set the variable "QT_PLUGIN_PATH" to
C:\Qt\Qt5.8.0\Tools\QtCreator\bin\plugins;C:\Qt\Qt5.8.0\5.8\mingw53_32\plugins
Afterwards Qt Designer is able to find the custom build widget library. But Qt Designer it not able to load the library. One interesting thing is that the designer also refuses the libraries provided by the installation of Qt itself.
- on loading the custom widget lib it says:
"... .dll can't be loaded: the given procedure was not found"
- on loading the libs supplied by the Qt distribution itselfs in the path C:\Qt\Qt5.8.0\5.8\mingw53_32\plugins\designer it says:
"... .dll cant be loaded: the mentioned modul was not found"
What I've done to build the library is, that I just ran through the project wizard to generate a custom widget for Qt Designer. With the so generated project I get the result of a non loadable lib, as mentioned above.
What do I have to change in the source/project files in order that the Qt Designer ist able to load the lib properly?
Thanks for any hints or suggestions!
