[CMake] Automatically pull in dependencies from QtDesigner plugins

[Michael Jackson]

On Dec 5, 2011, at 8:29 AM, David Doria wrote:

> On Sun, Dec 4, 2011 at 11:34 AM, Michael Jackson
> <mike.jackson at bluequartz.net> wrote:
>> Do you have "MyWidget" packaged as a true library, or did you just create the Designer Plugin and then have a "loose" .cpp/.h file?
>> 
>>  The is a project called Qwt* that has a similar setup. It has a Designer plugin for its various widgets and it has a qwt.dylib/.dll/.so that your program links against. You might be able to use this type of workflow for your project. In rough form this is what I am suggesting:
>> 
>> Create a MyWidget project that builds the Designer plugin and a dynamic library. When the project "installs" it will install its headers and library under its own install location and also install the Designer plugin into the appropriate location inside the Qt distribution you are using. The MyWidget would also include the necessary CMake EXPORT files or what ever so other projects can use it.
>> 
>> In the project that actually _uses_ MyWidget, you call "find_package(MyWidget)" which will setup all the necessary include directories and "MyWidget_LIBRARIES" variables.
>> 
>> *Normal Qwt at Sourceforge does NOT use CMake as a build system. I have created a CMake build system for Qwt which is located on my public git-web server.
>> 
>> Hope some of that helps.
> 
> Thanks Mike,
> 
> I tried simply placing the Widget in a subdirectory called Widget. I
> got it to work, but I am confused about one thing. If in the main
> project CMakeLists.txt I add:
> add_subdirectory(Widget)
> 
> and then in Widget/CMakeLists.txt I add:
> 
> include_directories(${CMAKE_CURRENT_SOURCE_DIR} ${CMAKE_CURRENT_BINARY_DIR})
> 
> I get errors that LabeledSlider.h can't find ui_LabeledSlider.h, and
> main.cpp can't find LabeledSlider.h (problems with uic). However, if
> instead I add directly to the main project CMakeLists.txt:
> 
> include_directories(${CMAKE_CURRENT_BINARY_DIR}/Widget)
> include_directories(${CMAKE_CURRENT_SOURCE_DIR}/Widget)
> 
> it works fine. Can you explain the difference between these two
> methods of adding the include directories? I have setup both cases
> here: http://daviddoria.com/Uploads/QtSubdirectory.tar.gz
> 
> Thanks,
> 
> David

Basically you have to figure out where "ui_LabeledSlider.h" is being generated and make sure that directory is being added via "include_directories". Once you work through that the other errors may go away.

----
Mike Jackson