[CMake] FindQt4.cmake to automatically include QT_USE_FILE?

[Rolf Eike Beer]

> Hi all,
>
> As far as I can tell, all Qt programs built with CMake must include
> QT_USE_FILE after find_package(). So why doesn't FindQt4.cmake simply
> include QT_USE_FILE itself? Is there maybe a use case where
> QT_USE_FILE is *not* wanted?

Besides the points already given here is another example:

CMakeLists.txt:

find_package(Qt4 REQUIRED)
add_subdirectory(a)
add_subdirectory(b)

a/CMakeLists.txt

SET(QT_DONT_USE_QTGUI TRUE)
INCLUDE(${QT_USE_FILE})
...
TARGET_LINK_LIBRARIES(foo ${QT_LIBRARIES})

b/CMakeLists.txt
INCLUDE(${QT_USE_FILE})
...
TARGET_LINK_LIBRARIES(bar ${QT_LIBRARIES})

So bar would get linked against QtGui, but foo not. And this all without
fiddling with all the single Qt libraries and their dependencies.

Eike