Can't link MacOS frameworks with CMake

Question

I'm trying to build a subproject with cmake (it's not an xcode project or even an app for iphone, the result is cross-platform console executable, which #includes some inherited from C++ abstract classes, written in objective-c++)

I'm using this guide to link mac os frameworks: http://www.vtk.org/Wiki/CMake:HowToUseExistingOSXFrameworks

and this macro:

macro(ADD_FRAMEWORK fwname appname)
find_library(FRAMEWORK_${fwname}
    NAMES ${fwname}
    PATHS ${CMAKE_OSX_SYSROOT}/System/Library
    PATH_SUFFIXES Frameworks
    NO_DEFAULT_PATH)
if( ${FRAMEWORK_${fwname}} STREQUAL FRAMEWORK_${fwname}-NOTFOUND)
    MESSAGE(ERROR ": Framework ${fwname} not found")
else()
    TARGET_LINK_LIBRARIES(${appname} ${FRAMEWORK_${fwname}})
    MESSAGE(STATUS "Framework ${fwname} found at ${FRAMEWORK_${fwname}}")
endif()
endmacro(ADD_FRAMEWORK)

This is the important part in CMakeLists.txt

project(myprojectname)
........
add_executable(mytarget src/mytarget.cpp)

add_framework(CoreMedia mytarget)
add_framework(CoreVideo mytarget)
add_framework(AVFoundation mytarget)
add_framework(Foundation mytarget)
........

And that's what i have when trying to build:

WARNING: Target "mytarget" requests linking to directory "/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS6.0.sdk/System/Library/Frameworks/CoreMedia.framework".  Targets may link only to libraries.  CMake is dropping the item.
WARNING: Target "mytarget" requests linking to directory "/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS6.0.sdk/System/Library/Frameworks/CoreVideo.framework".  Targets may link only to libraries.  CMake is dropping the item.
WARNING: Target "mytarget" requests linking to directory "/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS6.0.sdk/System/Library/Frameworks/AVFoundation.framework".  Targets may link only to libraries.  CMake is dropping the item.
WARNING: Target "mytarget" requests linking to directory "/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS6.0.sdk/System/Library/Frameworks/Foundation.framework".  Targets may link only to libraries.  CMake is dropping the item.

It actually finds all these frameworks, but can't link, which produces a lot of linker errors. I'm pretty sure that that's the reason because i made a testproj using XCode and it has the same errors till i linked all the needed frameworks.

When i just use

FIND_LIBRARY(COREMEDIA_LIB CoreMedia)
...

then COREMEDIA_LIB is set to NOTFOUND - what's going on? :/

I googled a lot but nothing :( Feeling pretty much lost there.

Answer 1

Got the thing: you have to link NOT the frameworkname.framework folder in the TARGET_LINK_LIBRARIES, but the fwname.framework/fwname file! Now it works that way.

The changed macro is this:

macro(ADD_FRAMEWORK fwname appname)
    find_library(FRAMEWORK_${fwname}
    NAMES ${fwname}
    PATHS ${CMAKE_OSX_SYSROOT}/System/Library
    PATH_SUFFIXES Frameworks
    NO_DEFAULT_PATH)
    if( ${FRAMEWORK_${fwname}} STREQUAL FRAMEWORK_${fwname}-NOTFOUND)
        MESSAGE(ERROR ": Framework ${fwname} not found")
    else()
        TARGET_LINK_LIBRARIES(${appname} "${FRAMEWORK_${fwname}}/${fwname}")
        MESSAGE(STATUS "Framework ${fwname} found at ${FRAMEWORK_${fwname}}")
    endif()
endmacro(ADD_FRAMEWORK)

Hope it will be useful for someone...