CMake:OSX InterfaceBuilderFiles

How to use OS X Interface Builder .xib files in your project

Using Apple's Developer tools usually programmers will use Interface Builder to create their user interfaces. These files are stored in a newer XML file format with the extension .xib. These files need to be "compiled" using the 'ibtool' into the older style .nib files and placed into the application bundle. The following is the CMake code from the VTK/Examples/GUI/Cocoa project where this is performed.

#--////////////////////////////////////////////////////////////////////////////
#--  Copyright (c) 2010, Michael A. Jackson. BlueQuartz Software
#--  All rights reserved.
#--  BSD License: http://www.opensource.org/licenses/bsd-license.html
#--////////////////////////////////////////////////////////////////////////////
project(SimpleCocoaVTK)
CMAKE_MINIMUM_REQUIRED(VERSION 2.6.3 FATAL_ERROR)

if(NOT VTK_BINARY_DIR)
  find_package(VTK)
  if(NOT VTK_DIR)
    message(FATAL_ERROR "Please set VTK_DIR.")
  endif(NOT VTK_DIR)
  include(${VTK_USE_FILE})
endif(NOT VTK_BINARY_DIR)

# This is needed in case we are building this project separate from the VTK build
if (NOT EXECUTABLE_OUTPUT_PATH)
  set (EXECUTABLE_OUTPUT_PATH ${SimpleCocoaVTK_BINARY_DIR})
endif()

# The source files - Note because the files have both C++ and Objective-C in them
# the file extension is .mm
set (SimpleCocoaVTK_SRCS
  ${SimpleCocoaVTK_SOURCE_DIR}/main.mm
  ${SimpleCocoaVTK_SOURCE_DIR}/BasicVTKView.mm 
  ${SimpleCocoaVTK_SOURCE_DIR}/MyDocument.mm
)

# The Headers
set (SimpleCocoaVTK_HDRS
  ${SimpleCocoaVTK_SOURCE_DIR}/BasicVTKView.h
  ${SimpleCocoaVTK_SOURCE_DIR}/MyDocument.h
)

# these are the OS X Interface Builder Files
set (SimpleCocoaVTK_XIBS
  MainMenu
  MyDocument
)

# Set the OS X Bundle specific CMake variables which will be used to populate the plist for
# the application bundle
set(MACOSX_BUNDLE_INFO_STRING "${PROJECT_NAME}")
set(MACOSX_BUNDLE_GUI_IDENTIFIER "com.rogue-research.SimpleCocoaVTK")
set(MACOSX_BUNDLE_LONG_VERSION_STRING "${PROJECT_NAME} Version ${VTK_VERSION}")
set(MACOSX_BUNDLE_BUNDLE_NAME ${PROJECT_NAME})
set(MACOSX_BUNDLE_SHORT_VERSION_STRING ${VTK_VERSION})
set(MACOSX_BUNDLE_BUNDLE_VERSION ${VTK_VERSION})
set(MACOSX_BUNDLE_COPYRIGHT "Copyright 2010. All Rights Reserved.")

# These variables are specific to our plist and are NOT standard CMake variables
set(MACOSX_BUNDLE_NSMAIN_NIB_FILE "MainMenu")
set(MACOSX_BUNDLE_NSPRINCIPAL_CLASS "NSApplication")

# Add our Executable
add_executable(SimpleCocoaVTK MACOSX_BUNDLE ${SimpleCocoaVTK_SRCS} ${SimpleCocoaVTK_HDRS})

# Probably a better way to set the framework link libraries.
target_link_libraries(SimpleCocoaVTK vtkRendering "-framework Cocoa -framework OpenGL -framework IOKit")

# Set a custom plist file for the app bundle
set_target_properties(SimpleCocoaVTK PROPERTIES MACOSX_BUNDLE_INFO_PLIST ${SimpleCocoaVTK_SOURCE_DIR}/Info.plist)

# Make sure we can find the 'ibtool' program. If we can NOT find it we
# skip generation of this project
find_program(IBTOOL ibtool HINTS "/usr/bin" "${OSX_DEVELOPER_ROOT}/usr/bin")
if (${IBTOOL} STREQUAL "IBTOOL-NOTFOUND")
  message(SEND_ERROR "ibtool can not be found and is needed to compile the .xib files. It should have been installed with 
                    the Apple developer tools. The default system paths were searched in addition to ${OSX_DEVELOPER_ROOT}/usr/bin")
endif()

# Make sure the 'Resources' Directory is correctly created before we build
add_custom_command (TARGET SimpleCocoaVTK PRE_BUILD
                      COMMAND mkdir -p ${EXECUTABLE_OUTPUT_PATH}/\${CONFIGURATION}/SimpleCocoaVTK.app/Contents/Resources)

# Compile the .xib files using the 'ibtool' program with the destination being the app package
foreach(xib ${SimpleCocoaVTK_XIBS})
  add_custom_command (TARGET SimpleCocoaVTK POST_BUILD 
                      COMMAND ${IBTOOL} --errors --warnings --notices --output-format human-readable-text 
                              --compile ${EXECUTABLE_OUTPUT_PATH}/\${CONFIGURATION}/SimpleCocoaVTK.app/Contents/Resources/${xib}.nib 
                             ${SimpleCocoaVTK_SOURCE_DIR}/${xib}.xib
                      COMMENT "Compiling ${SimpleCocoaVTK_SOURCE_DIR}/${xib}.xib")

endforeach()