Most simple but complete CMake example

Question

Somehow I am totally confused by how CMake works. Every time I think that I am getting closer to understand how CMake is meant to be written, it vanishes in the next example I r

Answer 1

The most basic but complete example can be found in the CMake tutorial :

cmake_minimum_required (VERSION 2.6)
project (Tutorial)
add_executable(Tutorial tutorial.cxx)

For your project example you may have:

cmake_minimum_required (VERSION 2.6)
project (MyProject)
add_executable(myexec src/module1/module1.cpp src/module2/module2.cpp src/main.cpp)
add_executable(mytest test1.cpp)

For your additional question, one way to go is again in the tutorial: create a configurable header file that you include in your code. For this, make a file configuration.h.in with the following contents:

#define RESOURCES_PATH "@RESOURCES_PATH@"

Then in your CMakeLists.txt add:

set(RESOURCES_PATH "${PROJECT_SOURCE_DIR}/resources/"
# configure a header file to pass some of the CMake settings
# to the source code
configure_file (
  "${PROJECT_SOURCE_DIR}/configuration.h.in"
  "${PROJECT_BINARY_DIR}/configuration.h"
)

# add the binary tree to the search path for include files
# so that we will find TutorialConfig.h
include_directories("${PROJECT_BINARY_DIR}")

Finally, where you need the path in your code, you can do:

#include "configuration.h"

...

string resourcePath = string(RESOURCE_PATH) + "file.png";