Making Qt available in CMake projects

Currently the only supported method of making Qt available for user projects is by having it pre-installed on the system, or any equivalent workflow that builds Qt ahead of time and makes it available to find_package, such as vcpkg.

When using Qt Creator or qt-cmake (qt-cmake.bat on Windows), the Qt installation location is automatically forwarded to the underlying CMake call.

When using cmake directly, the general search paths used by CMake should cover most non-user installations of Qt. For more control over which Qt package to use, you can pass https://cmake.org/cmake/help/latest/variable/PackageName_ROOT.html Qt6_ROOT as an environment or cache variable pointing to the Qt installation path, or by adding or appending to the CMAKE_PREFIX_PATH in a similar way. For example, if the installation path is "~/Qt/6.9.2/gcc_64", you would pass it on the command line as -DQt6_ROOT=$HOME/Qt/6.9.2/gcc_64.

cmake_minimum_required(VERSION 3.16)

project(helloworld)

find_package(Qt6 REQUIRED)

The Qt package is split into various modules that you need to include depending on the scope of your project, most basic of which is

find_package(Qt6 REQUIRED COMPONENTS Core)

Modern CMake supports other dependency providers such as FetchContent, however using Qt with FetchContent is not supported due to a tight integration of Qt features inside CMake itself. Adding Qt sources via add_subdirectory and Git submodules is not supported either.

Instead, repeatedly call find_package(Qt6) in all subdirectory scopes that use Qt functions, or move the find_package(Qt6) call to the root CMakeLists.txt.