Using CMake build system

[tomy]

Hi all,

Have you used CMake instead of qmake in your Qt Widgets projects, please?
For me, it's the first time and want to make use of Docs (https://doc.qt.io/qt-5/cmake-get-started.html) for that, but it's ambiguous as usual (mostly).
I did these:
Created a Qt project called CMTest inheriting QLabel as the base class and without a .ui file and selecting CMake as the build system.
It now looks like this:

Then Docs say:

For find_package to be successful, CMake must find the Qt installation in one of the following ways:
Set your CMAKE_PREFIX_PATH environment variable to the Qt 5 installation prefix. This is the recommended way.

But I can't find CMAKE_PREFIX_PATH environment variable in the Projects > Build Environment list (Details)!

[jsulm]

@tomy said in Using CMake build system:

But I can't find CMAKE_PREFIX_PATH environment variable in the Projects > Build Environment list (Details)!

You can always add variables there...

[tomy]

@jsulm

I did that this way, if it's correct:

And this is my CMake text file contents:

cmake_minimum_required(VERSION 3.5)

project(CMTest LANGUAGES CXX)

set(CMAKE_INCLUDE_CURRENT_DIR ON)

set(CMAKE_AUTOUIC ON)
set(CMAKE_AUTOMOC ON)
set(CMAKE_AUTORCC ON)

set(CMAKE_CXX_STANDARD 11)
set(CMAKE_CXX_STANDARD_REQUIRED ON)

# QtCreator supports the following variables for Android, which are identical to qmake Android variables.
# Check http://doc.qt.io/qt-5/deployment-android.html for more information.
# They need to be set before the find_package(Qt5 ...) call.

#if(ANDROID)
#    set(ANDROID_PACKAGE_SOURCE_DIR "${CMAKE_CURRENT_SOURCE_DIR}/android")
#    if (ANDROID_ABI STREQUAL "armeabi-v7a")
#        set(ANDROID_EXTRA_LIBS
#            ${CMAKE_CURRENT_SOURCE_DIR}/path/to/libcrypto.so
#            ${CMAKE_CURRENT_SOURCE_DIR}/path/to/libssl.so)
#    endif()
#endif()

find_package(Qt5 COMPONENTS Widgets REQUIRED)

if(ANDROID)
  add_library(CMTest SHARED
    main.cpp
    cmtest.cpp
    cmtest.h
  )
else()
  add_executable(CMTest
    main.cpp
    cmtest.cpp
    cmtest.h
  )
endif()

target_link_libraries(CMTest PRIVATE Qt5::Widgets)

When I run CMake, these error emerge:

I'm confused and don't know what to do next! :(

[jsulm]

@tomy You set wrong path. Take a look at https://stackoverflow.com/questions/22215900/add-the-installation-prefix-of-qt5widgets-to-cmake-prefix-path
Also, as you can see Ninja was not found. If you do not have it then set Make as build tool.

[tomy]

@jsulm

I've Ninja at: "C:\Qt\Tools\Ninja"
So added the following two lines

set(CMAKE_PREFIX_PATH "C:\\Qt\\5.14.2\\mingw73_64\\bin\\")
set(CMAKE_MAKE_PROGRAM "C:\\Qt\\Tools\\Ninja\\")

after:

cmake_minimum_required(VERSION 3.5)
project(CMTest LANGUAGES CXX)

in CMakeLists.txt file

As well as, changed the CMAKE_PREFIX_PATH on Build Environment to C:\Qt\5.14.2\mingw73_64\bin.

Still the same errors! Why are the stuff that complicated?! :(

[jsulm]

@tomy said in Using CMake build system:

CMAKE_MAKE_PROGRAM

This needs to point to the executable, not a directory! So, whole path to ninja.exe.

"set(CMAKE_PREFIX_PATH "C:\Qt\5.14.2\mingw73_64\bin\")" - this needs to be

set(CMAKE_PREFIX_PATH "C:\\Qt\\5.14.2\\mingw73_64")

[tomy]

@jsulm

Did these both:

set(CMAKE_PREFIX_PATH "C:\\Qt\\5.14.2\\mingw73_64")
set(CMAKE_MAKE_PROGRAM "C:\\Qt\\Tools\\Ninja\\ninja.exe")

And:

Still both prior errors exist!

This is my CMakeLists.txt file contents:

cmake_minimum_required(VERSION 3.5)

project(CMTest LANGUAGES CXX)

set(CMAKE_PREFIX_PATH "C:\\Qt\\5.14.2\\mingw73_64")
set(CMAKE_MAKE_PROGRAM "C:\\Qt\\Tools\\Ninja\\ninja.exe")


set(CMAKE_INCLUDE_CURRENT_DIR ON)

set(CMAKE_AUTOUIC ON)
set(CMAKE_AUTOMOC ON)
set(CMAKE_AUTORCC ON)

set(CMAKE_CXX_STANDARD 11)
set(CMAKE_CXX_STANDARD_REQUIRED ON)

# QtCreator supports the following variables for Android, which are identical to qmake Android variables.
# Check http://doc.qt.io/qt-5/deployment-android.html for more information.
# They need to be set before the find_package(Qt5 ...) call.

#if(ANDROID)
#    set(ANDROID_PACKAGE_SOURCE_DIR "${CMAKE_CURRENT_SOURCE_DIR}/android")
#    if (ANDROID_ABI STREQUAL "armeabi-v7a")
#        set(ANDROID_EXTRA_LIBS
#            ${CMAKE_CURRENT_SOURCE_DIR}/path/to/libcrypto.so
#            ${CMAKE_CURRENT_SOURCE_DIR}/path/to/libssl.so)
#    endif()
#endif()

find_package(Qt5 COMPONENTS Widgets REQUIRED)

if(ANDROID)
  add_library(CMTest SHARED
    main.cpp
    cmtest.cpp
    cmtest.h
  )
else()
  add_executable(CMTest
    main.cpp
    cmtest.cpp
    cmtest.h
  )
endif()

target_link_libraries(CMTest PRIVATE Qt5::Widgets)