How to add icon to a Qt application on Windows using a .rc file on a CMake project?

I'm trying to add an application icon to an application I'm writing, following what is described in https://doc.qt.io/qt-5/appicon.html

I'm using Qt Desktop 5.15.2 (64) and 6.1.2 (64) for both MinGW and MSVC, on Windows 10 64 bits. They all compile without error or warnings, but the icon doesn't show up.

My CMakeFile.txt:

cmake_minimum_required(VERSION 3.14)

project(MyApp VERSION 0.1 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 https://doc.qt.io/qt/deployment-android.html for more information.
# They need to be set before the find_package(...) calls below.

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(QT NAMES Qt6 Qt5 COMPONENTS Core Quick LinguistTools REQUIRED)
find_package(Qt${QT_VERSION_MAJOR} COMPONENTS Core Quick LinguistTools REQUIRED)

set(TS_FILES _pt_BR.ts)

set(PROJECT_SOURCES
        main.cpp
        qml.qrc
        ${TS_FILES}
)

if(${QT_VERSION_MAJOR} GREATER_EQUAL 6)
    set(APP_ICON_RESOURCE_WINDOWS "${CMAKE_CURRENT_SOURCE_DIR}/MyApp.rc")
    qt_add_executable(MyApp
        MANUAL_FINALIZATION
        ${PROJECT_SOURCES}
        ${APP_ICON_RESOURCE_WINDOWS}
    )

    qt_create_translation(QM_FILES ${CMAKE_SOURCE_DIR} ${TS_FILES})
else()
    if(ANDROID)
        add_library(MyApp SHARED
            ${PROJECT_SOURCES}
        )
    elseif(WIN32)
        set(APP_ICON_RESOURCE_WINDOWS "${CMAKE_CURRENT_SOURCE_DIR}/windows/MyApp.rc")
        add_executable(MyApp
            ${PROJECT_SOURCES}
            ${APP_ICON_RESOURCE_WINDOWS}
        )

    else()
        add_executable(MyApp
          ${PROJECT_SOURCES}
        )
    endif()

    qt5_create_translation(QM_FILES ${CMAKE_SOURCE_DIR} ${TS_FILES})
endif()

target_compile_definitions(MyApp
  PRIVATE $<$<OR:$<CONFIG:Debug>,$<CONFIG:RelWithDebInfo>>:QT_QML_DEBUG>)
target_link_libraries(MyApp
  PRIVATE Qt${QT_VERSION_MAJOR}::Core Qt${QT_VERSION_MAJOR}::Quick)

set_target_properties(MyApp PROPERTIES
    MACOSX_BUNDLE_GUI_IDENTIFIER my.example.com
    MACOSX_BUNDLE_BUNDLE_VERSION ${PROJECT_VERSION}
    MACOSX_BUNDLE_SHORT_VERSION_STRING ${PROJECT_VERSION_MAJOR}.${PROJECT_VERSION_MINOR}
)

if(QT_VERSION_MAJOR EQUAL 6)
    qt_import_qml_plugins(MyApp)
    qt_finalize_executable(MyApp)
endif()

MyApp.rc:

MyAppIcon ICON "MyApp.ico"

The .ico contains a single 256x256 32-bit RGBA image.

For what matters, after so many failures I tried creating a test project using qmake, and added the icon using RC_ICONS = QtTest.ico the .pro file, which worked (got the correct icon). When I tried using the RC_FILE = QtTest.rc instead it used the default icon, but without any warnings or errors.

Just in case I generated the .res file using windres, but to no avail. Changed QtTestIco ICON "QtTest.ico" and regenerated the .res, the same result.

Substituting the CMakeList.txt for a .pro file and using the RC_ICONS is not an option, sadly.

Somebody could help me, please?

Thanks in advance.

In order to add a Microsoft resources (RC) file, you need to tell CMake to support the "RC" language by enabling Microsoft's RC language. This will kick in the resource compiler when it detects a file with the *.rc extension in your project.

Here is a sample code snippet:

if (${CMAKE_SYSTEM_NAME} MATCHES "Windows")
    enable_language("RC")
    set (WIN32_RESOURCES ${CMAKE_CURRENT_SOURCE_DIR}/windows/MyApp.rc)
endif()

add_executable(MyApp WIN32
    ${PROJECT_SOURCES}
    ${WIN32_RESOURCES}
)

Build your project and Microsoft Explorer will then see your icon.