How to add icon to cmake app in windows

cmake_windows_icon.txt

1. Put app.ico in directory.

2. Create app.rc in same directory with one line:
IDI_ICON1               ICON        DISCARDABLE            "app.ico"

3. Run command (Warning: it's app.o, not app.res, how it is mentioned in other manuals!)
windres app.rc -o app.o

4. add_executable(app
  ...
  app.o
)

5. Proofit!

Hi! I was using this method but actually discovered you can simply add the ".rc" file to the sources and it should just work...

how do i use the icon with multiple windows?

This post is incorrect. The Doc identify option /fo resname for anyone using cmake here is a snippet that generates the .RES script form RC compilation. Also make sure the resource.h file include windows.h header file .

adds a custom build step to a file. Generates the resources

add_custom_command(
TARGET LibTransactX
PRE_BUILD
DEPENDS RC
COMMAND RC /v /r ${CMAKE_SOURCE_DIR}/res/app.rc
WORKING_DIRECTORY "${CMAKE_SOURCE_DIR}/res"
COMMENT "Build step to produce the icon file"
)

Hi! I was using this method but actually discovered you can simply add the ".rc" file to the sources and it should just work...

Thank you for sharing, just including the .rc in sources allowed me to skip step 3 and 4.

ImGui GLFW window add icon

stbi_load function
https://github.com/nothings/stb/blob/master/stb_image.h

GLFWimage images[1];
images[0].pixels = stbi_load("icon_should_be_same_folder_with_exe.png", &images[0].width, &images[0].height, 0, 4);
glfwSetWindowIcon(window, 1, images);
stbi_image_free(images[0].pixels);

You can use magick to convert png to icon. The main thing is that the png sizes are the right size.
PNG dimensions: 16x16, 32x32, 256x256

In the console, we convert using magick:

magick.exe convert myIcon.png icon.ico

In CMakeLists.txt we specify the path to the rc file in add_executable, I had it like this:

add_executable(${PROJECT_NAME} WIN32
  ${ALL_HEADERS}
  ${ALL_SOURCES}
  qml.qrc
  resource/resource.qrc
  resource/app.rc
)

app.rc file:

IDI_ICON1 ICON DISCARDABLE "icon.ico"

this is easier
https://www.icoconverter.com/