Can't even start ("Qt Designer Plugins (Part 5)" given example "QtDesignerPlugin-part2") trying this due to line 62, "include(QtInstallPaths)"

Qt_Student

So, what log files or whatever can I give somebody to tell me what setting is set wrong, or what is wrong?

So, I have been following this series,
Qt Designer Plugins posted by KDAB to learn how to create plugins.
https://www.youtube.com/playlist?list=PL6CJYn40gN6iNg0nIYH4QLhYkfs5PslbA

I've been able to compile in Qt Creator each one of these projects for each of the videos. This is the only one that won't work, and I'm not sure what to do about it.

So far, I've only had to make sure things say Qt6 instead of 5, and set the cmake_minimum_required version correctly.

My setup is Qt 6.11.1 installed from source using the configure.bat --release-and-debug=yes option. I am using Windows 11 and Qt Creator 20.0.1. I have Visual Studio 2026 installed, but I had to use 2022's development tools by setting the vcvarsall.bat's option
-vcvars_ver=14.44. I don't know if that's an issue or not.

My issue keeps hitting on line 62 of the CMakeLists.txt file included with part 2 of this, which is video 5 in the series.

This line 62 has the instruction:
include(QtInstallPaths)

The part 1 of this, 4th video in the series, did not have this instruction.

I cannot even build the project at the moment because Qt Creator has not setup the project correctly yet due to that issue on line 62. Right now, it's just a list of the files without any distribution of the files to the appropriate sections of the project.

The error provided is:
C:\path\to\project\directory\QtDesignerPlugin-part2\CMakeLists.txt:62: error: No supported Qt version found. Make sure you find Qt before calling this

Call stack:
CMakeLists.txt:62 (include)
cmake/QtInstallPaths.cmake:42 (message)
:-1: error: The command "D:\path\to\cmake\cmake421\bin\cmake.exe -S C:/path/to/project/directory/QtDesignerPlugin-part2 -B C:/path/to/project/directory/QtDesignerPlugin-part2/build/x86_windows_msvc2026_pe_64bit_RelWithDebInfo" terminated with exit code 1.
:-1: error: CMake project configuration failed. No CMake configuration for build type "RelWithDebInfo" found. Check General Messages for more information.

I am hoping this is a common problem, since I have done nothing to this example project other than change the Qt5 to Qt6 and the minimum cmake version to 3.16 from 3.3. 3.3 was giving me an error until I changed it.

Thank you.

Nils Sjoberg

# --- מציאת Qt6 לפני include(QtInstallPaths) ---
find_package(QT NAMES Qt6 REQUIRED)
find_package(Qt${QT_VERSION_MAJOR} REQUIRED COMPONENTS
    Core
    Widgets
    UiPlugin      # נדרש לתוספי Designer — הסר אם לא רלוונטי
    Designer      # נדרש לתוספי Designer — הסר אם לא רלוונטי
)