Windows

The Qt library has to be built with the same version of MSVC as Python and PySide, this can be selected when using the online installer.

Requirements

  • MSVC2022 for Python 3 on Windows,

  • OpenSSL (optional for SSL support, Qt must have been configured using the same SSL library).

  • sphinx package for the documentation (optional).

  • Check the platform dependencies of Qt for Windows.

Note

The Python provided by the Microsoft Store is not compatible with PySide. Please use https://www.python.org/downloads/ to get a Python Interpreter.

Building from source on Windows 10

Creating a virtual environment

The venv module allows you to create a local, user-writable copy of a python environment into which arbitrary modules can be installed and which can be removed after use:

python -m venv testenv
call testenv\Scripts\activate

will create and use a new virtual environment, which is indicated by the command prompt changing.

Alternatively, you can use the uv tool, which is popular in the Python community for Python project management. The following command creates a virtual environment using uv:

uv venv --python <python-version> testenv
call testenv\Scripts\activate

Note

Since the Qt for Python project still uses setup.py and not pyproject.toml, currently uv can only be used as a replacement for pyenv for building Qt for Python. If you have already the .python_version file (used by .pyenv) in the project, make sure to change the version to the uv Python you want to use.

Setting up CLANG

libclang can be downloaded from the Qt servers. for example, libclang-release_18.1.5-based-windows-vs2019_64.7z.

Note that from version 12 onwards, the prebuilt Windows binaries from LLVM no longer contain CMake configuration files; so they can no longer be used.

Extract the files, and leave it on any desired path, for example, c:, and set the environment variable required:

set LLVM_INSTALL_DIR=c:\libclang
set PATH=C:\libclang\bin;%PATH%

Getting PySide

Cloning the official repository can be done by:

git clone https://code.qt.io/pyside/pyside-setup

Checking out the version that we want to build, for example, 6.8:

cd pyside-setup && git checkout 6.8

Install the general dependencies:

pip install -r requirements.txt

For building the documentation:

pip install -r requirements-doc.txt

Note

Keep in mind you need to use the same version as your Qt installation

Note

With uv, use uv pip install …

Building PySide

Check your Qt installation path, to specifically use that version of qtpaths to build PySide. for example, C:\Qt\6.8.0\msvc2019_64\bin\qtpaths.exe.

Build can take a few minutes, so it is recommended to use more than one CPU core:

python setup.py build --qtpaths=c:\path\to\qtpaths.exe --openssl=c:\path\to\openssl\bin --build-tests --ignore-git --parallel=8

With uv, this command becomes:

uv run setup.py build --qtpaths=c:\path\to\qtpaths.exe --openssl=c:\path\to\openssl\bin --build-tests --ignore-git --parallel=8

Creating Debug Builds

  • Choose Custom Installation when installing Python and tick the options for debug binaries and libraries

  • Use venv to create a virtual environment and pass the debug binary:

    python_d.exe -m venv testenv_d

  • Use python_d.exe to invoke setup.py

Note

Make sure you add the --debug option to the python setup.py install to produce a debug build

Installing PySide

First, create the wheels using the `create_wheels.py`_ script:

python create_wheels.py --build-dir=C:\directory\where\pyside\is\built --no-examples

On successful completion, the wheels will be created in the dist directory.

Note

The build-dir typically looks like build<your_python_environment_name>. The requirement is that this build-dir should contain the packages_for_wheel directory. If the python setup.py build command was successful, this directory should be present.

Finally, to install the wheels, use the following command:

pip install dist\*.whl

Test installation

You can execute one of the examples to verify the process is properly working. Remember to properly set the environment variables for Qt and PySide:

python examples\widgets\widgets\tetrix\tetrix.py