Qt For Python

Qt For Python is the Python Qt bindings project, providing access to the complete Qt framework as well as to generator tools for rapidly generating bindings for any C++ libraries.

Shiboken is the generator used to build the bindings.

See README.pyside6.md and README.shiboken6.md for details.

Building

To build both Shiboken and PySide simply execute:

• python setup.py build, or
• python setup.py install

to build and install into your current Python installation.

The same setup.py script is used to build all the components of the project:

• shiboken6 (the supporting Python module)
• shiboken6-generator (the bindings generation executable)
• PySide6

Preferably, a Qt (build) environment should be used to automatically pick up the associated qtpaths6, but optionally one can specify the location of qtpaths6 and cmake if it is not in the current PATH with:

• --qtpaths=/path/to/qt/bin/qtpaths6, and
• --cmake=/path/to/bin/cmake

respectively.

By default, all of the above is built when no special options are passed to the script. You can use the --build-type parameter to specify which things should be built:

• --build-type=shiboken6, build/package only the python module
• --build-type=shiboken6-generator, build/package the generator executable
• --build-type=pyside6, build/package the PySide6 bindings.
• --build-type=all, the implicit default to build all of the above

When building PySide6, optionally, one can specify the location of the shiboken6 cmake config path if it is not on the current PATH with:

• --shiboken-config-dir=/path/to/shiboken/cmake/config/dir

This is useful if you did a cmake installation of shiboken6 into a custom location.

For Windows, if OpenSSL support is required, it's necessary to specify the directory path that contains the OpenSSL shared libraries libeay32.dll and ssleay32.dll, for example:

• --openssl=C:\OpenSSL-Win64\bin

This will make sure that the libraries are copied into the PySide6 package and are found by the QtNetwork module.

Building Additional Options

On Linux and macOS you can use the option --standalone to embed Qt libraries into the PySide6 package. The option does not affect Windows, because it is used implicitly, i.e. all relevant DLLs have to be copied into the PySide6 package anyway, because there is no proper rpath support on the platform.

You can use the option --rpath=/path/to/lib/path to specify which rpath values should be embedded into the PySide6 modules and shared libraries. This overrides the automatically generated values when the option is not specified.

You can use the option --qt-conf-prefix to pass a path relative to the PySide6 installed package, which will be embedded into an auto-generated qt.conf registered in the Qt resource system. This path will serve as the PrefixPath for QLibraryInfo, thus allowing to choose where Qt plugins should be loaded from. This option overrides the usual prefix chosen by --standalone option, or when building on Windows.

To temporarily disable registration of the internal qt.conf file, a new environment variable called PYSIDE_DISABLE_INTERNAL_QT_CONF is introduced.

You should assign the integer "1" to disable the internal qt.conf, or "0" (or leave empty) to keep using the internal qt.conf file.

Development Options

For development purposes the following options might be of use, when using setup.py build:

• --ignore-git, will skip the fetching and checkout steps for supermodule and all submodules.
• --limited-api=yes|no, default yes if applicable. Set or clear the limited API flag. Ignored for Python 2.
• --module-subset, allows for specifying the Qt modules to be built. A minimal set is: --module-subset=Core,Gui,Test,Widgets.
• --package-timestamp, allows specifying the timestamp that will be used as part of the version number for a snapshot package. For example given --package-timestamp=1529646276 the package version will be 5.x.y.dev1529646276.
• --reuse-build, option allows recompiling only the modified sources and not the whole world, shortening development iteration time.
• --sanitize-address, will build the project with address sanitizer.
• --skip-cmake, will reuse the already generated Makefiles (or equivalents), instead of invoking, CMake to update the Makefiles (note, CMake should be ran at least once to generate the files).
• --skip-docs, skip the documentation generation.
• --skip-make-install, will not run make install (or equivalent) for each module built.
• --skip-modules, allows for specifying the Qt modules that will be skipped during the build process. For example: --skip-modules=WebEngineCore,WebEngineWidgets
• --skip-packaging, will skip creation of the python package, enabled (Linux or macOS only).
• --verbose-build, will output the compiler invocation with command line arguments, etc.

Requirements

• Python 3.7+ is supported,
• CMake: Specify the path to cmake with --cmake option or add cmake to the system path.
• Qt 6.2+ is supported. Specify the path to qtpaths with --qtpaths option or add qtpaths6 to the system path.

Optional

OpenSSL:

Specifying the --openssl option only affects Windows. It is a no-op for other platforms.

Please note that official Windows packages do not ship the OpenSSL libraries due to import/export restrictions as described in https://doc.qt.io/qt-6/ssl.html#import-and-export-restrictions

You can specify the location of the OpenSSL DLLs with the following option: --openssl=</path/to/openssl/bin-directory>.

You can download OpenSSL for Windows here

Official Qt packages do not link to the SSL library directly, but rather try to find the library at runtime.

On Windows, official Qt builds will try to pick up OpenSSL libraries at application path, system registry, or in the PATH environment variable.

On macOS, official Qt builds use SecureTransport (provided by OS) instead of OpenSSL.

On Linux, official Qt builds will try to pick up the system OpenSSL library.

Note: this means that Qt packages that directly link to the OpenSSL shared libraries, are not currently compatible with standalone PySide6 packages.

macOS SDK:

You can specify which macOS SDK should be used for compilation with the option --macos-sysroot=</path/to/sdk>, for example:

--macos-sysroot=/Applications/Xcode.app/.../Developer/SDKs/MacOSX10.12.sdk/

macOS minimum deployment target:

You can specify a custom macOS minimum deployment target with the option --macos-deployment-target=<value>, for example:

--macos-deployment-target=10.10

If the option is not set, the minimum deployment target of the used Qt library will be used instead. Thus it is not necessary to use the option without a good reason.

If a new value is specified, it has to be higher or equal to both Python's and Qt's minimum deployment targets.

Description: macOS allows specifying a minimum OS version on which a binary will be able to run. This implies that an application can be built on a machine with the latest macOS version installed, with latest Xcode version and SDK version and the built application can still run on an older OS version.

CMake super project

For development convenience, a CMake super project is included in the root of the repository.

The super project can be built using standalone CMake, or using an IDE's CMake integration (Qt Creator for example).

Nevertheless the default build process is done via setup.py, in which case each of the sub-projects are built and installed separately, as mentioned, the super project is just for development convenience.

IDE (Qt Creator) case

When using an IDE, just open the root CMakeLists.txt file as a new project, and make sure to specify the following things:

• LLVM_INSTALL_DIR, the environment variable should point to your libclang library location
• Qt, either select a Qt Kit when configuring the project, or make sure that the qtpaths6 binary is present in the PATH environment variable.
• Python, the PATH environment variable should also point to the Python interpreter which you wish to use for building the projects (can either be a system interpreter, or a virtualenv one for example)

Once that is done, just re-run CMake, so that it picks up the new environment values. If needed, all other cache variables defined by the project files can be re-adjusted (for example FORCE_LIMITED_API).

Command line CMake case

When building using the command line CMake binary, make sure to invoke it in a separate build directory, and not in the root source directory.

Make sure you have the correct environment variables set up, as described in the previous section.

The invocation would then look like:

mkdir build && cd build
cmake -DCMAKE_BUILD_TYPE=Release ..
# make or nmake or msbuild or jom