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[[Category:PySide]]                                                                
[[Category:Qt for Python]]                                                                                                                              
                                                                                   
==Official documentation==
== Install PySide2 ==                                                               
 
                                                                                   
Refer to the [https://doc.qt.io/qtforpython/gettingstarted.html official docs] to start building and using Qt for Python.
You can install PySide2 by building the source package yourself.                   
 
                                                                                   
==Using Qt Creator as a project explorer==                                       
After clonning the official repository you must follow the instructions for         
your specific system.                                                               
                                                                                   
=== Platform Requirements ===                                                      
                                                                                   
'''Python''':                                                                       
* PySide2 supports Python 2 (version >= 2.7 recommended) and Python 3 (version >= 2.5 recommended).
'''Qt''':                                                                             
* Currently, Qt 5.6 and Qt 5.9 onwards are supported (Qt needs to be built with the ''QtXmlPatterns'' module).
* Note that the branch of the [https://code.qt.io/cgit/pyside/pyside-setup.git pyside-setup] repository must match that of the Qt version used.
* PySide versions following 5.6 (so 5.9 and dev) use a C++ parser based on [http://clang.org/ Clang]).·
'''CLANG''':                                                                         
* The Clang library (C-bindings), version 3.9 or higher is required for building.
* Prebuilt versions of it can be downloaded from [http://download.qt.io/development_releases/prebuilt/libclang/ download.qt.io].
'''CMake''':                                                                         
* Required by the building system.                                             
                                                                                   
The building processes are covered in the platform pages.                           
                                                                                   
* [[PySide2_Windows|Windows]]                                                         
* [[PySide2_X11|Linux/X11]]                                                     
* [[PySide2_MacOS| macOS]] 
                                                                                   
==== setup.py build script ====                                                     
                                                                                   
The script ''setup.py'' in the [http://code.qt.io/cgit/pyside/pyside-setup.git/ top level repository] is used to build and install the PySide2 package. It takes a mode argument (''build'' or ''install'') and several options (more options are documented in setup.py itself).·
                                                                                   
The main options are:                                                               
* --qmake=<binary> Path to ''qmake'' of the Qt library to be used                   
* --cmake=<binary> Path to ''cmake''                                               
* --build-tests: Creates a directory containing the tests along with some helper packages
* --ignore-git: Prevents ''setup.py'' from cloning and checking out the submodules.·
* --debug: Build in Debug mode                                                     
* --reuse-build: Rebuilds only modified files (currently does not work for typesystem xml files)
* --openssl: Path to OpenSSL                                                       
* --jobs : Number of threads to use when building                                   
                                                                                   
A typical invocation looks like:                                                   
> python setup.py install --build-tests --jobs=4                                   
                                                                                   
A successful build can be tested by running an example:                             
>  python sources/pyside2-examples/examples/widgets/widgets/tetrix.py               
                                                                                   
You can search for working examples by typing                                       
  cd sources/pyside2-examples                                                       
  git grep "PySide2 port"                                                           
                                                                                   
Note: When doing local builds of Qt on Linux, the environment LD_LIBRARY_PATH needs to be set to point to the location of the Qt library when running examples, as otherwise they are not found by Python. On macOS you will need to set either the DYLD_LIBRARY_PATH or DYLD_FRAMEWORK_PATH environment variables.
                                                                                   
=== Running Tests ===                                                               
                                                                                   
python testrunner.py test  > testlog.txt                                           
                                                                                   
Run only one test(qpainter_test):                                                   
                                                                                   
ctest -R qpainter_test --verbose                                                   
                                                                                   
=== Building the Documentation ===                                                 
                                                                                   
This is currently unexplored terrain [https://bugreports.qt.io/browse/PYSIDE-363 PYSIDE-363].
* The sources are in pyside2/doc                                                   
* libXML2 and libXSLT should be present when building PySide2 (Ubuntu: apt-get install libxml2-dev libxslt1-dev)
* graphviz + dot should be installed                                               
* QT_SRC_DIR needs to be set                                                       
* sphinx should be installed (pip install sphinx)                                   
* qdoc3 is used to generate it                                                     
                                                                                   
                                                                                   
=== Using Qt Creator as a project explorer ===                                       
Qt Creator 4.0+ can be used to open the PySide and Shiboken CMakeLists.txt files as projects, and thus provide usual IDE features for developing PySide - project file navigation, code completion (C++ only), following symbols under cursor (C++ only), syntax highlighting, locator usage, debugging, etc.
Qt Creator 4.0+ can be used to open the PySide and Shiboken CMakeLists.txt files as projects, and thus provide usual IDE features for developing PySide - project file navigation, code completion (C++ only), following symbols under cursor (C++ only), syntax highlighting, locator usage, debugging, etc.
                                                                                      
                                                                                      
Currently there is a limitation that Shiboken has to be built first using the terminal, because the installed shiboken CMake packages will have to be specified for the PySide project in Qt Creator.
Currently, there is a limitation that Shiboken has to be built first using the terminal because the installed shiboken CMake packages will have to be specified for the PySide project in Qt Creator.
                                                                                   
 
The steps for opening the projects in Qt Creator are:                                 
The steps for opening the projects in Qt Creator are:                                 
# Open pyside-setup/sources/shiboken2/CMakeLists.txt, and specify a 5.6 Qt Kit to be used
 
# Build the project as usual (by pressing the build icon for instance)              
#Open '''pyside-setup/sources/shiboken2/CMakeLists.txt''' and specify a 5.12+ Qt Kit to be used
# Open pyside-setup/sources/pyside2/CMakeLists.txt, and specify the same 5.6 Qt Kit
#Build the project as usual (by pressing the '''build''' icon for instance)
# Go to projects tab, and under the Build / CMake section find the Shiboken2_DIR setting. You have to specify the path to the folder where the Shiboken CMake package was installed when you compiled Shiboken from the terminal·
#Open '''pyside-setup/sources/pyside2/CMakeLists.txt''' and specify the same 5.12+ Qt Kit
# An example path under MacOS is /Users/user/Dev/pyside2-setup/pyside_install/py2.7-qt5.6.1-64bit-debug/lib/cmake/Shiboken2-2.0.0. The path has to be adjusted depending on the user folder name, the version of python and qt, etc
#Go to the projects tab, and under the Build / CMake section find the Shiboken2_DIR setting. You have to specify the path to the folder where the Shiboken CMake package was installed when you compiled Shiboken from the terminal·
# (Optional) On MacOS you also have to set the ALTERNATIVE_QT_INCLUDE_DIR setting to the Qt kit include path (e.g. /Users/user/Dev/qt56_source/include)                                                                                                                                                                                                                                                                                                                                  
#An example path under macOS is '''/Users/user/Dev/pyside2-setup/pyside_install/py3.6-qt5.12.1-64bit-debug/lib/cmake/Shiboken2-2.0.0'''. The path has to be adjusted depending on the user folder name, the version of python and qt, etc
# Apply the CMake configuration changes (by pressing the button), and you should be able to build PySide
#(Optional) On MacOS you also have to set the '''ALTERNATIVE_QT_INCLUDE_DIR''' setting to the Qt kit include path (e.g. '''/Users/user/Dev/qt511_source/include''')
#Apply the CMake configuration changes (by pressing the button), and you should be able to build PySide
                                                                                      
                                                                                      
Now you can use the project explorer to look through the source cpp files, python files, use the locator feature to open files and file classes / methods, and other features that Qt Creator provides.
Now you can use the project explorer to look through the source cpp files, python files, use the locator feature to open files and file classes / methods, and other features that Qt Creator provides.
==Troubleshooting / Known Issues==
                                                                                      
                                                                                      
=== Troubleshooting ===                                                             
*Qt 5.9 does not work with OpenSSL 1.1                                         
                                                                                   
**When doing a custom Qt build (some unspecified versions for now), It is necessary to have an OpenSSL version of 1.0.x, since there are compatibility issues with newer versions of OpenSSL ([https://wiki.openssl.org/index.php/OpenSSL_1.1.0_Changes#Qt see details])
* PySide2 5.9 does not work with OpenSSL 1.1                                         
*PySide2 looks at the system installation if the local Qt version does not have a required module
It is necessary to have OpenSSL 1.0.x to work around Qt and PySide v5.9, since there are compatibility issues with newer versions of OpenSSL ([https://wiki.openssl.org/index.php/OpenSSL_1.1.0_Changes#Qt see details])
**The only workaround is to uninstall any module from the system, then PySide2 can look at only the Qt path currently being use.
* PySide2 looks at the system installation if the local Qt version does not have a required module
*Qt packages that directly link to OpenSSL (as opposed to runtime discovery) are not currently supported.
The only workaround is to uninstall any module from the system, then PySide2 can look at only the Qt path currently being use.
*Make sure that the Python environment location where the PySide2 package will be installed is writable (otherwise you might get various permission denied errors). The install location can be found with 99% probability by running:
 
python -c "from distutils.sysconfig import get_python_lib; print(get_python_lib())"
 
*Building failing because graphviz wasn't found. If you're using pyenv and installed it using pip, try to install it using your package manager:<syntaxhighlight>
dnf install graphviz.x86_64 #Fedora
</syntaxhighlight>
*20220727 Urgent update: If you build PySide with a custom built Python, you should build python with the following options: <syntaxhighlight lang="shell">
PYTHON_CONFIGURE_OPTS="--enable-shared --with-trace-refs"
</syntaxhighlight>For example:<syntaxhighlight lang="shell">
PYTHON_CONFIGURE_OPTS="--enable-shared --with-trace-refs" pyenv install -kg 3.9.13
</syntaxhighlight>This makes PySide2 work without the limited API. <br />

Latest revision as of 14:08, 27 July 2022

Official documentation

Refer to the official docs to start building and using Qt for Python.

Using Qt Creator as a project explorer

Qt Creator 4.0+ can be used to open the PySide and Shiboken CMakeLists.txt files as projects, and thus provide usual IDE features for developing PySide - project file navigation, code completion (C++ only), following symbols under cursor (C++ only), syntax highlighting, locator usage, debugging, etc.

Currently, there is a limitation that Shiboken has to be built first using the terminal because the installed shiboken CMake packages will have to be specified for the PySide project in Qt Creator.

The steps for opening the projects in Qt Creator are:

  1. Open pyside-setup/sources/shiboken2/CMakeLists.txt and specify a 5.12+ Qt Kit to be used
  2. Build the project as usual (by pressing the build icon for instance)
  3. Open pyside-setup/sources/pyside2/CMakeLists.txt and specify the same 5.12+ Qt Kit
  4. Go to the projects tab, and under the Build / CMake section find the Shiboken2_DIR setting. You have to specify the path to the folder where the Shiboken CMake package was installed when you compiled Shiboken from the terminal·
  5. An example path under macOS is /Users/user/Dev/pyside2-setup/pyside_install/py3.6-qt5.12.1-64bit-debug/lib/cmake/Shiboken2-2.0.0. The path has to be adjusted depending on the user folder name, the version of python and qt, etc
  6. (Optional) On MacOS you also have to set the ALTERNATIVE_QT_INCLUDE_DIR setting to the Qt kit include path (e.g. /Users/user/Dev/qt511_source/include)
  7. Apply the CMake configuration changes (by pressing the button), and you should be able to build PySide

Now you can use the project explorer to look through the source cpp files, python files, use the locator feature to open files and file classes / methods, and other features that Qt Creator provides.

Troubleshooting / Known Issues

  • Qt 5.9 does not work with OpenSSL 1.1
    • When doing a custom Qt build (some unspecified versions for now), It is necessary to have an OpenSSL version of 1.0.x, since there are compatibility issues with newer versions of OpenSSL (see details)
  • PySide2 looks at the system installation if the local Qt version does not have a required module
    • The only workaround is to uninstall any module from the system, then PySide2 can look at only the Qt path currently being use.
  • Qt packages that directly link to OpenSSL (as opposed to runtime discovery) are not currently supported.
  • Make sure that the Python environment location where the PySide2 package will be installed is writable (otherwise you might get various permission denied errors). The install location can be found with 99% probability by running:
python -c "from distutils.sysconfig import get_python_lib; print(get_python_lib())"
  • Building failing because graphviz wasn't found. If you're using pyenv and installed it using pip, try to install it using your package manager:
    dnf install graphviz.x86_64 #Fedora
  • 20220727 Urgent update: If you build PySide with a custom built Python, you should build python with the following options: 
    PYTHON_CONFIGURE_OPTS="--enable-shared --with-trace-refs"
    For example:
    PYTHON_CONFIGURE_OPTS="--enable-shared --with-trace-refs" pyenv install -kg 3.9.13
    This makes PySide2 work without the limited API.
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