How to add plugins to PySide6-designer?

Tim Tu

Hi all,
I'm trying to add some Custom Widgets into PySide6-designer, but I don't know how to make designer load them. Here is a python script that's work well on PyQt5. I want to make it work on PySide6, so I simply replaced PyQt5 to PySide6, but it doesn't work.

When I check Plugin Information, I found this:

Please help me, thanks.

Tim Tu

I finally made it work!

Thank everyone for your help.

friedemannkleint

See https://doc.qt.io/qtforpython-6/tutorials/basictutorial/uifiles.html#designer-custom-widgets and the task menu example https://doc.qt.io/qtforpython-6/examples/example_designer_taskmenuextension.html

Note you need to launch pyside6-designer for this to work.

Tim Tu

@friedemannkleint Thanks! I have written the register.py, but now designer can't start. (Also, I have tried the example, it doesn't work too.)

❯ export PYSIDE_DESIGNER_PLUGINS="registertictactoe.py"
❯ pyside6-designer
Traceback (most recent call last):
  File "/home/tim/mambaforge/envs/aligner/bin/pyside6-designer", line 8, in <module>
    sys.exit(designer())
  File "/home/tim/mambaforge/envs/aligner/lib/python3.10/site-packages/PySide6/scripts/pyside_tool.py", line 181, in designer
    qt_tool_wrapper(ui_tool_binary("designer"), sys.argv[1:])
  File "/home/tim/mambaforge/envs/aligner/lib/python3.10/site-packages/PySide6/scripts/pyside_tool.py", line 52, in qt_tool_wrapper
    pyside_dir = Path(ref_mod.__file__).resolve().parent
  File "/home/tim/mambaforge/envs/aligner/lib/python3.10/pathlib.py", line 960, in __new__
    self = cls._from_parts(args)
  File "/home/tim/mambaforge/envs/aligner/lib/python3.10/pathlib.py", line 594, in _from_parts
    drv, root, parts = self._parse_args(args)
  File "/home/tim/mambaforge/envs/aligner/lib/python3.10/pathlib.py", line 578, in _parse_args
    a = os.fspath(a)
TypeError: expected str, bytes or os.PathLike object, not NoneType

JonB

@Tim-Tu said in How to add plugins to PySide6-designer?:

export PYSIDE_DESIGNER_PLUGINS="registertictactoe.py"

Per the docs https://doc-snapshots.qt.io/qtforpython-dev/tutorials/basictutorial/uifiles.html#custom-widgets-in-qt-designer

Registering this with Qt Designer is done by providing a registration script named register*.py and pointing the path-type environment variable PYSIDE_DESIGNER_PLUGINS to the directory.

"to the directory". So try export PYSIDE_DESIGNER_PLUGINS="." or the full path.

Tim Tu

@JonB Thanks, that is my wrong.

But that maybe pyside's bug. I have checked the code, and I found it tried to get the path of pyside6 by pyside_dir = Path(ref_mod.__file__).resolve().parent . But actually it just returns None.

>>> import PySide6
>>> print(PySide6.__file__)
None

I can solve this problem by creating __init__.py at /site-packages/PySide6/. Should I report this problem?

JonB

@Tim-Tu
I only have PySide2:

>>> import PySide2
>>> print(PySide2.__file__)
/home/jon/.local/lib/python3.10/site-packages/PySide2/__init__.py

I don't know why your PySide6 does not have this, or what you are supposed to do about it.

Tim Tu

Unluckily, it still can't work.

 ❯ ll
total 28K
-rw-rw-r-- 1 tim tim  435 Feb 16 09:24 main.py
-rw-rw-r-- 1 tim tim  446 Feb 16 09:24 registertictactoe.py
-rw-rw-r-- 1 tim tim  119 Feb 16 09:24 taskmenuextension.pyproject
-rw-rw-r-- 1 tim tim 4.9K Feb 16 09:24 tictactoe.py
-rw-rw-r-- 1 tim tim 1.7K Feb 16 09:24 tictactoeplugin.py
-rw-rw-r-- 1 tim tim 2.3K Feb 16 09:24 tictactoetaskmenu.py
❯ export PYSIDE_DESIGNER_PLUGINS="."
❯ pyside6-designer
ERROR: ld.so: object 'libpython3.10.so' from LD_PRELOAD cannot be preloaded (cannot open shared object file): ignored.

JonB

@Tim-Tu
Dunno. Verify locate libpython3.10.so returns some matches (mine returns a dozen). Whether the error message means it cannot find it or it can but cannot load it (check output from ldd) I do not know. Nor whether ignored means it doesn't matter. I'm afraid I don't use this stuff.

Tim Tu

It finally work on python 3.11.

Tim Tu

It still doesn't work on my code, here is my register_widgets.py:

from PySide6.QtDesigner import QPyDesignerCustomWidgetCollection
import os, sys
from pathlib import Path
import qfluentwidgets

plugins_dir = os.path.dirname(qfluentwidgets.__file__) + '/plugins'
sys.path.append(plugins_dir)
print(plugins_dir)
# plugins = []

def get_modules(py):
    # I don't know why, but they are nessary
    from PySide6.QtDesigner import QDesignerCustomWidgetInterface
    from inspect import getmembers

    modules = []
    for name, obj in getmembers(py):
    # for name, obj in py.__dict__.items():
        print(f"Loading {name}")
        if isinstance(obj, QDesignerCustomWidgetInterface):
            modules.append(obj)
    return modules

for filename in os.listdir(plugins_dir):
    if filename.endswith('.py') and not filename.startswith('_'):
        # plugins += get_modules(__import__(file_path))
        py = __import__(f"qfluentwidgets.plugins.{filename}".replace('.py', ''))
        for plug in get_modules(py):
            QPyDesignerCustomWidgetCollection.addCustomWidget(plug)

Tim Tu

I finally made it work!

Thank everyone for your help.

Hassaan11

@Tim-Tu
Hey!
Sorry for replying to a closed topic, but would be so kind as to provide me with the code you used to register the plugin? I am also trying to get qfluentwidgets to work on my designer but having some problems, this would save a lot of trouble!
Thanks

Tim Tu

@Hassaan11 Hi, I'm sorry for my late reply. Should you still require the information, kindly visit my repository.

AndreBam

@JonB Just following the tutorial here https://doc.qt.io/qtforpython-6/examples/example_designer_taskmenuextension.html#task-menu-extension-example. I'm wondering if it's possible to have the required files in different directories.

JonB

@AndreBam I don't use designer plugins, let alone PySide/PySide6, so I'm not the person to ask.