PyCharm loadUi findChild - unresolved attribute reference [duplicate] - pyqt6

Question

Let's say I have a ui file created in Qt Designer that I want to load dynamically to then manipulate the widgets, such as:
example.py:
from PyQt5 import QtWidgets, uic
class MyWidget(QtWidgets.QWidget):
def __init__(self, parent=None):
super(MyWidget, self).__init__(parent)
uic.loadUi('example.ui', self)
# No code completion here for self.myPushButton:
self.myPushButton.clicked.connect(self.handleButtonClick)
self.show()
Is there a standard / convenient way of enabling code completion for the widgets loaded this way in PyCharm (2017.1.4)?
At the moment I am using this (written in the constructor after the ui file is loaded):
self.myPushButton = self.myPushButton # type: QtWidgets.QPushButton
# Code completion for myPushButton works at this point
I also thought of this, but it does not seem to do the trick:
assert isinstance(self.myPushButton, QtWidgets.QPushButton)
# PyCharm does not even recognise myPushButton as an attribute of self at this point
Finally, I also thought of using python stubs, such as:
example.pyi:
class MyWidget(QtWidgets.QWidget):
def __init__(self):
self.myPushButton: QtWidgets.QPushButton = ...
However, myPushButton is properly recognised in code outside example.py but not in code inside example.py itself, which is kind of the opposite of what I wanted.
I am also considering taking my first approach but with all those lines put in a private method that will never get called, such as:
example.py:
from PyQt5 import QtWidgets, uic
class MyWidget(QtWidgets.QWidget):
def __init__(self, parent=None):
super(MyWidget, self).__init__(parent)
uic.loadUi('example.ui', self)
# Code completion now works here for self.myPushButton:
self.myPushButton.clicked.connect(self.handleButtonClick)
self.show()
def __my_private_method_never_called():
self.myPushButton = self.myPushButton # type: QtWidgets.QPushButton
# Or even this (it should have the same effect if this
# function is never called, plus it is less verbose):
self.myPushButton = QtWidgets.QPushButton()
# If I want to make sure that this is never called
# could raise an error at some point:
raise YouShouldNotHaveCalledThisError()
This seems to work fine, and it also allows me to group all my type hinting code together, isolated from the rest. I could even make some script to write all those lines for me by parsing the ui files. I am just wondering if people reading my code would find this approach very unorthodox, even if I comment clearly why am I writing a technically useless private function.

Answer 1

If anybody is interested, I made the script I mentioned to parse the .ui files and generate stub code ready to be copied to my class:
ui_stub_generator.py:
from __future__ import print_function
import os
import sys
import xml.etree.ElementTree
def generate_stubs(file):
root = xml.etree.ElementTree.parse(file).getroot()
print('Stub for file: ' + os.path.basename(file))
print()
print(' def __stubs(self):')
print(' """ This just enables code completion. It should never be called """')
for widget in root.findall('.//widget'):
name = widget.get('name')
if len(name) > 3 and name[:2] == 'ui' and name[2].isupper():
cls = widget.get('class')
print(' self.{} = QtWidgets.{}()'.format(
name, cls
))
print(' raise AssertionError("This should never be called")')
print()
def main():
for file in sys.argv[1:]:
generate_stubs(file)
if __name__ == '__main__':
main()
This only parses widgets whose names start with 'ui' followed by an uppercase letter, such as 'uiMyWidget', which is the naming convention that I typically follow in the Qt Designer. By doing this, the widgets with names automatically generated by the Qt Designer are ignored (if I cared about these, I would have given them a proper name). It should be straightforward to update this for any other naming conventions, or other type of objects, such as actions.
For convenience, I have set this up as an external tool in PyCharm as well; see screenshot here (change the paths as appropriate). That way, I only have to right-click my ui file in the project window, then External Tools -> Stub Generator for Qt UI Files, and I get the following output in the Run window ready to be copied:
C:\ProgramData\Anaconda3\python.exe D:\MyProject\bin\ui_stub_generator.py D:\MyProject\my_ui_file.ui
Stub for file: my_ui_file.ui
def __stubs(self):
""" This just enables code completion. It should never be called """
self.uiNameLabel = QtWidgets.QLabel()
self.uiOpenButton = QtWidgets.QPushButton()
self.uiSplitter = QtWidgets.QSplitter()
self.uiMyCombo = QtWidgets.QComboBox()
self.uiDeleteButton = QtWidgets.QPushButton()
raise AssertionError("This should never be called")
Process finished with exit code 0