[Python] PyQt emit signals not received (or emitted?)

I am brand new to PyQt and I am trying to create a small GUI for transferring files which essentially shows the progress of the transfer.

Problem


I am trying to figure out why my signals are not received by my handler methods (of the main UI class): updateProgress, logFileChange, updateFileLocations. I can print the signals right before they are emitted but do not see them come in. What am I doing wrong?

Code


from PyQt6 import QtWidgets, uic
from PyQt6 import QtCore
import sys
from shutil import rmtree, copy2, copytree
from pathlib import Path
from glob import glob

from PyQt5.QtCore import QObject, QThread, pyqtSignal

class Transfer(QThread):
# This signal will be used to update the UI
progress_signal = pyqtSignal(int)
progress_log = pyqtSignal(str)
finished = pyqtSignal(dict)

def __init__(self, transferItems, tempDir, parent = None):
super().__init__(parent)
self.transferItems = transferItems
self.tempDir = tempDir
self.transferProgress = 0

def enumerateFiles(self):
self.f_dict = {}
for item in self.transferItems:
if item.is_dir():
items = glob(f"{item}/**/*", recursive=True)
for item in items:
item = Path(item)
if item.is_file():
self.f_dict.update( {item: item.stat().st_size} )
else:
self.f_dict.update( {item: item.stat().st_size} )

self.transferSize = sum(self.f_dict.values())

def transferLocal(self):

def customCopy(src, dst):
self.transferProgress += self.f_dict[Path(src)]
# Change dictionary key here
self.f_dict[Path(dst)] = self.f_dict.pop(Path(src))
self.progress_log.emit(f'Copying {src} -> {dst}')
base = 10000 # Make sure this matches the definition in the .ui
print(int(min(base, self.transferProgress / self.transferSize * base)), end='\r')
self.progress_signal.emit( int(min(base, self.transferProgress / self.transferSize * base)) )
# Dont actually copy for now
# copy2(src, dst)

for source in self.transferItems:
copytree(source, self.tempDir / source.name, copy_function=customCopy)

self.finished.emit(self.f_dict)

def run(self):
self.enumerateFiles()
self.transferLocal()


class Ui(QtWidgets.QMainWindow):
def __init__(self, items):
super(Ui, self).__init__()
uic.loadUi(r"C:\Users\...\progress.ui", self)
self.show()

self.transferItems = items
self.tempDir = Path(r"C:\Users\...\TEMP")

QtWidgets.QApplication.setStyle(QtWidgets.QStyleFactory.create('Windows11'))

# Create worker
self.worker = Transfer(self.transferItems, self.tempDir)

# Connect Signals
self.worker.progress_signal.connect(self.updateProgress)
self.worker.progress_log.connect(self.logFileChange)
self.worker.finished.connect(self.updateFileLocations)

# Start thread
self.worker.start()

# Dont change this function name - control red-x close behavior
def closeEvent(self, event):
self.worker.quit()
event.accept()

def updateFileLocations(self, f_dict):
# self.Confirm.setEnabled(True)
self.f_dict = f_dict

def updateProgress(self, val):
print("Incoming", val)
self.Progress.setValue(val)

def logFileChange(self, log_entry):
print("Incoming", log_entry)
self.Console.append(log_entry)

sources = [Path(r"C:\Users\...")]
# sources = sys.argv[1:]

app = QtWidgets.QApplication(sys.argv)
window = Ui(sources)
window.show()
sys.exit(app.exec())


And here is the GUI XML:

<?xml version="1.0" encoding="UTF-8"?>
<ui version="4.0">
<class>MainWindow</class>
<widget class="QMainWindow" name="MainWindow">
<property name="geometry">
<rect>
<x>0</x>
<y>0</y>
<width>810</width>
<height>700</height>
</rect>
</property>
<property name="minimumSize">
<size>
<width>810</width>
<height>700</height>
</size>
</property>
<property name="maximumSize">
<size>
<width>810</width>
<height>700</height>
</size>
</property>
<property name="windowTitle">
<string>AFT Automator</string>
</property>
<property name="windowOpacity">
<double>1.000000000000000</double>
</property>
<widget class="QWidget" name="centralwidget">
<widget class="QProgressBar" name="Progress">
<property name="geometry">
<rect>
<x>10</x>
<y>10</y>
<width>781</width>
<height>51</height>
</rect>
</property>
<property name="font">
<font>
<pointsize>12</pointsize>
</font>
</property>
<property name="value">
<number>0</number>
</property>
</widget>
<widget class="QTextBrowser" name="textBrowser">
<property name="geometry">
<rect>
<x>20</x>
<y>80</y>
<width>711</width>
<height>191</height>
</rect>
</property>
</widget>
</widget>
<widget class="QMenuBar" name="menubar">
<property name="enabled">
<bool>true</bool>
</property>
<property name="geometry">
<rect>
<x>0</x>
<y>0</y>
<width>810</width>
<height>21</height>
</rect>
</property>
</widget>
<widget class="QStatusBar" name="statusbar"/>
</widget>
<resources/>
<connections/>
</ui>


EDIT: Of note, if I use the @pyqtSlot decorator on my methods, the whole program crashes.

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