from PySide6.QtCore import QTimer, QObject
from PySide6.QtGui import QStandardItemModel
from PySide6.QtWidgets import QApplication, QComboBox, QVBoxLayout, QWidget

class Watcher(QObject):
    def __init__(self, parent: QWidget):
        super().__init__(parent)
        parent.installEventFilter(self)

    def eventFilter(self, watched, event):
        print(watched.objectName(), event)
        return super().eventFilter(watched, event)

class MainWindow(QWidget):
    def __init__(self):
        super().__init__()
        self.setObjectName('-- mainwin --')
        self.combo = QComboBox()
        self.combo.setModel(QStandardItemModel())
        layout = QVBoxLayout()
        layout.addWidget(self.combo)
        self.setLayout(layout)
        self.watcher = Watcher(self)
        self.timer = QTimer(self)
        self.timer.timeout.connect(self.test)
        self.timer.start(100)

    def test(self):
        sels = [1,2,3,4,5,6]
        cbx = self.combo
        model = cbx.model()
        cbx.clear()
        cbx.insertItems(0, [f'Item.{no}' for no in sels])
        for (idx, no) in enumerate(sels):
            itm = model.item(idx)
            print(f'set model item {idx=} {no=} {itm=}')

if __name__ == "__main__":   
    app = QApplication()    
    window = MainWindow()    
    window.show()    
    app.exec() 

-- mainwin -- <PySide6.QtCore.QEvent(QEvent::Paint)>
-- mainwin -- <PySide6.QtGui.QMouseEvent(NonClientAreaMouseMove ts=876234656 pos=99,-3 scn=99,-3 gbl=2659,175 dev=QInputDevice(QPointingDevice("core pointer" Mouse id=1 buttonCount=3))>
-- mainwin -- <PySide6.QtCore.QEvent(QEvent::Leave)>
-- mainwin -- <PySide6.QtGui.QMouseEvent(NonClientAreaMouseMove ts=876234656 pos=95,-7 scn=95,-7 gbl=2655,171 dev=QInputDevice(QPointingDevice("core pointer" Mouse id=1 buttonCount=3))>
-- mainwin -- <PySide6.QtGui.QMouseEvent(NonClientAreaMouseMove ts=876234671 pos=88,-14 scn=88,-14 gbl=2648,164 dev=QInputDevice(QPointingDevice("core pointer" Mouse id=1 buttonCount=3))>
-- mainwin -- <PySide6.QtGui.QMouseEvent(NonClientAreaMouseMove ts=876234671 pos=82,-19 scn=82,-19 gbl=2642,159 dev=QInputDevice(QPointingDevice("core pointer" Mouse id=1 buttonCount=3))>
-- mainwin -- <PySide6.QtGui.QMouseEvent(NonClientAreaMouseMove ts=876234687 pos=74,-23 scn=74,-23 gbl=2634,155 dev=QInputDevice(QPointingDevice("core pointer" Mouse id=1 buttonCount=3))>
-- mainwin -- <PySide6.QtGui.QMouseEvent(NonClientAreaMouseMove ts=876234687 pos=70,-25 scn=70,-25 gbl=2630,153 dev=QInputDevice(QPointingDevice("core pointer" Mouse id=1 buttonCount=3))>
-- mainwin -- <PySide6.QtGui.QMouseEvent(NonClientAreaMouseMove ts=876234703 pos=69,-25 scn=69,-25 gbl=2629,153 dev=QInputDevice(QPointingDevice("core pointer" Mouse id=1 buttonCount=3))>
-- mainwin -- <PySide6.QtGui.QMouseEvent(NonClientAreaMouseMove ts=876234703 pos=69,-26 scn=69,-26 gbl=2629,152 dev=QInputDevice(QPointingDevice("core pointer" Mouse id=1 buttonCount=3))>
-- mainwin -- <PySide6.QtGui.QMouseEvent(NonClientAreaMouseMove ts=876234734 pos=69,-28 scn=69,-28 gbl=2629,150 dev=QInputDevice(QPointingDevice("core pointer" Mouse id=1 buttonCount=3))>
-- mainwin -- <PySide6.QtGui.QMouseEvent(NonClientAreaMouseMove ts=876234750 pos=69,-29 scn=69,-29 gbl=2629,149 dev=QInputDevice(QPointingDevice("core pointer" Mouse id=1 buttonCount=3))>
-- mainwin -- <PySide6.QtGui.QMouseEvent(NonClientAreaMouseMove ts=876234750 pos=70,-30 scn=70,-30 gbl=2630,148 dev=QInputDevice(QPointingDevice("core pointer" Mouse id=1 buttonCount=3))>
set model item idx=0 no=1 itm=<PySide6.QtGui.QStandardItem object at 0x000001BE7186FC00>
set model item idx=1 no=2 itm=<PySide6.QtGui.QStandardItem object at 0x000001BE718742C0>
set model item idx=2 no=3 itm=<PySide6.QtGui.QStandardItem object at 0x000001BE71874280>
set model item idx=3 no=4 itm=<PySide6.QtGui.QStandardItem object at 0x000001BE718743C0>
set model item idx=4 no=5 itm=<PySide6.QtGui.QStandardItem object at 0x000001BE71874040>
set model item idx=5 no=6 itm=<PySide6.QtGui.QStandardItem object at 0x000001BE7186EF40>
-- mainwin -- <PySide6.QtGui.QStandardItem object at 0x000001BE7186FB40>
Error calling Python override of QObject::eventFilter(): Traceback (most recent call last):
  File "C:\Users\user\jobs\works\mtcs\test\test_cbx_model.py", line 15, in eventFilter
    return super().eventFilter(watched, event)
TypeError: 'PySide6.QtCore.QObject.eventFilter' called with wrong argument types:
  PySide6.QtCore.QObject.eventFilter(MainWindow, QStandardItem)
Supported signatures:
  PySide6.QtCore.QObject.eventFilter(watched: PySide6.QtCore.QObject, event: PySide6.QtCore.QEvent, /)