from PySide2 import (QtCore, QtGui, QtWidgets)
from table_model import CustomTableModel

class TextBoxDelegate(QtWidgets.QItemDelegate):

    def __init__(self):
        QtWidgets.QItemDelegate.__init__(self)
        # some code skipped

class EditorView(QtWidgets.QTableView):
    ''' Subclassing QTableview for reimplementing keyPressEvent '''

    def keyPressEvent(self, event):

        print(event.key())
        # (!!!) QtCore.Qt.Key_Down event ignored here (!!!)

    def __init__(self, source_data = None, translated_data = None):
        QtWidgets.QTableView.__init__(self)

        # CustomTableModel
        self.model = CustomTableModel(source_data, translated_data)
        self.setModel(self.model)
        self.setEditTriggers(QtWidgets.QAbstractItemView.AllEditTriggers)



class Widget(QtWidgets.QWidget):

    def __init__(self, source_data = None, translated_data = None):
        QtWidgets.QWidget.__init__(self)

        self.tableView = EditorView(source_data, translated_data)
        delegate = TextBoxDelegate()
        self.tableView.setItemDelegate(delegate)

        # Another code ignored here