Focus Highlighting issue with Combo box and Radio Button with Enter Key pressed event

Question

I have been working on PyQt focus method for different widgets whenever Enter key pressed instead of conventional Tab key.

Furthermore, I am able to set focus to the widget which I intended upon Enter key event. However, whenever the focus is on QComboBox or QRadioButton, these two widgets don't seems to highlight like QLineEdit or QPushButton widgets.

I know that I have to set focus policy to StrongFocus and I have tried that and several other methods but unable to fix this issue. Moreover, this behaviour is working perfectly fine and combo box or radio button seems to highlight as well with the Tab key.

Please find below my tried code until now and also snapshot for the actual results.

from PyQt5 import QtCore
from PyQt5.QtWidgets import *
from PyQt5.QtGui import *
from PyQt5.QtCore import *
import sys


class Combo_and_Radio_Focus(QDialog):

    def __init__(self):
        super().__init__()

        # setting title
        self.setWindowTitle("Combo Box Focus Test")

        # setting geometry
        self.setGeometry(600, 200, 650, 400)

        # Some widgets for testing
        self.le1 = QLineEdit(self)
        self.le1.setFixedSize(100, 25)

        self.le2 = QLineEdit(self)
        self.le2.setFixedSize(100, 25)

        self.cbo1 = QComboBox(self)
        self.cbo1.setFixedSize(100, 25)
        self.cbo1.setStyleSheet('QComboBox {background-color: white;}')
        self.cbo1.setFocusPolicy(Qt.StrongFocus)
        self.cbo1.addItems(["", "Item1", "Item2", "Item3"])

        self.cbo2 = QComboBox(self)
        self.cbo2.setFixedSize(100, 25)
        self.cbo2.setStyleSheet('QComboBox {background-color: white;}')
        self.cbo2.setFocusPolicy(Qt.StrongFocus)
        self.cbo2.addItems(["", "Item1", "Item2", "Item3"])

        self.RB1 = QRadioButton("1")
        self.RB1.setChecked(True)
        self.RB1.setFixedSize(100, 20)
        self.RB1.setFocusPolicy(Qt.StrongFocus)

        self.RB2 = QRadioButton("2")
        self.RB2.setFixedSize(100, 20)
        self.RB2.setFocusPolicy(Qt.StrongFocus)

        self.vbl = QVBoxLayout()
        self.vbl.addWidget(self.le1)
        self.vbl.addWidget(self.le2)
        self.vbl.addWidget(self.cbo1)
        self.vbl.addWidget(self.cbo2)
        self.vbl.addWidget(self.RB1)
        self.vbl.addWidget(self.RB2)

        self.setLayout(self.vbl)

        # showing all the widgets
        self.show()

    def keyPressEvent(self, qKeyEvent):
        if int(qKeyEvent.modifiers()) == QtCore.Qt.AltModifier:
            qKeyEvent.ignore()
            return

        if qKeyEvent.key() == QtCore.Qt.Key_Return or qKeyEvent.key() == QtCore.Qt.Key_Enter:
            QWidget.focusNextChild(self)

        else:
            super().keyPressEvent(qKeyEvent)


App = QApplication(sys.argv)
App.setStyle(QStyleFactory.create('Fusion'))

# create the instance of our Window
combo_and_Radio_Focus = Combo_and_Radio_Focus()

# start the app
sys.exit(App.exec())

LineEdit1_Highlighted Below

ComboBox1_Dont_Highlight Below

Answer 1

When the Tab is pressed to make the focus change then the application sets the Qt.WA_KeyboardFocusChange attribute in the window and that is used by the QStyle to make the border painting but since this is not the case then that attribute has to be set directly:

def keyPressEvent(self, qKeyEvent):
    if qKeyEvent.modifiers() & QtCore.Qt.AltModifier:
        qKeyEvent.ignore()
    elif qKeyEvent.key() in (QtCore.Qt.Key_Return, QtCore.Qt.Key_Enter):
        self.focusNextChild()
        self.window().setAttribute(Qt.WA_KeyboardFocusChange)
    else:
        super().keyPressEvent(qKeyEvent)