PyQt6: Popup QMainWindow sometimes ignoring ("missing") clicks even if opened and activated

[1st-alex]

I’m building a macOS menu bar extra (a.k.a. system tray) app using PyQt6. When clicking the menu bar icon, a popup window appears, which is a QMainWindow with the Qt.WindowType.Popup window flag set.

I’m noticing sporadic issues where the popup window doesn't respond to clicks even though it's open. Sometimes, clicking on a QPushButton inside the popup, or an action on the QMenu, causes it to close abruptly without the clicked signal being invoked on the button or the triggered action on a menu item (i.e., clicks are sometimes being “missed”). The popup window contains a QTreeWidget which I’ve styled with QSS so that hovering over a QTreeWidgetItem will cause it to be highlighted; sometimes the highlight doesn’t appear, suggesting that the open popup window is ignoring user interaction. Switching between windows from other open applications and then clicking the menu bar icon for my app sometimes causes the issue to occur.

The issue is reproducible on macOS 15 Sequoia and macOS 26 Tahoe, using a mouse (on a Mac Mini) and a trackpad (on a MacBook Air). I'm using PyQt6 version 6.11.0, and Python 3.14.4. The app is distributed as a PyInstaller build, but I've noticed this issue sometimes occurring on my dev machine, where the app is executed directly from the Python interpreter.

I tried calling the activateWindow() method on the QMainWindow object for the popup window, as well as calling grabMouse() (and releaseMouse() in the overridden method closeEvent()). I also ensured that the widgets within the popup window have its self object passed to their constructors. But the issue is still occurring.

What should I be doing to ensure that the popup window is consistently capturing mouse input when it’s opened? What gotchas and caveats that I missed that could be causing this issue?

[SGaist]

Hi and welcome to devnet,

Do you have the same issue if using PySide6 ?
Can you share a minimal script that shows this issue ?

[1st-alex]

Issue is reproducible in PySide6. Below is the source code for a demo app; it should be executed on macOS 13 Ventura or newer. Also included is an image file to use as the menu bar extra icon.

Again, this is a sporadic issue, so you may have to try it a few times to cause the issue to occur. Switching between windows from other open applications and then clicking the menu bar icon for my app may cause it to happen.

demo.py:

import sys
from PySide6.QtWidgets import QApplication
from SamplePopupWnd import SamplePopupWnd

mainwnd = None

def main():
    global mainwnd
    app = QApplication(sys.argv)
    app.setQuitOnLastWindowClosed(False)
    mainwnd = SamplePopupWnd()
    sys.exit(app.exec())

main()

SamplePopupWnd.py:

import sys
from PySide6.QtCore import Qt, QPoint, QSize
from PySide6.QtGui import QIcon, QAction, QGuiApplication
from PySide6.QtWidgets import (QWidget, QMenu, QSystemTrayIcon, QHBoxLayout, QPushButton,
    QMessageBox, QMainWindow)

class SamplePopupWnd(QMainWindow):
    def __init__(self):
        super().__init__()
        self.popupwidth = 300
        self.popupheight = 400

        # Menu bar extra icon.
        icon = self.getSystemTrayIcon()
        self.systray = QSystemTrayIcon()
        self.systray.setIcon(icon)
        self.systray.setVisible(True)
        self.systray.activated.connect(self.togglePopup)

        self.button = QPushButton("button", self)
        self.button.clicked.connect(self.showButtonMessage)

        # Actions for a menu that is opened by a menu button
        self.settings = QAction("settings", self)
        self.settings.triggered.connect(self.showMenuMessage)
        self.about_act = QAction("about", self)
        self.about_act.triggered.connect(self.aboutActionSelected)
        self.quit_act = QAction("quit", self)
        self.quit_act.triggered.connect(self.quitActionSelected)

        self.menu = QMenu(self)
        self.menu.addAction(self.settings)
        self.menu.addAction(self.about_act)
        self.menu.addSeparator()
        self.menu.addAction(self.quit_act)
        self.menubutton = QPushButton("≡ menu", self)
        self.menubutton.setMenu(self.menu)

        hbox = QHBoxLayout(self)
        hbox.addWidget(self.button)
        hbox.addStretch(2)
        hbox.addWidget(self.menubutton)

        # Add to a QWidget that is styled with rounded corners.
        self.popup = QWidget(self)
        self.popup.setObjectName("popup")
        self.popup.resize(QSize(self.popupwidth, self.popupheight))
        self.popup.setLayout(hbox)

        self.setAttribute(Qt.WidgetAttribute.WA_TranslucentBackground, True)
        self.setWindowFlags(Qt.WindowType.Popup)
        self.setGeometry(200, 100, self.popupwidth, self.popupheight)
        self.setStyleSheet("""
            #popup {
                border-radius: 16px;
                background-color: #fefefe;
            }
        """)

    def showButtonMessage(self):
        QMessageBox.information(self, "demo", "the Button was clicked!", QMessageBox.StandardButton.Ok)

    def showMenuMessage(self):
        QMessageBox.information(self, "demo", "the Menu Action was clicked!", QMessageBox.StandardButton.Ok)

    def aboutActionSelected(self):
        QMessageBox.about(self, "about", "qt for python popup demo 1.0")

    def quitActionSelected(self):
        sys.exit()

    def getSystemTrayIcon(self):
        icon = QIcon("systray.png")
        return icon

    def togglePopup(self, reason):
        # Handle click on system tray icon.
        if reason == QSystemTrayIcon.ActivationReason.Trigger:
            if self.isVisible():
                self.close()
            else:
                self.openPopup()

    def openPopup(self):
        systray_geom = self.systray.geometry()
        x = systray_geom.x()
        y = 0 if systray_geom.y() < 0 else systray_geom.y()
        currscreen = QGuiApplication.screenAt(QPoint(x, y))
        screen_avail_geom = currscreen.availableGeometry()
        top = screen_avail_geom.y()
        left1 = systray_geom.x()
        left2 = screen_avail_geom.width() - self.popupwidth

        # Align popup left coords with the system tray icon.
        left = left1 if left1 < left2 else left2
        self.setGeometry(left, top, self.popupwidth, self.popupheight)
        self.show()
        self.activateWindow()

systray.png: