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QAxWidget glitches when resizing GUI window

I am currently exploring the possibilities of displaying and working with PowerPoint presentations in a GUI using PyQt5/PyQt6 and Python. For that I found the most promising solution to be using a QAxWidget. Loading and displaying the pptx-file works fine, but unfortunately I noticed glitches when resizing the window of the GUI.
As a minimal example I used the following tutorial from the official Qt docs:
https://doc.qt.io/qtforpython/examples/example_axcontainer__axviewer.html?highlight=qaxwidget
After the QAxWidget()-initialization i just added the following line:
self.axWidget.setControl(r"C:\path\to\file\presentation.pptx")
Full code (taken from: https://doc.qt.io/qtforpython/examples/example_axcontainer__axviewer.html?highlight=qaxwidget):
# Copyright (C) 2022 The Qt Company Ltd.
# SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
"""PySide6 Active Qt Viewer example"""
import sys
from PyQt5.QtWidgets import qApp
from PySide6.QtAxContainer import QAxSelect, QAxWidget
from PySide6.QtGui import QAction
from PySide6.QtWidgets import (QApplication, QDialog,
QMainWindow, QMessageBox, QToolBar)
class MainWindow(QMainWindow):
def __init__(self):
super().__init__()
toolBar = QToolBar()
self.addToolBar(toolBar)
fileMenu = self.menuBar().addMenu("&File")
loadAction = QAction("Load...", self, shortcut="Ctrl+L", triggered=self.load)
fileMenu.addAction(loadAction)
toolBar.addAction(loadAction)
exitAction = QAction("E&xit", self, shortcut="Ctrl+Q", triggered=self.close)
fileMenu.addAction(exitAction)
aboutMenu = self.menuBar().addMenu("&About")
aboutQtAct = QAction("About &Qt", self, triggered=qApp.aboutQt)
aboutMenu.addAction(aboutQtAct)
self.axWidget = QAxWidget()
self.axWidget.setControl(r"C:\path\to\file\presentation.pptx")
self.setCentralWidget(self.axWidget)
def load(self):
axSelect = QAxSelect(self)
if axSelect.exec() == QDialog.Accepted:
clsid = axSelect.clsid()
if not self.axWidget.setControl(clsid):
QMessageBox.warning(self, "AxViewer", f"Unable to load {clsid}.")
if __name__ == '__main__':
app = QApplication(sys.argv)
mainWin = MainWindow()
availableGeometry = mainWin.screen().availableGeometry()
mainWin.resize(availableGeometry.width() / 3, availableGeometry.height() / 2)
mainWin.show()
sys.exit(app.exec())
When resizing the window of the GUI, there appear some glitches underneath:
An animation that shows the result while resizing:
Unfortunately I haven't found many resources I could use where a QAxWidget is used in combination with Python to figure this out myself. That's why I'm here to ask if anyone out there might have a solution for getting rid of those glitches.

I got rid of the glitches by installing an event filter to the QAxWidget using self.axWidget.installEventFilter(self).
This will call the eventFilter()-method of the QMainWindow which I set up like this: (ReportDefinitionTool is the subclass of QMainWindow here.)
def eventFilter(self, widget: QWidget, event: QEvent):
if event.type() == QEvent.Resize and widget is self.pptx_axwidget:
self.pptx_axwidget.setFixedHeight(int(self.pptx_axwidget.width() / 16 * 9))
return super(ReportDefinitionTool, self).eventFilter(widget, event)
Since the PowerPoint-presentation is displayed in a 16:9 format, this will make sure the QAxWidget does only occupy this space. The glitchy space from the initial question came from the unused space of the QAxWidget.

PyQt5 buttons not connecting

I am trying to build a simple GUI using PyQT5, with 3 buttons to open file browsers and one more to run processing with the selected files, but I can't get my buttons to connect to the functions needed to carry this out.
In the Ctrl class, the _connect_signals function doesn't seem to be calling _input_select. Can anyone help me figure out why?
import sys
# Import QApplication and the required widgets from PyQt5.QtWidgets
from PyQt5.QtWidgets import QApplication
from PyQt5.QtWidgets import QMainWindow
from PyQt5.QtWidgets import QPushButton
from PyQt5.QtWidgets import QVBoxLayout
from PyQt5.QtWidgets import QWidget
from PyQt5.QtWidgets import QFileDialog
# Create a subclass of QMainWindow to setup the calculator's GUI
class UI(QMainWindow):
"""App's View (GUI)."""
def __init__(self):
"""View initializer."""
super().__init__()
# Set some main window's properties
self.setFixedSize(300, 150)
# Set the central widget and the general layout
self.generalLayout = QVBoxLayout()
self._centralWidget = QWidget(self)
self.setCentralWidget(self._centralWidget)
self._centralWidget.setLayout(self.generalLayout)
# Create the buttons
self._create_buttons()
def _create_buttons(self):
"""Create the buttons."""
self.buttons = {}
buttons_layout = QVBoxLayout()
# Button text | position on the QVBoxLayout
buttons = {
"Select input file...": 0,
"Select config file...": 1,
"Select output file...": 2,
"Run": 3,
}
# Create the buttons and add them to the grid layout
for btnText, pos in buttons.items():
self.buttons[btnText] = QPushButton(btnText)
buttons_layout.addWidget(self.buttons[btnText], pos)
# Add buttons_layout to the general layout
self.generalLayout.addLayout(buttons_layout)
# Create a Controller class to connect the GUI and the model
class Ctrl:
"""App's Controller."""
def __init__(self, setup, view):
"""Controller initializer."""
self._view = view
self._setup = setup
# Connect signals and slots
self._connect_signals()
def _input_select(self): # Not being called
print("input selection")
options = QFileDialog.Options()
file_select, _ = QFileDialog.getOpenFileNames(
self,
'Select Input File...',
'',
'CSV Files (*.csv);;All Files (*)',
options=options
)
if file_select:
self._setup["input"] = file_select
def _connect_signals(self):
"""Connect signals and slots."""
self._view.buttons["Select input file..."].clicked.connect(self._input_select) # Not working!
# Client code
def main():
"""Main function."""
# Create an instance of `QApplication`
app = QApplication(sys.argv)
# Show the app's GUI
view = UI()
view.show()
setup = {}
# Create instance of the controller
Ctrl(setup=setup, view=view)
# Execute app's main loop
sys.exit(app.exec_())
if __name__ == "__main__":
main()
In case it helps, I started out by butchering this example code from a Real Python tutorial, but must have broken it along the way.

The problem is that you are not keeping any persistent reference to the Ctrl() instance you are creating. This results in python garbage collecting it as soon as the instance is created.
To solve the issue, just assign it to a variable:
def main():
"""Main function."""
# Create an instance of `QApplication`
app = QApplication(sys.argv)
# Show the app's GUI
view = UI()
view.show()
setup = {}
# Create instance of the controller
ctrl = Ctrl(setup=setup, view=view)
# Execute app's main loop
sys.exit(app.exec_())
Some considerations:
while separating logic from interface is usually good practice, it's a concept that needs to be used with care, as sometimes it only makes things more complex than they should be. Most of the times (especially with simple programs), it only makes a bigger codebase without giving any actual benefit: it's harder to read and to debug, and you'll probably end up continuously switching from the logic parts and the ui parts of your code;
your code shows one of the drawback of that concept: when you create the file dialog, you're using self, but in that case it refers to the Ctrl instance, while the argument should be the UI instance instead (which will result in a crash, as Qt will get an unexpected argument type); you can use self._view instead, but, as said, the whole separation in this case just makes things unnecessarily complex;
using strings for dictionary keys that refer to internal objects is rarely a good idea (especially when using long descriptive strings like you did);
when importing more than one element from a module, it's usually better to group them instead of using single line imports: it makes the code tidier and easier to read and inspect: from PyQt5.QtWidgets import (QApplication, QMainWindow, QPushButton, QVBoxLayout, QWidget, QFileDialog)

Python - How to keep a QComboBox's QLineEdit from adding new items

Whenever you add a basic QLineEdit to a QComboBox, if you type anything into the QComboBox and press [Enter], the QLineEdit text will get added to the QComboBox.
Just to be clear, I still want to have the ability to manage the QComboBox items (add, remove, etc) like normal. In this case, only QLineEdit is not allowed to add new items.
I'd very much prefer a solution that did not require subclassing a built-in QLineEdit/QComboBox
Does anyone know how to do this?
import functools
import sys
# Use PySide/PyQt. Doesn't matter
from Qt import QtWidgets
def print_items(combo_box):
print([combo_box.itemText(index) for index in range(combo_box.count())])
def main():
app = QtWidgets.QApplication([])
window = QtWidgets.QComboBox()
line_edit = QtWidgets.QLineEdit()
line_edit.editingFinished.connect(functools.partial(print_items, window))
window.setLineEdit(line_edit)
window.show()
sys.exit(app.exec_())
# start writing in the QLineEdit and press [Enter].
# The item is now in the QComboBox and print in the terminal
if __name__ == '__main__':
main()

Remove top level QMenu from QMenubar programmatically

I am working on a Python project that uses Qt Designer to build interface. when working on building a plugin capability, I was able to allow dynamic loading of user plugins and create a new QMenu item to add to the main menubar. The problem is that there seems to be no way of removing that top level QMenu once it is added to the main menubar. I researched/searched quite a bit on this topic and it seems that every solution related to this topic is for removing sub-menu items from a QMenu via removing its actions, not for removing that dynamically-added QMenu itself. I hope someone would point out this to be a simple thing, and provide a code snippet to demo how this is done.

Achayan's solution above crashes on python2 qt4 (Windows) for the deletion
Better way for it is to to use the clear function.
Adding to the solution above,
def removeMenu():
self.main_menu.clear()

Hope this will give you idea for what you upto. And I took some part from another post, which is same qmenu thing
import sys
# This is bad, but Iam lazy
from PyQt4.QtCore import *
from PyQt4.QtGui import *
class MyWindow(QMainWindow):
def __init__(self):
super(MyWindow, self).__init__()
self.main_menu = self.menuBar()
widget = QWidget()
self.menuList = []
layout2 = QVBoxLayout(widget)
self.menuButton = QPushButton("Add Menu")
self.menuRmButton = QPushButton("Remove Menu")
layout2.addWidget(self.menuButton)
layout2.addWidget(self.menuRmButton)
self.menuButton.clicked.connect(self.create_menu)
self.menuRmButton.clicked.connect(self.removeMenu)
self.setCentralWidget(widget)
def create_menu(self):
menu2 = self.main_menu.addMenu('Menu 1')
self.menuList.append(menu2)
Action1=QAction('Menu 1 0',self)
Action1.triggered.connect(self.action_1)
menu2.addAction(Action1)
Action2=QAction('Menu 1 1',self)
Action2.triggered.connect(self.action_2)
menu2.addAction(Action2)
def removeMenu(self):
if self.menuList:
for eachMenu in self.menuList:
menuAct = eachMenu.menuAction()
self.main_menu.removeAction(menuAct)
# just for safe side
menuAct.deleteLater()
eachMenu.deleteLater()
def action_1(self):
print('Menu 1 0')
def action_2(self):
print('Menu 1 1')
if __name__ == '__main__':
app=QApplication(sys.argv)
new=MyWindow()
new.show()
app.exec_()

Use QAction without adding to menu (or toolbar)

I'm trying to develop an application with a very modular approach to commands and thought it would be nice, sind I'm using pyqt, to use QAction's to bind shortcuts to the commands.
However, it seems that actions shortcuts only works when the action is visible in a menu or toolbar. Does anyone know a way to get this action to work without it being visible?
Below some example code that shows what I'm trying.
Thanks,
André
from PyQt4 import *
from PyQt4.QtCore import *
from PyQt4.QtGui import *
import sys
class TesteMW(QMainWindow):
def __init__(self, *args):
QMainWindow.__init__(self, *args)
self.create_action()
def create_action(self):
self.na = QAction(self)
self.na.setText('Teste')
self.na.setShortcut('Ctrl+W')
self.connect(self.na, SIGNAL('triggered()'), self.action_callback)
# uncomment the next line for the action to work
# self.menuBar().addMenu("Teste").addAction(self.na)
def action_callback(self):
print 'action called!'
app = QApplication(sys.argv)
mw = TesteMW()
mw.show()
app.exec_()

You need to add your action to a widget before it will be processed. From the QT documentation for QAction:
Actions are added to widgets using
QWidget::addAction() or
QGraphicsWidget::addAction(). Note
that an action must be added to a
widget before it can be used; this is
also true when the shortcut should be
global (i.e., Qt::ApplicationShortcut
as Qt::ShortcutContext).
This does not mean that they will be visible as a menu item or whatever - just that they will be processes as part of the widgets event loop.