Widgets are not displayed - python

I'm currently doing a tutorial on how to create GUI apps from a book called "Modern PyQt" by Joshua Willman and I'm stuck right out of the gate:
I've copy pasted a basic code snippet from the book and tried to tweak it bit by bit instead of reading a bunch of text without any practical trial and error. I can display a window and adjust it's size and properties, but when I try to attach other widgets to the main window, they just don't show up.
Here's what I've got so far:
# First practical example from the book: Pomodoro time manager
import sys
from PyQt5.QtWidgets import QApplication, QWidget, QPushButton
from PyQt5.QtGui import QIcon
class Pomodoro(QWidget):
def __init__(self): # Create default constructor
super().__init__()
self.initializeUI()
def initializeUI(self):
"""Initialize the window and display its contents to the screen."""
self.setGeometry(int((SCREEN_WIDTH-WINDOW_WIDTH)/2),int((SCREEN_HEIGHT-WINDOW_HEIGHT)/2),WINDOW_WIDTH,WINDOW_HEIGHT) # x,y,w,h
self.setWindowTitle('Bortism')
# self.setWindowIcon(QIcon("Borticon.png"))
self.button1 = QPushButton()
self.button1.setText('Button')
self.show()
if __name__ == '__main__':
app = QApplication(sys.argv)
WINDOW_WIDTH, WINDOW_HEIGHT = 1000,600
SCREEN_X, SCREEN_Y, SCREEN_WIDTH, SCREEN_HEIGHT = app.desktop().screenGeometry().getRect()
window = Pomodoro()
sys.exit(app.exec_())

For a widget to be shown as part of another then the requirement is that the first is the child of the second. This can be done by passing the parent or by using a layout (which is also passed to it by the parent). So in your case you must change to:
self.button1 = QPushButton(self)

Related

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.

PyCharm giving cannot find reference and unexpected argument warnings when working with inherited classes from PyQt6 despite code working normally

I am trying to make a calculator app using PyQt6 and I wanted a QPushButton with fixed size to go into a grid layout. I was going to be using this button a lot so I created my own SquarePushButton class inheriting from QPushButton with an additional setMinimumSize and setMaximumSize already in the init function.
I simplified the code as much as possible while replicating the error which is why I am using a QGridLayout for just two widgets.
When I run it, the code works perfectly fine and as expected.
import sys
from PyQt6.QtCore import QSize
from PyQt6.QtWidgets import QWidget, QApplication, QPushButton, QLabel, QGridLayout
# class to have a button of fixed size
class SquarePushButton(QPushButton):
def __init__(self, text):
super().__init__()
self.setText(text)
self.setMinimumSize(QSize(50, 50))
self.setMaximumSize(QSize(50, 50))
# main window class
class MyWindow(QWidget):
def __init__(self):
super().__init__()
# create a text label
self.label = QLabel(self)
self.label.setText("Label")
# create a button
btn = SquarePushButton("Button")
btn.clicked.connect(self.buttonPressed)
# error: "Cannot find reference 'connect' in 'function'"
# add text label into layout
layout = QGridLayout()
layout.addWidget(self.label, 0, 0)
layout.addWidget(btn, 0, 1)
# sets the layout
self.setLayout(layout)
def buttonPressed(self):
self.label.setText("Pressed")
if __name__ == '__main__':
app = QApplication(sys.argv)
window = MyWindow()
window.show()
sys.exit(app.exec())
Here it gives me an error saying "Cannot find reference 'connect' in 'function'"
However if I change how the QWidgets are imported I get a new error at a completely different location, this time the error occurs during layout.addWidget, where it says "unexpected argument" for the last two arguments.
Keep in mind everything still works, its just PyCharm IDE getting mad at me.
import sys
from PyQt6.QtCore import QSize
from PyQt6.QtWidgets import *
# class to have a button of fixed size
class SquarePushButton(QPushButton):
def __init__(self, text):
super().__init__()
self.setText(text)
self.setMinimumSize(QSize(50, 50))
self.setMaximumSize(QSize(50, 50))
# main window class
class MyWindow(QWidget):
def __init__(self):
super().__init__()
# create a text label
self.label = QLabel(self)
self.label.setText("Label")
# create a button
btn = SquarePushButton("Button")
btn.clicked.connect(self.buttonPressed)
# add text label into layout
layout = QGridLayout()
layout.addWidget(self.label, 0, 0)
layout.addWidget(btn, 0, 1)
# error: "unexpected argument"
# sets the layout
self.setLayout(layout)
def buttonPressed(self):
self.label.setText("Pressed")
if __name__ == '__main__':
app = QApplication(sys.argv)
window = MyWindow()
window.show()
sys.exit(app.exec())
Note: It would be easiest to spot if you just copy and pasted the code into your PyCharm IDE because it highlights the supposed error.
I do not understand why there is an error there, everything seems to be working fine so is this a PyCharm bug, PyQt6 bug or am I just using inheritance incorrectly? I am quite new to Python still so sorry if this is really stupid.

How to make an image selectable using pixmap and Qlabel?

I am trying to show multiple images using Pyqt5. It would be nice to make the image selectable within the GUI so that the users can select and copy that image right away easily.
By "selectable", I meant the user can right click the image and then copy it and then potentially paste it to somewhere else outside of the GUI. Just like a normal image saved in a Word. User can select/copy an image in Word and then paste it to somewhere else.
I know for Text in Qlabel this can easily achieved by using self.my_label.setTextInteractionFlags(QtCore.Qt.TextSelectableByMouse). However, it seems for images there is no such method handling it. Is there any way I can work it out for images?
import sys
import PyQt5
from PyQt5.QtWidgets import (
QLabel,
QVBoxLayout,
QWidget
)
from PyQt5 import QtCore
from PyQt5.QtGui import QPixmap
from PyQt5.QtCore import QSize
class Display_Window(QWidget):
def __init__(self):
super().__init__()
self.setMinimumSize(QSize(980,700))
self.layout = QVBoxLayout(self)
self.label1 = QLabel(self)
self.pixmap = QPixmap(path_to_my_image)
self.pixmap = self.pixmap.scaled(900, 900, QtCore.Qt.KeepAspectRatio)
self.label1.setPixmap(self.pixmap)
self.label1.resize(self.pixmap.width(), self.pixmap.height())
# Run if Script
if __name__ == "__main__":
app = PyQt5.QtWidgets.QApplication(sys.argv)
MainWindow = Display_Window() # Initialize GUI
MainWindow.show() # Show Window
app.exec_()
You can subclass the label and create a menu whenever it has a valid pixmap, then use the system clipboard to copy it.
class CopiableLabel(QLabel):
def contextMenuEvent(self, event):
pixmap = self.pixmap()
if not pixmap.isNull():
menu = QMenu()
copyAction = menu.addAction('Copy image to clipboard')
if menu.exec_(event.globalPos()) == copyAction:
QApplication.clipboard().setPixmap(pixmap)
return
super().contextMenuEvent(event)
class Display_Window(QWidget):
def __init__(self):
super().__init__()
self.layout = QVBoxLayout(self)
self.label1 = CopiableLabel(self)
self.layout.addWidget(self.label1)
self.pixmap = QPixmap(path_to_my_image)
self.pixmap = self.pixmap.scaled(900, 900, Qt.KeepAspectRatio)
self.label1.setPixmap(self.pixmap)
Note that setting a pixmap on a QLabel automatically resizes it (unless it has the scaledContents property set to True.
You also should add the label to the layout, as I did in the above modifications.

How application structure should looks like?

I'm trying to create a small database app to keep all clients inside. I would like to write GUI using PyQt5. I have a problem with understanding how app structure should looks like.
I'd like to have a main class which starts the app and I want to seperate GUI, DB and Main classes in different files.
You can see my code snippets bellow. It don't work because some variables are not recognized and accually I don't understand why.
My thoughts:
1. Window, tab1 objects will be created in main class init function
2. When window, tab1 instances were created, the methods inside it's init will be called
3. I have window, tab1 objects and it's variables are available for themselves
window.gbT1Main.setLayout(T1LayMain) is not defined for TabNewClient class. Why ? How should I change my code to achieve above requirements? Please explain me how should I connect my classes :(
Window and TabNewClient class (window, tab1)
from PyQt5.QtWidgets import QApplication, QDialog, QTabWidget, QGroupBox, QVBoxLayout, QHBoxLayout, QLabel, QPushButton, QFormLayout, QLineEdit, QDateEdit, QTextEdit, QRadioButton, QGridLayout
import sys
import datetime
class Window(QDialog):
def __init__(self):
super().__init__()
self.InitWindow()
def InitWindow(self):
# create tab widget
self.tab = QTabWidget()
# create MainWindow groupbox
self.gbMainWindow = QGroupBox()
# TAB groupBoxes
self.gbT1Main = QGroupBox()
self.gbT2Main = QGroupBox("Main2")
self.gbT3Main = QGroupBox("Main3")
# Adding tabs
self.tab.addTab(self.gbT1Main, "Dodaj klienta")
self.tab.addTab(self.gbT2Main, "Wyszukaj")
self.tab.addTab(self.gbT3Main, "Statystki")
# Setting MainWindow title
self.setWindowTitle("MEDIKAP - gabinet medycyny pracy")
# Main Window Layout
self.layMainWindow = QHBoxLayout()
# Set MainWindow Layout
self.layMainWindow.addWidget(self.tab)
self.gbMainWindow.setLayout(self.layMainWindow)
# set MainWindow layout visible
self.setLayout(self.layMainWindow)
#show window
self.show()
class TabNewClient:
def __init__(self):
self.CreateTab1Layout()
def CreateTab1Layout(self):
self.gbAddClient = QGroupBox("Dane klienta")
self.gbRodzajBadania = QGroupBox("Podstawa prawna")
self.gbDane = QGroupBox()
self.gbComment = QGroupBox("Komentarz")
self.gbButtons = QGroupBox()
# TAB1 - layouts
T1LayMain = QVBoxLayout()
layDane = QHBoxLayout()
# TAB1
layDane.addWidget(self.gbAddClient)
layDane.addWidget(self.gbRodzajBadania)
self.gbDane.setLayout(layDane)
# TAB1 - set layout to Main
T1LayMain.addWidget(self.gbDane)
T1LayMain.addWidget(self.gbComment)
T1LayMain.addWidget(self.gbButtons)
window.gbT1Main.setLayout(T1LayMain)
Main class:
from PyQt5.QtWidgets import QApplication
import sys
from guiv3 import Window, TabNewClient
class Main:
def __init__(self):
window = Window()
tab1 = TabNewClient()
if __name__ == "__main__":
app = QApplication(sys.argv)
main = Main()
app.exec_()
error:
window.gbT1Main.setLayout(T1LayMain)
NameError: name 'window' is not defined
To answer the question of why you get an error about 'window' not being defined, I believe it's because there is no window variable in the TabNewClient class. It looks like you're attempting to refer to the window defined in Main, but that won't work since that variable isn't in the scope of the TabNewClient class. My guess is that you're going to run into the same issue with gbT1Main, since that is outside the scope of the TabNewClient class as well.
Edit: I think I understand what you're attempting here. You want the gbT1Main related tab in window to hold the layout from tab1. To do that, you will need to set window's layout in Main:
from PyQt5.QtWidgets import QApplication
import sys
from guiv3 import Window, TabNewClient
class Main:
def __init__(self):
window = Window()
tab1 = TabNewClient()
window.gbT1Main.setLayout(tab1.T1LayMain)
if __name__ == "__main__":
app = QApplication(sys.argv)
main = Main()
app.exec_()
That's most likely what you're looking for.
Important: this also requires that T1LayMain be an attribute of the TabNewClient class, so use self.T1LayMain inside that class for it to be accessible outside it.

How to resize a QColorDialog

Is it possible to resize a QColorDialog? I have been unable to get the window to resize appropriately. After the dialog is shown, it reverts to the default size.
An example:
import sys
from PyQt5.QtGui import *
from PyQt5.QtWidgets import *
from PyQt5.QtCore import *
class Window(QWidget):
def __init__(self):
super().__init__()
layout = QVBoxLayout()
push_Button = QPushButton()
layout.addWidget(push_Button)
push_Button.clicked.connect(self.button)
self.setLayout(layout)
def button(self):
color = QColorDialog(self)
color.resize(100,100)
print(color.size()) #Prints 100, 100
color.show()
print(color.size()) #Prints 551, 431
if __name__ == '__main__':
app = QApplication(sys.argv)
window = Window()
window.show()
sys.exit(app.exec_())
The QColorDialog has a fixed size, because it contains several custom widgets which aren't designed to be resizable. It is possble to override these constraints and allow for manual resizing like this:
color = QColorDialog(self)
color.setSizeGripEnabled(True)
color.layout().setSizeConstraint(QLayout.SetNoConstraint)
color.show()
However, as you will see, the layout quickly becomes messed up with even a little bit of resizing. I also found that beyond a certain point, the dialog will actually crash due to floating point exceptions. So I think you will either have to accept it as it is, or perhaps write your own color dialog.

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