Pyqt диалоговое окно ошибка

Assuming you are in a QWidget from which you want to display an error message, you can simply use QMessageBox.critical(self, "Title", "Message"), replace self by another (main widget for example) if you are not is a QWidget class.

Edit: even if you are not in a QWidget (or don’t want to inherit from it), you can just use None as parent with for instance QMessageBox.critical(None, "Title", "Message").

Edit, here is an example of how to use it:

# -*-coding:utf-8 -*

from PyQt5.QtWidgets import QApplication, QMessageBox
import sys

# In this example, success is False by default, and
#  - If you press Cancel, it will ends with False,
#  - If you press Retry until i = 3, it will end with True


expectedVal = 3


def MyFunction(val: int) -> bool:
    return val == expectedVal


app = QApplication(sys.argv)
i = 1
success = MyFunction(i)
while not success:
    # Popup with several buttons, manage below depending on choice
    choice = QMessageBox.critical(None,
                                  "Error",
                                  "i ({}) is not expected val ({})".format(i, expectedVal),
                                  QMessageBox.Retry | QMessageBox.Cancel)
    if choice == QMessageBox.Retry:
        i += 1
        print("Retry with i = {}".format(i))
        success = MyFunction(i)
    else:
        print("Cancel")
        break

if success:
    # Standard popup with only OK button
    QMessageBox.information(None, "Result", "Success is {}".format(success))
else:
    # Standard popup with only OK button
    QMessageBox.critical(None, "Result", "Success is {}".format(success))

In this article, we will discuss the Message Box Widget of the PyQT5 module. It is used to display the message boxes. PyQt5 is a library used to create GUI using the Qt GUI framework. Qt is originally written in C++ but can be used in Python. The latest version of PyQt5 can be installed using the command:

pip install PyQt5

What is a Message Box?

Message Boxes are usually used for declaring a small piece of information to the user. It gives users a pop-up box, that cannot be missed, to avoid important errors and information being missed by the users and in some cases, the user cannot continue without acknowledging the message box.

Based on the applications there are four types of message boxes. The following is the syntax for creating a message box. For any of the boxes, instantiation needs to be done.

Syntax:

msg_box_name = QMessageBox() 

Now according to the requirement an appropriate message box is created.

Types of Message Box

Information Message Box

This type of message box is used when related information needs to be passed to the user.

Syntax:

msg_box_name.setIcon(QMessageBox.Information) 

Question Message Box

This message box is used to get an answer from a user regarding some activity or action to be performed.

Syntax:

msg_box_name.setIcon(QMessageBox.Question)

Warning Message Box

This triggers a warning regarding the action the user is about to perform.

Syntax:

msg_box_name.setIcon(QMessageBox.Warning)

Critical Message Box

This is often used for getting the user’s opinion for a critical action.  

Syntax:

msg_box_name.setIcon(QMessageBox.Critical)

Creating a simple Message Box using PyQt5

Now to create a program that produces a message box first import all the required modules, and create a widget with four buttons, on clicking any of these a message box will be generated.  

Now for each button associate a message box that pops when the respective button is clicked. For this first, instantiate a message box and add a required icon. Now set appropriate attributes for the pop that will be generated. Also, add buttons to deal with standard mechanisms.

Given below is the complete implementation.

Program:

Output

In this article, we will discuss the Message Box Widget of the PyQT5 module. It is used to display the message boxes. PyQt5 is a library used to create GUI using the Qt GUI framework. Qt is originally written in C++ but can be used in Python. The latest version of PyQt5 can be installed using the command:

pip install PyQt5

What is a Message Box?

Message Boxes are usually used for declaring a small piece of information to the user. It gives users a pop-up box, that cannot be missed, to avoid important errors and information being missed by the users and in some cases, the user cannot continue without acknowledging the message box.

Based on the applications there are four types of message boxes. The following is the syntax for creating a message box. For any of the boxes, instantiation needs to be done.

Syntax:

msg_box_name = QMessageBox() 

Now according to the requirement an appropriate message box is created.

Types of Message Box

Information Message Box

This type of message box is used when related information needs to be passed to the user.

Syntax:

msg_box_name.setIcon(QMessageBox.Information) 

Question Message Box

This message box is used to get an answer from a user regarding some activity or action to be performed.

Syntax:

msg_box_name.setIcon(QMessageBox.Question)

Warning Message Box

This triggers a warning regarding the action the user is about to perform.

Syntax:

msg_box_name.setIcon(QMessageBox.Warning)

Critical Message Box

This is often used for getting the user’s opinion for a critical action.  

Syntax:

msg_box_name.setIcon(QMessageBox.Critical)

Creating a simple Message Box using PyQt5

Now to create a program that produces a message box first import all the required modules, and create a widget with four buttons, on clicking any of these a message box will be generated.  

Now for each button associate a message box that pops when the respective button is clicked. For this first, instantiate a message box and add a required icon. Now set appropriate attributes for the pop that will be generated. Also, add buttons to deal with standard mechanisms.

Given below is the complete implementation.

Program:

Output

Код файла Python:

# -*- coding: utf-8 -*-


import sys
from PyQt5 import QtWidgets

class MessageBox(QtWidgets.QWidget):# Унаследовано от родительского класса QtWidgets.QWidget
    def __init__(self,parent = None):#parent = None означает, что этот QWidget принадлежит самому верхнему окну, то есть MainWindows.
        QtWidgets.QWidget.__init__(self)# Из-за отношения наследования для инициализации родительского класса
# Инициализировать родительский класс через super, функция __init __ () не имеет self, если это непосредственно QtWidgets.QWidget .__ init __ (self), в скобках указано self
        self.setGeometry(300, 300, 1000,1000)  Метод # setGeometry () выполняет две функции: устанавливает положение окна на экране и устанавливает размер самого окна. Его первые два параметра - это координаты x и y окна на экране. Последние два параметра - это ширина и высота самого окна.
        self.setWindowTitle(u'окно')  # Задайте заголовок формы, эта строка не обязательна.
        self.button = QtWidgets.QPushButton(u'контрольная работа', self)  # Создайте кнопку для отображения слова "тест"
        self.button.move(300,300)
        self.button.clicked.connect(self.show_message)  # Сигнальный слот

    def show_message(self):
        QtWidgets.QMessageBox.critical(self, "ошибка", «Системная ошибка, выключите и перезапустите»)
# Содержание должно быть длинным, слишком короткое приведет к неполному отображению заголовка!
app=QtWidgets.QApplication(sys.argv)
window=MessageBox()
window.show()
sys.exit(app.exec_())

Результаты приведены ниже:

5 ответов

error_dialog = QtWidgets.QErrorMessage()
error_dialog.showMessage('Oh no!')

import PyQt5
from PyQt5 import QtWidgets

app = QtWidgets.QApplication([])

error_dialog = QtWidgets.QErrorMessage()
error_dialog.showMessage('Oh no!')

app.exec_()

def my_exception_hook(exctype, value, traceback):
    # Print the error and traceback
    print(exctype, value, traceback)
    # Call the normal Exception hook after
    sys._excepthook(exctype, value, traceback)
    sys.exit(1)

# Back up the reference to the exceptionhook
sys._excepthook = sys.excepthook

# Set the exception hook to our wrapping function
sys.excepthook = my_exception_hook

msg = QMessageBox()
msg.setIcon(QMessageBox.Critical)
msg.setText("Error")
msg.setInformativeText(e)
msg.setWindowTitle("Error")

msg = QMessageBox()
msg.setIcon(QMessageBox.Critical)
msg.setText("Error")
msg.setInformativeText('More information')
msg.setWindowTitle("Error")
msg.exec_()

from PyQt5.QtWidgets import QMessageBox

def clickMethod(self):
    QMessageBox.about(self, "Title", "Message")

This PyQt5 Tutorial will show you how to create message boxes/popup windows using pyqt. We will use the QMessageBox class to accomplish this.

Creating a Basic GUI

I’ve started this tutorial by creating a very minimal GUI that contains one button. This way we can use the button press to trigger a popup/mesagebox.

This is what my GUI looks like:

Importing QMessageBox

To make our lives a little easier we will start by importing the QMessageBox class. This way each time we want to reference it we can use it directly.

from PyQt5.QtWidgets import QMessageBox

Creating a MessageBox

Note: I’m placing the code seen below inside the method that is linked to my button press. This way when the button is clicked a messagebox will appear on the screen.

Everytime we create a new popup window we need to create a new instance of QMessageBox.

Then we can start changing some properties of the messagebox like the title and the text.

msg.setWindowTitle("Tutorial on PyQt5")

msg.setText("This is the main text!")

The method names are pretty intuitive so I’ll pass on explaining them.

We will add some more to our messagebox later but for now lets test it out. To actually see the messagebox when we run the code we need to add one last line to the end of our method:

x = msg.exec_()  # this will show our messagebox

And this is what we get when we click the button!

Adding an Icon

A nice feature that our message boxes have it the ability to add an icon!

msg.setIcon(QMessageBox.Critical)

List of Icons
— QMessageBox.Critical
— QMessageBox.Warning
— QMessageBox.Information
— QMessageBox.Question

Here’s what our messagebox looks like with the Critical icon.

Adding/Changing Buttons

Now it’s time to change the buttons that show up in our QMessageBox. To do this we need to first select from a list of buttons that we’d like.

List of Buttons
— QMessageBox.Ok
— QMessageBox.Open
— QMessageBox.Save
— QMessageBox.Cancel
— QMessageBox.Close
— QMessageBox.Yes
— QMessageBox.No
— QMessageBox.Abort
— QMessageBox.Retry
— QMessageBox.Ignore

We can add any combinations of these buttons to our message box by using the following:

msg.setStandardButtons(QMessageBox.Retry | QMessageBox.Ignore | QMessageBox.Cancel) # seperate buttons with "|"

We can also set the button that will be highlighted by default by using:

msg.setDefaultButton(QMessageBox.Ignore)  # setting default button to Cancel

Now our messagebox looks like this!

Getting Button Pressed

Now that we’ve learned how to add more than one button is probably important to determine which button the user is clicking.

To do this we need to create a new method/function that takes one argument. This argument will be the button widget that was clicked.

    def popup_clicked(self, i):
        print(i.text())  # will print out the text on the button clicked

No we can link our messagebox to trigger that method when any button is pressed.

msg.buttonClicked.connect(self.popup_clicked)

Now when we click a button on the messagebox it’s text will be printed out to the console.

Other Properties

A few other things we can add are listed below:

Informative Text
This is the text that shows below the main text.

msg.setInformativeText("informative text, ya!")

Detail Text
This will generate a new button that will allow us to expand the message box and view more details.

msg.setDetailedText("details")

Full Code

from PyQt5 import QtCore, QtGui, QtWidgets
from PyQt5.QtWidgets import QMessageBox

class Ui_MainWindow(object):
	...
	def show_popup(self):
		msg = QMessageBox()
		msg.setWindowTitle("Tutorial on PyQt5")
		msg.setText("This is the main text!")
		msg.setIcon(QMessageBox.Question)
		msg.setStandardButtons(QMessageBox.Cancel|QMessageBox.Retry|QMessageBox.Ignore|)
		msg.setDefaultButton(QMessageBox.Retry)
		msg.setInformativeText("informative text, ya!")

		msg.setDetailedText("details")

		msg.buttonClicked.connect(self.popup_button)

	def popup_button(self, i):
		print(i.text())