Как вывести сообщение об ошибке pyqt5

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