Python Qt如何从QMainWindow打开弹出的QDialog

Question

I'm working on a project where I have a Database linked with a Python interface (I'm using Qt Designer for the design). I want to have a delete button from my main window ( QMainWindow ) where, when I'm pressing it, it opens a pop up ( QDialog ) which says

Are you sure you want to delete this item?

But I have no idea how to do it.

Thanks for you help!

Answer 1

def button_click():
    dialog = QtGui.QMessageBox.information(self, 'Delete?', 'Are you sure you want to delete this item?', buttons = QtGui.QMessageBox.Ok|QtGui.QMessageBox.Cancel)

Bind this function to the button click event.

Answer 2

Let's say your Qt Designer ui has a main window called "MainWindow" and a button called "buttonDelete".

The first step is to set up your main window class and connect the button's clicked signal to a handler:

from PyQt4 import QtCore, QtGui
from mainwindow_ui import Ui_MainWindow

class MainWindow(QtGui.QMainWindow, Ui_MainWindow):
    def __init__(self):
        QtGui.QMainWindow.__init__(self)
        self.setupUi(self)
        self.buttonDelete.clicked.connect(self.handleButtonDelete)

Next you need to add a method to the MainWindow class that handles the signal and opens the dialog:

    def handleButtonDelete(self):
        answer = QtGui.QMessageBox.question(
            self, 'Delete Item', 'Are you sure you want to delete this item?',
            QtGui.QMessageBox.Yes | QtGui.QMessageBox.No |
            QtGui.QMessageBox.Cancel,
            QtGui.QMessageBox.No)
        if answer == QtGui.QMessageBox.Yes:
            # code to delete the item
            print('Yes')
        elif answer == QtGui.QMessageBox.No:
            # code to carry on without deleting
            print('No')
        else:
            # code to abort the whole operation
            print('Cancel')

This uses one of the built-in QMessageBox functions to create the dialog. The first three arguments set the parent, title and text. The next two arguments set the group of buttons that are shown, plus the default button (the one that is initially highlighted). If you want to use different buttons, the available ones can be found here .

To complete the example, you just need some code to start the application and show the window:

if __name__ == '__main__':

    import sys
    app = QtGui.QApplication(sys.argv)
    window = MainWindow()
    window.show()
    sys.exit(app.exec_())

Answer 3

I got the same error for qt5.6

TypeError: question(QWidget, str, str, buttons: Union[QMessageBox.StandardButtons, QMessageBox.StandardButton] = QMessageBox.StandardButtons(QMessageBox.Yes|QMessageBox.No), defaultButton: QMessageBox.StandardButton = QMessageBox.NoButton): argument 1 has unexpected type 'Ui_MainWindow'

So I changed self to None in the following code, and it works.

def handleButtonDelete(self):
    answer = QtGui.QMessageBox.question(
        None, 'Delete Item', 'Are you sure you want to delete this item?',
        QtGui.QMessageBox.Yes | QtGui.QMessageBox.No |
        QtGui.QMessageBox.Cancel,
        QtGui.QMessageBox.No)
    if answer == QtGui.QMessageBox.Yes:
        # code to delete the item
        print('Yes')
    elif answer == QtGui.QMessageBox.No:
        # code to carry on without deleting
        print('No')
    else:
        # code to abort the whole operation
        print('Cancel')