E6 - dialogs and alerts

dialogs

GUI components that allow one to communicate with the user

handled by the QDialog class

import sys

from PyQt6.QtWidgets import QApplication, QMainWindow, QPushButton, QDialog, QVBoxLayout


class MainWindow(QMainWindow):
    def __init__(self):
        super().__init__()

        self.setWindowTitle("My App")
        self.setFixedSize(400, 300)

        button = QPushButton("Open dialog!")
        button.clicked.connect(self.button_clicked)
        self.setCentralWidget(button)

    def button_clicked(self, s):
        print("click", s)

        dialog = QDialog()
        dialog.setWindowTitle("Hello!")
        dialog.setFixedSize(200, 100)
        dialog.exec()


app = QApplication(sys.argv)
window = MainWindow()
window.show()
app.exec()

Note

using .exec() to start the dialog starts a new event loop, which blocks the application execution

class CustomDialog(QDialog):
    def __init__(self):
        super().__init__()

        self.setWindowTitle("Custom Dialog")
        self.setFixedSize(200, 100)

        QBtn = (
            QDialogButtonBox.StandardButton.Ok | 
            QDialogButtonBox.StandardButton.Cancel
        )

        self.buttonBox = QDialogButtonBox(QBtn)
        self.buttonBox.accepted.connect(self.accept)
        self.buttonBox.rejected.connect(self.reject)

        layout = QVBoxLayout()
        message = QLabel("Something happened, is that OK?")
        layout.addWidget(message)
        layout.addWidget(self.buttonBox)
        self.setLayout(layout)


class MainWindow(QMainWindow):

    # ... add the following method after the __init__

    def button_clicked(self, s):
        print("click", s)

        dlg = CustomDialog()
        if dlg.exec():
            print("Success!")
        else:
            print("Cancel!")