import sys from PyQt5.QtWidgets import QMainWindow, QPushButton, QApplication from dialogs_2a import CustomDialog class MainWindow(QMainWindow): def __init__(self): super().__init__() self.setWindowTitle("My First Window") button = QPushButton("Press me for a dialog!") button.clicked.connect(self.button_clicked) self.setCentralWidget(button) def button_clicked(self, is_checked): print("click", is_checked) dlg = CustomDialog(self) if dlg.exec_(): print("Success!") else: print("Cancel!") app = QApplication(sys.argv) window = MainWindow() window.show() sys.exit(app.exec_())