最小化QMainWindow时使模式QDialog最小化(使用PyQt 5)

from PyQt5.QtWidgets import QMainWindow, QPushButton, QDialog, QApplication

class MainWindow(QMainWindow):
    def __init__(self):
        super().__init__()
        self.setWindowTitle("Main Window")
        
        self.button = QPushButton("Open Dialog", self)
        self.button.clicked.connect(self.open_dialog)
        self.setCentralWidget(self.button)
        
    def open_dialog(self):
        dialog = CustomDialog(self)
        dialog.setModal(True)
        dialog.show()

from PyQt5.QtWidgets import QDialog, QVBoxLayout, QLabel, QApplication

class CustomDialog(QDialog):
    def __init__(self, parent=None):
        super().__init__(parent)
        self.setWindowTitle("Custom Dialog")
        
        layout = QVBoxLayout()
        label = QLabel("This is a custom dialog.", self)
        layout.addWidget(label)
        self.setLayout(layout)
        
    def closeEvent(self, event):
        event.ignore()
        self.parent().showMinimized()
        self.hide()

import sys

if __name__ == "__main__":
    app = QApplication(sys.argv)
    window = MainWindow()
    window.show()
    sys.exit(app.exec_())