删除QCombobox可在窗口面板中显示所有数据，以便用户一次选择多个值

from PyQt5.QtWidgets import QApplication, QMainWindow, QComboBox, QListWidget, QVBoxLayout, QWidget

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

        self.combobox = QComboBox()
        self.listwidget = QListWidget()

        self.layout = QVBoxLayout()
        self.layout.addWidget(self.combobox)
        self.layout.addWidget(self.listwidget)

        self.central_widget = QWidget()
        self.central_widget.setLayout(self.layout)
        self.setCentralWidget(self.central_widget)

        self.combobox.addItem("Option 1")
        self.combobox.addItem("Option 2")
        self.combobox.addItem("Option 3")

        self.combobox.currentIndexChanged.connect(self.updateListWidget)

    def updateListWidget(self):
        self.listwidget.clear()
        for index in range(self.combobox.count()):
            item = self.combobox.itemText(index)
            self.listwidget.addItem(item)

if __name__ == "__main__":
    app = QApplication([])
    window = MainWindow()
    window.show()
    app.exec_()