隐藏并显示包含所有微件的`QGridLayout`

from PyQt5.QtWidgets import QApplication, QWidget, QGridLayout, QPushButton, QLabel

class MyWindow(QWidget):
    def __init__(self):
        super().__init__()
        self.initUI()

    def initUI(self):
        self.layout = QGridLayout()
        self.setLayout(self.layout)

        # 添加一些小部件到布局中
        for i in range(3):
            for j in range(3):
                button = QPushButton(f'Button {i},{j}')
                self.layout.addWidget(button, i, j)

        # 添加一个按钮来切换所有小部件的可见性
        toggle_button = QPushButton('Toggle Visibility')
        toggle_button.clicked.connect(self.toggle_visibility)
        self.layout.addWidget(toggle_button, 3, 0, 1, 3)

    def toggle_visibility(self):
        for i in range(self.layout.count()):
            item = self.layout.itemAt(i)
            widget = item.widget()
            if widget is not None:
                widget.setVisible(not widget.isVisible())

app = QApplication([])
window = MyWindow()
window.show()
app.exec_()