如何在动画过程中调整小部件的大小？

Question

我有这个代码

import sys
from PyQt5 import QtWidgets, QtGui, QtCore


class Content_wid(QtWidgets.QWidget):
    def __init__(self, conect, parent=None):
        super(Content_wid, self).__init__(parent)
        self.content = conect
        lay = QtWidgets.QVBoxLayout(self)
        lay.setContentsMargins(0, 0, 0, 0)

        self.radio = QtWidgets.QRadioButton()
        lay.addWidget(self.radio)

        self.animation = QtCore.QVariantAnimation()
        self.animation.setDuration(1000)
        self.animation.valueChanged.connect(self.on_value_changed)
        self.animation.setStartValue(self.content.area.sizeHint().height())
        self.animation.setEndValue(0)

    @QtCore.pyqtSlot("QVariant")
    def on_value_changed(self, val):
        self.content.area.setMaximumHeight(val)
        print(self.content.geometry())

    def swap_values(self):
        self.animation.blockSignals(True)
        start_value = self.animation.startValue()
        end_value = self.animation.endValue()
        self.animation.setStartValue(end_value)
        self.animation.setEndValue(start_value)
        self.animation.blockSignals(False)


class Menu(QtWidgets.QWidget):
    def __init__(self, parent=None):
        super(Menu, self).__init__(parent)
        lay = QtWidgets.QVBoxLayout(self)
        lay.setContentsMargins(0, 0, 0, 0)
        lay.setSpacing(0)

        self.group_buttons = QtWidgets.QButtonGroup(self, exclusive=True)
        self.group_animation = QtCore.QSequentialAnimationGroup(self)

        for x in range(3):
            self.area = QtWidgets.QScrollArea(self)
            self.area.setVerticalScrollBarPolicy(QtCore.Qt.ScrollBarAlwaysOff)
            self.area.setHorizontalScrollBarPolicy(QtCore.Qt.ScrollBarAlwaysOff)
            self.area.setStyleSheet('background:yellow;border:none;')
            self.area.setWidgetResizable(True)

            self.content = QtWidgets.QWidget()
            self.content.setStyleSheet('background:red')
            self.area.setWidget(self.content)

            lay_content = QtWidgets.QVBoxLayout(self.content)
            lay_content.setContentsMargins(0, 0, 0, 0)
            label = QtWidgets.QLabel(self.content)
            label.setText('test')
            label.setStyleSheet('background:green;padding:20')
            lay_content.addWidget(label)

            button = Content_wid(self)
            setattr(self, "but_{}".format(x), button)  # 1self 2name 3object
            self.group_buttons.addButton(button.radio, x)

            self.area.setMaximumHeight(0)

            wid_but = QtWidgets.QWidget()
            wid_but.setStyleSheet('background:black;')
            lay_wid_but = QtWidgets.QHBoxLayout(wid_but)
            lay_wid_but.setContentsMargins(0, 0, 0, 0)
            si = QtWidgets.QSpacerItem(0, 0, QtWidgets.QSizePolicy.Expanding, QtWidgets.QSizePolicy.Minimum)
            lay_wid_but.addWidget(button)
            lay_wid_but.addItem(si)
            lay.addWidget(wid_but)
            lay.addWidget(self.area)

        # margin down
        vs = QtWidgets.QSpacerItem(0, 0, QtWidgets.QSizePolicy.Minimum, QtWidgets.QSizePolicy.Expanding)
        lay.addItem(vs)

        self.group_buttons.buttonToggled.connect(self.on_button_toggled)
        self.last_widget = None

    @QtCore.pyqtSlot(QtWidgets.QAbstractButton, bool)
    def on_button_toggled(self, button, state):
        if state:
            wid = button.parent()
            if self.group_animation.animationCount() > 0:
                self.group_animation.takeAnimation(0)
            if isinstance(self.last_widget, Content_wid):
                # Invert
                self.last_widget.swap_values()
                self.group_animation.addAnimation(self.last_widget.animation)
            # Invert
            wid.swap_values()
            self.group_animation.addAnimation(wid.animation)
            self.group_animation.start()
            self.last_widget = wid


class Test(QtWidgets.QWidget):
    def __init__(self):
        super().__init__()
        self.resize(500, 500)
        lay = QtWidgets.QVBoxLayout(self)

        icon_wid_1 = Menu()

        lay.addWidget(icon_wid_1)

        parent_wid = QtWidgets.QWidget(self)
        parent_wid.setStyleSheet("background:red")
        parent_lay = QtWidgets.QVBoxLayout(parent_wid)

        icon_wid_3 = Menu(self)
        parent_wid.move(300, 300)
        parent_lay.addWidget(icon_wid_3)

        icon_wid_2 = Menu(self)
        icon_wid_2.move(100, 300)
        icon_wid_2.resize(50, 60)

if __name__ == '__main__':
    app = QtWidgets.QApplication(sys.argv)
    w = Test()
    w.show()
    sys.exit(app.exec_())

我希望Menu()小部件在动画过程中改变其大小，既处于自由位置又位于布局内部。我想在动画过程中获得Menu()的几何形状。如果Menu()超出了必要，那么一切都很好，但是如果少于 var group: FormGroup = new FormGroup({ ... services: new FormGroup({ service1:new FormControl(), service2:new FormControl(), service3:new FormControl(), otherServices:new FormControl() }) }); ，则会出现问题

我该如何解决这个问题？