运行QPropertyAnimation后QWiget的怪异行为

我正在两个小部件上运行下一个动画：

QParallelAnimationGroup* animGroup = new QParallelAnimationGroup;
for (int i = 0; i < 2; ++i) {
//widgets is an array of 2 QLabels
QPropertyAnimation* anim = new QPropertyAnimation(widgets[i], "geometry");
anim->setDuration(750);
anim->setStartValue(widgets[i]->geometry());
widgets[i]->setProperty("animating", true);
qDebug() << QString("Animation Start %1: ").arg(widgets[i]->objectName()) << widgets[i]->pos() << " g " << widgets[i]->geometry();
//
anim->setEndValue(widgets[!i]->geometry());
anim->setEasingCurve(QEasingCurve::OutBack);
animGroup->addAnimation(anim);
}
animGroup->start(QAbstractAnimation::DeleteWhenStopped);

到目前为止，动画可以按预期移动两个小部件，但只要我调整窗口大小，这些小部件就会自动移回原来的位置。包含这两个小部件的当前布局是QHBoxLayout，并且具有以下项目(相同顺序)：

QLabel0|QSpacerItem0|QToolTipButton |QSpacer Item1|QL标签1

动画之后，它们变成：

QLabel1|QSpacerItem0|QToolTipButton |QSpacer Item1|QL标签0

但每当我更改窗口的大小时，小部件上的位置就会重置为原始布局。我还没有从窗口中实现resizeEvent。

我使用的是带有Visual Studio | Qt Visual Studio Tools 2.3.1和Qt 12.0的Windows 10，构建时启用了msvc2017_64版本和c++17。

完整测试代码(新项目)：

SwapItemsTest.cpp

#include "SwapItemsTest.h"
#include <array>
#include <QHBoxLayout>
#include <QToolButton>
#include <QSpacerItem>
#include <QLabel>
#include <QDebug>
#include <QParallelAnimationGroup>
#include <QPropertyAnimation>
#include <QTimer>
SwapItemsTest::SwapItemsTest(QWidget *parent)
: QMainWindow(parent)
{
ui.setupUi(this);
auto layout = new QHBoxLayout;
auto toolButton = new QToolButton;
auto left = new QLabel("Left");
left->setFixedSize(50, size().height());
left->setFrameShape(QFrame::Box);
left->setFrameShadow(QFrame::Plain);
left->setLineWidth(2);
left->setAlignment(Qt::AlignCenter);
auto right = new QLabel("Right");
right->setFixedSize(50, size().height());
right->setAlignment(Qt::AlignCenter);
right->setFrameShape(QFrame::Box);
right->setFrameShadow(QFrame::Plain);
right->setLineWidth(2);
layout->addWidget(left);
layout->addSpacerItem(new QSpacerItem(40, 40));
layout->addWidget(toolButton);
layout->addSpacerItem(new QSpacerItem(40, 40));
layout->addWidget(right);
ui.centralWidget->setLayout(layout);
auto widgets = std::array{left, right};
connect(toolButton, &QToolButton::clicked, [widgets]() {
QParallelAnimationGroup* animGroup = new QParallelAnimationGroup;
for (int i = 0; i < 2; ++i) {
//widgets is an array of 2 QLabels
QPropertyAnimation* anim = new QPropertyAnimation(widgets[i], "geometry");
anim->setDuration(750);
anim->setStartValue(widgets[i]->geometry());
widgets[i]->setProperty("animating", true);
anim->setEndValue(widgets[!i]->geometry());
anim->setEasingCurve(QEasingCurve::OutBack);
animGroup->addAnimation(anim);
}
animGroup->start(QAbstractAnimation::DeleteWhenStopped); 
});

}

SwapItemsTest.h

#pragma once
#include <QtWidgets/QMainWindow>
#include "ui_SwapItemsTest.h"
class SwapItemsTest : public QMainWindow
{
Q_OBJECT
public:
SwapItemsTest(QWidget *parent = Q_NULLPTR);
private:
Ui::SwapItemsTestClass ui;
};