mainwindow 无菜单栏 可拖动，边界可扩大，动画浮现上边框

#ifndef ANIMATIONWIN_H
#define ANIMATIONWIN_H

#include

namespace Ui {
class animationWin;
}

class animationWin : public QWidget
{
Q_OBJECT

public:
explicit animationWin(QWidget *parent = nullptr);
~animationWin();

private:
Ui::animationWin *ui;
};

#endif // ANIMATIONWIN_H

#include “animationwin.h”
#include “ui_animationwin.h”
#include
#include

animationWin::animationWin(QWidget parent) :
QWidget(parent),
ui(new Ui::animationWin)
{
ui->setupUi(this);
QPropertyAnimation pAnimation = new QPropertyAnimation(this, “geometry”);

QDesktopWidget*  pDesktopWidget = QApplication::desktop();int  x = (pDesktopWidget->availableGeometry().width() - width()) / 2;int  y = (pDesktopWidget->availableGeometry().height() - height()) / 2;pAnimation->setDuration(1000);pAnimation->setStartValue(QRect(x, 0, width(), 0));pAnimation->setEndValue(QRect(x, 0, width(), height()));   //pAnimation->start(QAbstractAnimation::DeleteWhenStopped);

}

animationWin::~animationWin()
{
delete ui;
}

#ifndef MAINWINDOW_H
#define MAINWINDOW_H

#include
#include
#include “animationwin.h”

QT_BEGIN_NAMESPACE
namespace Ui { class MainWindow; }
QT_END_NAMESPACE

class MainWindow : public QMainWindow<