#ifndef MAINWINDOW_H

 #define MAINWINDOW_H

 #include <QMainWindow>

 namespace Ui {

 class MainWindow;

 }

 class MainWindow : public QMainWindow

 {

     Q_OBJECT

 public:

     explicit MainWindow(QWidget *parent = );

     ~MainWindow();

 protected:

     void paintEvent(QPaintEvent *event);

     void mousePressEvent(QMouseEvent *event);

     void mouseMoveEvent(QMouseEvent *event);

     void mouseReleaseEvent(QMouseEvent *event);

 private:

     Ui::MainWindow *ui;

     QPoint m_pos;

     bool m_drag;

 };

 #endif // MAINWINDOW_H

 #include "mainwindow.h"

 #include "ui_mainwindow.h"

 #include <QPainter>

 #include <QBitmap>

 #include <QMouseEvent>

 MainWindow::MainWindow(QWidget *parent)

     : QMainWindow(parent),

       ui(new Ui::MainWindow)

 {

     ui->setupUi(this);

     ui->menuBar->close();

     ui->mainToolBar->close();

     ui->statusBar->close();

     setFixedSize(, );

     setWindowFlags(Qt::FramelessWindowHint);

     m_drag = false;

 }

 MainWindow::~MainWindow()

 {

     delete ui;

 }

 void MainWindow::paintEvent(QPaintEvent *event)

 {

     Q_UNUSED(event);

     QBitmap bitmap(this->size());

     QPainter painter(&bitmap);

     painter.fillRect(this->rect(), Qt::white);

     painter.setBrush(QColor(, , ));

     painter.setRenderHint(QPainter::Antialiasing);

     painter.setPen(QPen(Qt::blue, , Qt::SolidLine, Qt::RoundCap, Qt::RoundJoin));

     painter.drawRoundedRect(this->rect(), , );

     this->setMask(bitmap);

 }

 void MainWindow::mousePressEvent(QMouseEvent *event)

 {

     if (Qt::LeftButton == event->button()) {

         m_drag = true;

         m_pos = event->pos();

     }

 }

 void MainWindow::mouseMoveEvent(QMouseEvent *event)

 {

     Q_UNUSED(event);

     if (m_drag) {

         this->move(event->globalPos() - m_pos);

     }

 }

 void MainWindow::mouseReleaseEvent(QMouseEvent *event)

 {

     Q_UNUSED(event);

     m_drag = false;

 }