(1)pro檔案中加入

QT +=  gui

(2)h檔案的類中加入標頭檔案：

#include <QMouseEvent>

類中加入函式和變數宣告：

protected:
    void mouseMoveEvent(QMouseEvent* event);
    void mousePressEvent(QMouseEvent* event);
    void mouseReleaseEvent(QMouseEvent* event);
private:
    QPoint mLastMousePosition;
    bool mMoving;
 

(3)cpp檔案中加入滑鼠事件相關函式的定義

void MainWindow::mousePressEvent(QMouseEvent* event)
{
    if(event->button() == Qt::LeftButton)
    {
        mMoving = true;
        mLastMousePosition = event->globalPos();
    }
}
 
void MainWindow::mouseMoveEvent(QMouseEvent* event)
{
    if( event->buttons().testFlag(Qt::LeftButton) && mMoving)
    {
        this->move(this->pos() + (event->globalPos() - mLastMousePosition));
        mLastMousePosition = event->globalPos();
    }
}
 
void MainWindow::mouseReleaseEvent(QMouseEvent* event)
{
    if(event->button() == Qt::LeftButton)
    {
        mMoving = false;
    }
}
 

轉載自https://blog.csdn.net/qq_28093585/article/details/78483019