Qt自定义主窗口的放大，缩小，关闭功能

//设置为无边框，自定义关闭，放大，缩小按钮
    this->setWindowFlags(Qt::FramelessWindowHint);
    //顶部按钮响应
    connect(ui.pBClose, &QPushButton::clicked, [=]() {close(); });
    connect(ui.pBMaxWindow, &QPushButton::clicked, [=]() 
    {    if (this->isMaximized())
        {
            this->showNormal();
        }
        else
        {
            this->showMaximized();
        }
    });
    connect(ui.pBMinWindow, &QPushButton::clicked, [=]() {this->showMinimized(); });

void AlgorithmConfig::mousePressEvent(QMouseEvent * event)
{
    //只能是鼠标左键移动和改变大小
    if (event->button() == Qt::LeftButton)
    {
        if (ui.widgetToolBar->underMouse())
        {
            m_leftMousePressed = true;
            //按下时鼠标左键时，窗口在屏幕中的坐标
            m_StartPoint = event->globalPos();
        }
    }


}

void AlgorithmConfig::mouseReleaseEvent(QMouseEvent * event)
{
    m_leftMousePressed = false;
}

void AlgorithmConfig::mouseDoubleClickEvent(QMouseEvent * event)
{
    if (ui.widgetToolBar->underMouse())
    {
        if (isMaximized())
        {
            showNormal();
        }
        else
        {
            showMaximized();
        }
    }
}