• 设置为无边框窗口

this->setWindowFlags(Qt::FramelessWindowHint); // 设置为无边框窗口

• 按下处理

void Borderless::mousePressEvent(QMouseEvent *event)
{
    if (event->button() == Qt::LeftButton) {
        mouseStartPosition = event->globalPos() - frameGeometry().topLeft();
        mouseDragging = true; // 开启拖动状态
    }
}

• 移动

void Borderless::mouseMoveEvent(QMouseEvent *event)
{
    if (mouseDragging) {
        // 移动窗口
        move(event->globalPos() - mouseStartPosition);
    }
}

• 松开

void Borderless::mouseReleaseEvent(QMouseEvent *event)
{
    if (event->button() == Qt::LeftButton) {
        mouseDragging = false; // 关闭拖动状态
    }
}

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