20200519-01 QCustomPlot 关于标签拖动

谁践踏了优雅 2023-02-09 14:22 7阅读 0赞

# 一、前言： #

### 推荐阅读内容 ###

[https://www.cnblogs.com/swarmbees/p/6058263.html][https_www.cnblogs.com_swarmbees_p_6058263.html]

[https://www.cnblogs.com/xiongxuanwen/p/10102301.html][https_www.cnblogs.com_xiongxuanwen_p_10102301.html]

以及官方文档

# 二、正文 #

//新建一个标签
    
        m_label = new QCPItemText(m_plot);
        m_label->setClipToAxisRect(false);
        m_label->setPadding(QMargins(5, 5, 5, 5));
        m_label->setBrush(QBrush(Qt::NoBrush));
        m_label->setPen(QPen(QColor(Qt::red)));
        m_label->setFont(QFont("Arial", 8));
        m_label->setColor(Qt::black);
        m_label->setText("Test");
        m_label->setPositionAlignment(Qt::AlignLeft | Qt::AlignVCenter);
        m_label->setSelectedBrush(QBrush(Qt::green));
        //使能可选中
        m_label->setSelectable(true);
    
    
    //使能可选中，这里 QCP::iSelectItems 可以令像 Text/Line 这类控件能够被选中
        m_customplot->setInteractions(QCP::iSelectItems);
    
    //选中之后可以这个函数获取选中项
        m_customplot->selectedItems();
    
    //重新实例化鼠标事件
    void QCustomLine::mousePressEvent(QMouseEvent *event)
    {
        QCustomPlot::mousePressEvent(event);
    
        //默认设置同时只能选中一个，所以选取第一个对象
        if (m_customplot->selectedItems().isEmpty())
            return;
        temp_selected = dynamic_cast<QCPItemText*>(m_customplot->
                        selectedItems().value(0);
    }
    
    void QCustomLine::mouseMoveEvent(QMouseEvent *event)
    {
        routeMouseEvents(event);
        // 选中时候移动
        if (temp_selected) {
    
            temp_selected->setCoords(m_customplot->xAxis->pixelToCoord(event->x()),
                                     m_customplot->yAxis->pixelToCoord(event->y()));
            m_customplot->replot();
        }
    }
    
    void QCustomLine::mouseReleaseEvent(QMouseEvent *event)
    {
        routeMouseEvents(event);
    
        temp_selected = nullptr;
        qDebug() << "----released!";
    }

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzI0ODkwOTUz_size_16_color_FFFFFF_t_70][]

[https_www.cnblogs.com_swarmbees_p_6058263.html]: https://www.cnblogs.com/swarmbees/p/6058263.html
[https_www.cnblogs.com_xiongxuanwen_p_10102301.html]: https://www.cnblogs.com/xiongxuanwen/p/10102301.html
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzI0ODkwOTUz_size_16_color_FFFFFF_t_70]: https://img-blog.csdnimg.cn/20200519150607214.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzI0ODkwOTUz,size_16,color_FFFFFF,t_70