QtChart官方自带example（Callout）X轴坐标逆序后遇到的问题，求大神指点_qt callout

#include "GraphPage.h"
#include <QtGui/QResizeEvent>
#include <QtWidgets/QGraphicsScene>
#include <QtCharts/QChart>
#include <QtCharts/QLineSeries>
#include <QtCharts/QSplineSeries>
#include <QtWidgets/QGraphicsTextItem>
#include <QtGui/QMouseEvent>
 
#include <QDebug>
 
GraphPage::GraphPage(QChartView *parent)
    : QChartView(parent),
      poChart(0),
      poCallout(0)
{
    this->setDragMode(QChartView::NoDrag);
    this->setVerticalScrollBarPolicy(Qt::ScrollBarAlwaysOff);
    this->setHorizontalScrollBarPolicy(Qt::ScrollBarAlwaysOff);
 
    // chart
    poChart = new QChart;
    poChart->setMinimumSize(640, 480);
    poChart->setTitle("Hover the line to show callout. Click the line to make it stay");
    poChart->legend()->setAlignment(Qt::AlignRight);
    QLineSeries *poSeries = new QLineSeries;
 
    poSeries->setName("L1-100/D88-1(Ex)");
    poSeries->setPointsVisible(true);
    poSeries->append(1, 3);
    poSeries->append(2, 5);
    poSeries->append(3, 4.5);
    poSeries->append(4, 1);
    poSeries->append(5, 2);
    poSeries->append(6, 9);
 
    poChart->addSeries(poSeries);
 
    QSplineSeries *series2 = new QSplineSeries;
    series2->setPointsVisible(true);
    series2->setName("L1-101/D69-2(Ex)");
 
    series2->append(1, 1.4);
    series2->append(2, 3.5);
    series2->append(3, 2.5);
    series2->append(4, 4);
    series2->append(5, 2);
    series2->append(6, -6);
 
    poChart->addSeries(series2);
 
    QLogValueAxis *poAxisX = new QLogValueAxis;
    poAxisX->setLabelFormat("%g");
    poAxisX->setTitleText(QObject::tr("频率(Hz)"));
    poAxisX->setBase(10);
    poAxisX->setLabelsVisible(true);
    poAxisX->setLabelsAngle(26);
    poAxisX->setReverse(false);
 
    poChart->addAxis(poAxisX, Qt::AlignBottom);
 
    poSeries->attachAxis(poAxisX);
    series2->attachAxis(poAxisX);
 
    QValueAxis *poAxisY = new QValueAxis;
    poAxisY->setLabelFormat("%g");
    poAxisY->setTitleText(QObject::tr("电场值(\u03BCV)"));
 
    poChart->addAxis(poAxisY, Qt::AlignLeft);
 
    poSeries->attachAxis(poAxisY);
    series2->attachAxis(poAxisY);
 
    poChart->setAcceptHoverEvents(true);
 
    setRenderHint(QPainter::Antialiasing);
 
    this->setChart(poChart);
 
    connect(poSeries, SIGNAL(hovered(QPointF, bool)), this, SLOT(TooltipShow(QPointF,bool)));
 
    connect(series2, SIGNAL(hovered(QPointF, bool)), this, SLOT(TooltipShow(QPointF,bool)));
 
    this->MarkersConnect(poChart);
 
    this->setMouseTracking(true);
}
 
void GraphPage::TooltipShow(QPointF oPoint, bool bState)
{
    QLineSeries *poSeries = qobject_cast<QLineSeries *>(sender());
 
    QList<QPointF> aoPointF = poSeries->points();
 
    QList<qreal> arDst;
    for(int i = 0; i < aoPointF.count(); i++)
    {
        arDst.append( qAbs(aoPointF[i].x() - oPoint.x()) );
    }
    qreal rMin = arDst[0];
    for(int i = 1 ; i < arDst.count(); i++)
    {
        if(arDst[i]< rMin)
        {
            rMin = arDst[i];
        }
    }
 
 
    QPointF seriesPoint = aoPointF[arDst.indexOf(rMin)];
 
 
    if (poCallout == 0)
        poCallout = new Callout(poChart);
 
    if (bState)
    {
        qDebug()<<"rMin value:"<<rMin;
 
        qDebug()<<"index:"<<arDst.indexOf(rMin);
 
        poCallout->setText(QString("%1\n(%2Hz, %3\u03bcV)")
                           .arg(poSeries->name())
                           .arg(seriesPoint.x())
                           .arg(seriesPoint.y()));
        poCallout->setAnchor(poChart->mapToPosition(seriesPoint, poSeries));
        poCallout->setPos(poChart->mapToPosition(seriesPoint, poSeries) + QPoint(10, -50));
        poCallout->setZValue(11);
        poCallout->show();
    }
    else
    {
        poCallout->hide();
    }
}
 
void GraphPage::resizeEvent(QResizeEvent *event)
{
    if (scene())
    {
        this->scene()->setSceneRect(QRect(QPoint(0, 0), event->size()));
        poChart->resize(event->size());
 
    }
    QGraphicsView::resizeEvent(event);
}
 
/***************************************************
 * Connect legend
 */
void GraphPage::MarkersConnect(QChart *poChart)
{
    /* Connect all markers to handler */
    foreach (QLegendMarker* poLegendMarker, poChart->legend()->markers())
    {
        /* Disconnect possible existing connection to avoid multiple connections */
        disconnect(poLegendMarker, SIGNAL(clicked()), this, SLOT(HandleMarkerClicked()));
        connect(poLegendMarker, SIGNAL(clicked()), this, SLOT(HandleMarkerClicked()));
    }
}
 
/*******************************************************************************
 * Handle Marker Clicked
 */
void GraphPage::HandleMarkerClicked()
{
    QLegendMarker* poLegendMarker = qobject_cast<QLegendMarker*> (sender());
    Q_ASSERT(poLegendMarker);
 
    switch (poLegendMarker->type())
    {
    case QLegendMarker::LegendMarkerTypeXY:
    {
        /* Toggle visibility of Series */
        poLegendMarker->series()->setVisible(!poLegendMarker->series()->isVisible());
 
        /* Turn legend marker back to visible,
         * since hiding poSeries also hides the marker
         * and we don't want it to happen now. */
        poLegendMarker->setVisible(true);
 
        /* Dim the marker, if series is not visible */
        qreal alpha = 1.0;
 
        if (!poLegendMarker->series()->isVisible())
        {
            alpha = 0.5;
        }
 
        QColor oColor;
        QBrush oBrush = poLegendMarker->labelBrush();
        oColor = oBrush.color();
        oColor.setAlphaF(alpha);
        oBrush.setColor(oColor);
        poLegendMarker->setLabelBrush(oBrush);
 
        oBrush = poLegendMarker->brush();
        oColor = oBrush.color();
        oColor.setAlphaF(alpha);
        oBrush.setColor(oColor);
        poLegendMarker->setBrush(oBrush);
 
        QPen oPen = poLegendMarker->pen();
        oColor = oPen.color();
        oColor.setAlphaF(alpha);
        oPen.setColor(oColor);
        poLegendMarker->setPen(oPen);
 
        break;
    }
    default:
    {
        qDebug() << "Unknown poLegendMarker type";
        break;
    }
    }
}

/****************************************************************************
**
** Copyright (C) 2016 The Qt Company Ltd.
** Contact: https://www.qt.io/licensing/
**
** This file is part of the Qt Charts module of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:GPL$
** Commercial License Usage
** Licensees holding valid commercial Qt licenses may use this file in
** accordance with the commercial license agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and The Qt Company. For licensing terms
** and conditions see https://www.qt.io/terms-conditions. For further
** information use the contact form at https://www.qt.io/contact-us.
**
** GNU General Public License Usage
** Alternatively, this file may be used under the terms of the GNU
** General Public License version 3 or (at your option) any later version
** approved by the KDE Free Qt Foundation. The licenses are as published by
** the Free Software Foundation and appearing in the file LICENSE.GPL3
** included in the packaging of this file. Please review the following
** information to ensure the GNU General Public License requirements will
** be met: https://www.gnu.org/licenses/gpl-3.0.html.
**
** $QT_END_LICENSE$
**
****************************************************************************/
 
#include "Callout.h"
#include <QtGui/QPainter>
#include <QtGui/QFontMetrics>
#include <QtWidgets/QGraphicsSceneMouseEvent>
#include <QtGui/QMouseEvent>
 
Callout::Callout(QGraphicsItem * parent):
    QGraphicsItem(parent)
{
}
 
QRectF Callout::boundingRect() const
{
    QPointF anchor = mapFromParent(m_anchor);
    QRectF rect;
    rect.setLeft(qMin(m_rect.left(), anchor.x()));
    rect.setRight(qMax(m_rect.right(), anchor.x()));
    rect.setTop(qMin(m_rect.top(), anchor.y()));
    rect.setBottom(qMax(m_rect.bottom(), anchor.y()));
    return rect;
}
 
void Callout::paint(QPainter *painter, const QStyleOptionGraphicsItem *option, QWidget *widget)
{
    Q_UNUSED(option)
    Q_UNUSED(widget)
    QPainterPath path;
    path.addRoundedRect(m_rect, 5, 5);
 
    QPointF anchor = mapFromParent(m_anchor);
    if (!m_rect.contains(anchor)) {
        QPointF point1, point2;
 
        // establish the position of the anchor point in relation to m_rect
        bool above = anchor.y() <= m_rect.top();
        bool aboveCenter = anchor.y() > m_rect.top() && anchor.y() <= m_rect.center().y();
        bool belowCenter = anchor.y() > m_rect.center().y() && anchor.y() <= m_rect.bottom();
        bool below = anchor.y() > m_rect.bottom();
 
        bool onLeft = anchor.x() <= m_rect.left();
        bool leftOfCenter = anchor.x() > m_rect.left() && anchor.x() <= m_rect.center().x();
        bool rightOfCenter = anchor.x() > m_rect.center().x() && anchor.x() <= m_rect.right();
        bool onRight = anchor.x() > m_rect.right();
 
        // get the nearest m_rect corner.
        qreal x = (onRight + rightOfCenter) * m_rect.width();
        qreal y = (below + belowCenter) * m_rect.height();
        bool cornerCase = (above && onLeft) || (above && onRight) || (below && onLeft) || (below && onRight);
        bool vertical = qAbs(anchor.x() - x) > qAbs(anchor.y() - y);
 
        qreal x1 = x + leftOfCenter * 10 - rightOfCenter * 20 + cornerCase * !vertical * (onLeft * 10 - onRight * 20);
        qreal y1 = y + aboveCenter * 10 - belowCenter * 20 + cornerCase * vertical * (above * 10 - below * 20);;
        point1.setX(x1);
        point1.setY(y1);
 
        qreal x2 = x + leftOfCenter * 20 - rightOfCenter * 10 + cornerCase * !vertical * (onLeft * 20 - onRight * 10);;
        qreal y2 = y + aboveCenter * 20 - belowCenter * 10 + cornerCase * vertical * (above * 20 - below * 10);;
        point2.setX(x2);
        point2.setY(y2);
 
        path.moveTo(point1);
        path.lineTo(mapFromParent(m_anchor));
        path.lineTo(point2);
        path = path.simplified();
    }
    painter->setBrush(QColor(255, 255, 255));
    painter->drawPath(path);
    painter->drawText(m_textRect, m_text);
}
 
void Callout::mousePressEvent(QGraphicsSceneMouseEvent *event)
{
    event->setAccepted(true);
}
 
void Callout::mouseMoveEvent(QGraphicsSceneMouseEvent *event)
{
    if (event->buttons() & Qt::LeftButton)
    {
        setPos(mapToParent(event->pos() - event->buttonDownPos(Qt::LeftButton)));
        event->setAccepted(true);
    }
    else
    {
        event->setAccepted(false);
    }
}
 
void Callout::setText(const QString &text)
{
    m_text = text;
    QFontMetrics metrics(m_font);
    m_textRect = metrics.boundingRect(QRect(0, 0, 150, 150), Qt::AlignLeft, m_text);
    m_textRect.translate(5, 5);
    prepareGeometryChange();
    m_rect = m_textRect.adjusted(-5, -5, 5, 5);
}
 
void Callout::setAnchor(QPointF point)
{
    m_anchor = point;
}

/****************************************************************************
**
** Copyright (C) 2016 The Qt Company Ltd.
** Contact: https://www.qt.io/licensing/
**
** This file is part of the Qt Charts module of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:GPL$
** Commercial License Usage
** Licensees holding valid commercial Qt licenses may use this file in
** accordance with the commercial license agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and The Qt Company. For licensing terms
** and conditions see https://www.qt.io/terms-conditions. For further
** information use the contact form at https://www.qt.io/contact-us.
**
** GNU General Public License Usage
** Alternatively, this file may be used under the terms of the GNU
** General Public License version 3 or (at your option) any later version
** approved by the KDE Free Qt Foundation. The licenses are as published by
** the Free Software Foundation and appearing in the file LICENSE.GPL3
** included in the packaging of this file. Please review the following
** information to ensure the GNU General Public License requirements will
** be met: https://www.gnu.org/licenses/gpl-3.0.html.
**
** $QT_END_LICENSE$
**
****************************************************************************/
 
#ifndef CALLOUT_H
#define CALLOUT_H
 
#include <QtWidgets/QGraphicsItem>
#include <QtGui/QFont>
 
QT_BEGIN_NAMESPACE
class QGraphicsSceneMouseEvent;
QT_END_NAMESPACE
 
class Callout : public QGraphicsItem
{
public:
    Callout(QGraphicsItem * parent = 0);
 
    void setText(const QString &text);
    void setAnchor(QPointF point);
 
    QRectF boundingRect() const;
    void paint(QPainter *painter, const QStyleOptionGraphicsItem *option,QWidget *widget);
 
protected:
    void mousePressEvent(QGraphicsSceneMouseEvent *event);
    void mouseMoveEvent(QGraphicsSceneMouseEvent *event);
 
private:
    QString m_text;
    QRectF m_textRect;
    QRectF m_rect;
    QPointF m_anchor;
    QFont m_font;
};
 
#endif // CALLOUT_H

/****************************************************************************
**
** Copyright (C) 2016 The Qt Company Ltd.
** Contact: https://www.qt.io/licensing/
**
** This file is part of the Qt Charts module of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:GPL$
** Commercial License Usage
** Licensees holding valid commercial Qt licenses may use this file in
** accordance with the commercial license agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and The Qt Company. For licensing terms
** and conditions see https://www.qt.io/terms-conditions. For further
** information use the contact form at https://www.qt.io/contact-us.
**
** GNU General Public License Usage
** Alternatively, this file may be used under the terms of the GNU
** General Public License version 3 or (at your option) any later version
** approved by the KDE Free Qt Foundation. The licenses are as published by
** the Free Software Foundation and appearing in the file LICENSE.GPL3
** included in the packaging of this file. Please review the following
** information to ensure the GNU General Public License requirements will
** be met: https://www.gnu.org/licenses/gpl-3.0.html.
**
** $QT_END_LICENSE$
**
****************************************************************************/
 
#ifndef VIEW_H
#define VIEW_H
#include <QtWidgets/QGraphicsView>
#include <QtCharts/QChartGlobal>
#include <QChartView>
#include <QValueAxis>
#include <QLogValueAxis>
#include <QLegendMarker>
#include "Callout.h"
 
QT_BEGIN_NAMESPACE
class QGraphicsScene;
class QMouseEvent;
class QResizeEvent;
QT_END_NAMESPACE
 
QT_CHARTS_BEGIN_NAMESPACE
class QChart;
QT_CHARTS_END_NAMESPACE
QT_CHARTS_USE_NAMESPACE
 
class GraphPage: public QChartView
{
    Q_OBJECT
 
public:
    GraphPage(QChartView *parent = 0);
 
public slots:
    void TooltipShow(QPointF point, bool state);
 
protected:
    void resizeEvent(QResizeEvent *event);
 
private:
    QChart *poChart;
    Callout *poCallout;
 
    void MarkersConnect(QChart *poChart);
 
private slots:
    void HandleMarkerClicked();
 
};
 
#endif