Question

所以我有谷歌这个问题并搜索这个网站，但我发现的一切都不起作用。以下是头文件中的麻烦行：

ChartView(QChart *chart, QWidget *parent = 0);
QLineSeries *hLine;
QLineSeries *vLine;
bool isDoneDrawing;
void doneDrawing(bool newValue);

这是头文件：

 #ifndef CHARTVIEW_H
 #define CHARTVIEW_H

 #include <QtCharts/QChartView>
 #include <QtWidgets>
 #include <QtCharts>

 QT_CHARTS_USE_NAMESPACE


 class ChartView : public QChartView
 {
 public:
     ChartView(QChart *chart, QWidget *parent = 0);
     QLineSeries *hLine;
     QLineSeries *vLine;
     bool isDoneDrawing;
     void doneDrawing(bool newValue);

 protected:
     void mouseMoveEvent(QMouseEvent *event);

 };

 #endif

这是ccp文件：

    #include <QtWidgets>
#include <QtCharts>
#include "chartview.h"

ChartView::ChartView(QChart *chart, QWidget *parent) :
    QChartView(chart, parent){
    isDoneDrawing = false;
    hLine = new QLineSeries();
    hLine->setPen(QPen(QColor(Qt::white), 0.5, Qt::DotLine));
    chart->addSeries(hLine);
    //this->chart()->addSeries(hLine);

    vLine = new QLineSeries();
    vLine->setPen(QPen(QColor(Qt::white), 0.5, Qt::DotLine));
    chart->addSeries(vLine);
    //this->chart()->addSeries(vLine);

    setContentsMargins(0,0,0,0);



}

void ChartView::doneDrawing(bool newValue){
    isDoneDrawing = newValue;
}

void ChartView::mouseMoveEvent(QMouseEvent *event){
    if(isDoneDrawing){
        //draw horizontal line
        double y = double(event->pos().y());
        if(y < this->chart()->plotArea().bottom() && y > this->chart()->plotArea().top()){
            this->chart()->removeSeries(hLine);
            double min = this->chart()->property("yMin").toDouble();
            double max = this->chart()->property("yMax").toDouble();
            //rescale y
            y = (max-min)*(y-this->chart()->plotArea().top())/(this->chart()->plotArea().bottom()-this->chart()->plotArea().top())+min;
            //invert y
            y= (max+min)-y;
            hLine->clear();
            hLine->append(0,y);
            hLine->append(this->chart()->plotArea().right(),y);
            hLine->append(this->chart()->size().width(),y);
            this->chart()->addSeries(hLine);
            hLine->attachAxis(this->chart()->axisY());
            hLine->attachAxis(this->chart()->axisX());
        }

        //draw vertical line
        double x = double(event->pos().x());
        if(x < this->chart()->plotArea().right() && x > this->chart()->plotArea().left()){
            this->chart()->removeSeries(vLine);
            double min = this->chart()->property("xMin").toDouble();
            double max = this->chart()->property("xMax").toDouble();
            //rescale x
            x = (max-min)*(x-this->chart()->plotArea().right())/(this->chart()->plotArea().left()-this->chart()->plotArea().right())+min;


            //update price info in title
            QStringList data = this->chart()->property(QString::number((int)x).toUtf8()).toString().split(',');
            QString title;
            QString dataColor = this->chart()->series().at(0)->property(QString::number((int)x).toUtf8()).toString();
            title = this->chart()->property("newTitle").toString().append("<table  style='color:"+dataColor+"; font-size:10px'><tr><td width='100'>Date:<br>").append(data[0]);
            title.append("</td><td width='50'>Open:<br>").append(data[3]);
            title.append("</td><td width='50'>High:<br>").append(data[4]);
            title.append("</td><td width='50'>Low:<br>").append(data[1]);
            title.append("</td><td width='50'>Close:<br>").append(data[2]);
            title.append("</td><td width='50'>High:<br>").append(data[5]);
            title.append("</td><td width='50'>Low:<br>").append(data[6]);
            if(data.size() > 7){
                title.append("</td><td width='50'>PC:<br>").append(data[7]);
            }else{
                title.append("</td><td width='50'>PC:<br>");
            }
            title.append("</td></tr></table>");
            this->chart()->setTitle(title);


            //invert x
            x= (max+min)-x;
            vLine->clear();
            vLine->append(x,this->chart()->size().height());
            vLine->append(x,0);
            this->chart()->addSeries(vLine);
            vLine->attachAxis(this->chart()->axisY());
            vLine->attachAxis(this->chart()->axisX());
        }
    }
}

我尝试在每个声明之前添加extern，但找不到我错过的地方';'在一条线的尽头。任何帮助都会很棒。我正在使用全新安装的Ubuntu和Qt Creator。该项目已从我之前的安装中导入。

希望这是足够的信息。关于这个错误的许多其他问题都缺乏信息，所以我希望这个问题也能解决这个问题。

以下是错误代码：

/home/bandito/programming/build-etf-ipo-new-Unnamed-Debug/chartview.o:-1：在函数QList<QtCharts::QAbstractSeries*>::node_destruct(QList<QtCharts::QAbstractSeries*>::Node*, QList<QtCharts::QAbstractSeries*>::Node*)': /home/bandito/programming/etf-ipo-new/chartview.cpp:5: error: multiple definition of ChartView :: ChartView（QtCharts :: QChart *，QWidget *） “ /home/bandito/programming/etf-ipo-new/chartview.cpp:5：首先在这里定义 /home/bandito/programming/build-etf-ipo-new-Unnamed-Debug/chartview.o:-1：功能 QList<QtCharts::QAbstractSeries*>::node_destruct(QList<QtCharts::QAbstractSeries*>::Node*, QList<QtCharts::QAbstractSeries*>::Node*)': /home/bandito/programming/etf-ipo-new/chartview.cpp:5: error: multiple definition of ChartView :: ChartView（QtCharts :: QChart *，QWidget *）' /home/bandito/programming/etf-ipo-new/chartview.cpp:5：首先在这里定义 /home/bandito/programming/build-etf-ipo-new-Unnamed-Debug/chartview.o:-1：功能 ChartView::doneDrawing(bool)': /home/bandito/programming/etf-ipo-new/chartview.cpp:24: error: multiple definition of ChartView :: doneDrawing（布尔）” /home/bandito/programming/etf-ipo-new/chartview.cpp:24：首先在这里定义 /home/bandito/programming/build-etf-ipo-new-Unnamed-Debug/chartview.o:-1：功能 ChartView::mouseMoveEvent(QMouseEvent*)': /home/bandito/programming/etf-ipo-new/chartview.cpp:28: error: multiple definition of ChartView :: mouseMoveEvent（QMouseEvent *）” /home/bandito/programming/etf-ipo-new/chartview.cpp:28：首先在这里定义：-1：错误：collect2：错误：ld返回1退出状态

Qt：无法解决错误：多重定义

0 个答案: