pieview.cpp:5: error: undefined reference to `vtable for PieView'

[Davidcheng]

i add a class named PieView to a mainwindow project , build failed with qt5.9.1 , i dont know what's the problem

#ifndef PIEVIEW_H
#define PIEVIEW_H

#include <QAbstractItemView>
#include <QItemSelectionModel>
#include <QRect>
#include <QRegion>

class PieView : public QAbstractItemView
{
    Q_OBJECT
public:
    PieView(QWidget *parent = 0);
    void paintEvent(QPaintEvent *);

    void setSelectionModel(QItemSelectionModel *selectionModel);
    QRegion itemRegion(QModelIndex index);
    QRect visualRect(const QModelIndex &index) const;
    void scrollTo(const QModelIndex &index, ScrollHint hint = EnsureVisible);

    QModelIndex indexAt(const QPoint &point) const;
    QModelIndex moveCursor(CursorAction cursorAction, Qt::KeyboardModifiers modifiers);
    int horizontalOffset() const;
    int verticalOffset() const;
    bool isIndexHidden(const QModelIndex &index) const;
    void setSelection(const QRect &rect, QItemSelectionModel::SelectionFlags command);

    QRegion visualRegionForSelection(const QItemSelection &selection) const;

private:
    QItemSelectionModel *selections;
    QList<QRegion> RegionList;

};

#endif // PIEVIEW_H

#include "pieview.h"
#include <QPainter>


PieView::PieView(QWidget *parent) : QAbstractItemView(parent)
{

}



void PieView::paintEvent(QPaintEvent *)
{
    QPainter painter(viewport());
    painter.setPen(Qt::black);

    int x0 = 40;
    int y0 = 250;

    painter.drawLine(x0, y0, 40, 30);
    painter.drawLine(38, 32, 40, 30);
    painter.drawLine(40, 30, 42, 32);
    painter.drawText(20, 30, "sell count");

    for(int i = 1; i < 5; i++)
    {
        painter.drawLine(-1, -i*50, 1, -i*50);
        painter.drawText(-20, -i*50, QString("%1").arg(i * 5));
    }

    painter.drawLine(x0, y0, 540, 250);
    painter.drawLine(538, 248, 540, 250);
    painter.drawLine(540, 250, 538, 252);

    painter.drawText(545, 250, "branch");

    int pos = x0 + 20;
    int row;

    for(row = 0; row < model()->rowCount(rootIndex()); row++)
    {

        QModelIndex index = model()->index(row, 0, rootIndex());
        QString dep = model()->data(index).toString();

        painter.drawText(pos, y0 + 20, dep);
        pos += 50;
    }

    int posN = x0 + 20;
    for(row = 0; row < model()->rowCount(rootIndex()); row++)
    {

        QModelIndex index = model()->index(row, 1, rootIndex());
        int sell = model()->data(index).toDouble();
        int width = 10;

        QModelIndex colorIndex = model()->index(row, 0, rootIndex());
        QColor color = QColor(model()->data(colorIndex, Qt::DecorationRole).toString());

        if(selections->isSelected(index))
            painter.setBrush(QBrush(color, Qt::Dense3Pattern));
        else
            painter.setBrush(QBrush(color));

        painter.drawRect(QRect(posN, y0 - 10 * sell, width, 10*sell));

        QRegion regionM(posN, y0 - 10 * sell, width, 10*sell);

        RegionList << regionM;

        posN += 50;
    }

}

void PieView::setSelectionModel(QItemSelectionModel *selectionModel)
{
    selections = selectionModel;
}




QRegion PieView::itemRegion(QModelIndex index)
{
    QRegion region;
    if(index.column() == 1)
        region = RegionList[index.row()];


    return region;
}


QModelIndex PieView::indexAt(const QPoint &point) const
{
    QPoint newPoint(point.x(), point.y());
    QRegion region;

    foreach (region, RegionList)
    {
       if(region.contains(newPoint))
       {
           int row = RegionList.indexOf(region);
           QModelIndex index = model()->index(row, 1, rootIndex());

           return index;
       }
    }

    return QModelIndex();
}

[VRonin]

https://forum.qt.io/search?term=undefined reference to vtable&in=titlesposts&sortBy=relevance&sortDirection=&showAs=posts

[Davidcheng]

Sometimes you have to re-run qmake to catch up changes.