QTableView 数据操作

需求：拖动矩形

效果：

#ifndef RECTDELEGATE_H
#define RECTDELEGATE_H

#include 
class RectDelegate :public QItemDelegate
{
    Q_OBJECT
public:
    RectDelegate(QObject *parent = 0);

private:
    void paint(QPainter* painter,const QStyleOptionViewItem& option,const QModelIndex& index) const;

};

#endif // RECTDELEGATE_H

#include "rectdelegate.h"
#include 

RectDelegate::RectDelegate(QObject *parent) : QItemDelegate(parent)
{

}

void RectDelegate::paint(QPainter *painter, const QStyleOptionViewItem &option,
                         const QModelIndex &index) const
{
    Q_UNUSED(option);
    QPoint point = index.data().toPoint();
    painter->setBrush(QBrush(QColor(120,120,120)));
    painter->drawRect(point.x(), option.rect.y(), point.y(), option.rect.height());
}

#ifndef MYVIEW_H
#define MYVIEW_H

#include 

class QStandardItemModel;

class MyView : public QTableView
{
    Q_OBJECT
public:
    explicit MyView(QWidget *parent = 0);

private:
    void setRect(int row, int column, const QPoint &point);
    bool pointLeftCheck(const QPoint &pos, const QPoint &point);
    bool pointRightCheck(const QPoint &pos, const QPoint &point);

protected:
    void mousePressEvent(QMouseEvent *event);
    void mouseReleaseEvent(QMouseEvent *event);
    void mouseMoveEvent(QMouseEvent *event);

private:
    static const int offset = 2;
    int m_Index;
    bool m_LeftDown;
    bool m_RightDown;
    QStandardItemModel *m_Model;
};

#endif // MYVIEW_H

#include "myview.h"
#include "rectdelegate.h"
#include 
#include 
#include 
#include 

MyView::MyView(QWidget *parent) : QTableView(parent)
{
    m_LeftDown = false;
    m_RightDown = false;
    resize(500,500);

    RectDelegate *ck = new RectDelegate();
    this->setItemDelegateForColumn(1,ck);

    m_Model = new QStandardItemModel();
    m_Model->setRowCount(2);
    m_Model->setColumnCount(2);
    this->setModel(m_Model);
    this->verticalHeader()->setDefaultSectionSize(20);
    this->setEditTriggers(QAbstractItemView::NoEditTriggers);

    //! test
    setRect(0,1,QPoint(100,80));
}

void MyView::setRect(int row, int column, const QPoint &point)
{
    QStandardItem *item = new QStandardItem();
    item->setData(point,Qt::DisplayRole);
    m_Model->setItem( row, column, item );
}

bool MyView::pointLeftCheck(const QPoint &pos, const QPoint &point)
{
    return pos.x() > point.x() - offset && pos.x() < point.x() + offset;
}

bool MyView::pointRightCheck(const QPoint &pos, const QPoint &point)
{
    int width = point.x() + point.y();
    return pos.x() > width - offset && pos.x() < width + offset;
}


void MyView::mousePressEvent(QMouseEvent *event)
{
    QTableView::mousePressEvent(event);
    m_Index = currentIndex().row();
    QPoint && point = currentIndex().data().toPoint();
    QPoint && pos = event->pos();
    if(pointLeftCheck(pos, point)){
        m_LeftDown = true;
        setCursor(Qt::SizeHorCursor);
        return;
    }else if(pointRightCheck(pos, point)){
        m_RightDown = true;
        setCursor(Qt::SizeHorCursor);
        return;
    }
    //!......
}

void MyView::mouseReleaseEvent(QMouseEvent *event)
{
    QTableView::mouseReleaseEvent(event);
    setCursor(Qt::ArrowCursor);
    m_LeftDown = false;
    m_RightDown = false;
}

void MyView::mouseMoveEvent(QMouseEvent *event)
{
    QTableView::mouseMoveEvent(event);
    if(m_Index != currentIndex().row()) return;

    QModelIndex && index = currentIndex();
    QPoint && point = currentIndex().data().toPoint();
    if(m_LeftDown){
        point.setY(point.x() + point.y() - event->pos().x());
        point.setX(event->pos().x());
    }else if(m_RightDown){
        point.setY(event->pos().x() - point.x());
    }
    setRect(index.row(), index.column(), point);
}

#include "myview.h"
#include 

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    MyView view;
    view.show();

    return a.exec();
}