一个 只读 readonly 示例

stringListModel.cpp

#ifndef STRINGLISTMODEL_H#define STRINGLISTMODEL_H#include <QAbstractListModel>#include <QStringList>class StringListModel : public QAbstractListModel{public:    StringListModel(QObject *parent):QAbstractListModel(parent){}//对QAbstractModel 的部分纯虚函数进行实现    int columnCount(const QModelIndex &parent) const;    int rowCount(const QModelIndex &parent) const;    QVariant data(const QModelIndex &index, int role = Qt::DisplayRole) const;    QVariant headerData(int section, Qt::Orientation orientation, int role = Qt::DisplayRole) const;private:    QStringList StringList;};#endif // STRINGLISTMODEL_H

stringlistmodel.cpp

#include "stringlistmodel.h"#include <qDebug>#include <QFont>#include <QBrush>#include <QPixmap>int StringListModel::columnCount(const QModelIndex &) const{    return 3;}int StringListModel::rowCount(const QModelIndex &) const{    return 2;}QVariant StringListModel::data(const QModelIndex &index, int role) const{    int row = index.row();    int column = index.column();    qDebug()<<QString("Row%1,Column%2").arg(index.row()+1).arg(index.column()+1);    switch(role){    case Qt::BackgroundRole ://背景        if(row == 0 && column == 2){            QBrush color(Qt::red);            return color;        }        if(row == 1 && column == 2){            QPixmap pix("../images/1.jpg");            return pix;        }        break;    case Qt::DisplayRole : //展示        if(row == 0 && column == 1) return QString("<---LEFT");        if(row == 1 && column == 1) return QString("RIGHT--->");        return QString("Row%1,Column%2").arg(index.row()+1).arg(index.column()+1);        break;    case Qt::FontRole : //字体        if(row == 0 && column == 0){            QFont boldFont;            boldFont.setBold(true);            return boldFont;        }        break;    case Qt::TextAlignmentRole :  //对齐        if(row == 1 && column == 1){            return Qt::AlignRight + Qt::AlignVCenter;        }        break;    case Qt::CheckStateRole :  //check框        if(row == 1 && column == 0){            return Qt::Checked;        }    }    return QVariant();}QVariant StringListModel::headerData(int section, Qt::Orientation orientation, int role) const{    return QVariant();}

main.h

#include "widget.h"#include "stringlistmodel.h"#include <QApplication>#include <QTableView>int main(int argc, char *argv[]){    QApplication a(argc, argv);    QTableView * view = new QTableView;    StringListModel * myModel = new StringListModel(0);    view->setModel(myModel);    view->resize(500,300);    view->show();    return a.exec();}

The role parameter is used to let the model know which property is being requested.
ItemDataRole是一个枚举变量，可以在文档里查到：

ItemDataRole-enum