如何在qsqlqueryModel(QAbstractItemModel)中编写setdata()

how to write setdata() in qsqlquerymodel(QAbstractItemModel)?

本文关键字:setdata QAbstractItemModel qsqlqueryModel      更新时间:2023-10-16

我使用继承(QSqlQueryModel(和我做了myModel 在其中插入列。我想插入 QString 类型的数据,但我不知道该怎么做。

QSQlQueryModel是只读模型。要使其读写,您必须对其进行子类化并重新实现setData()flags()

我想覆盖这两个方法,这是我到目前为止所做的:
对话框.cpp:

this->model = new myModel(this);
model->setQuery("SELECT * lists");
model->insertColumn(3);
model->setHeaderData(3, Qt::Horizontal, QObject::tr("string"));
qDebug() << model->setData(model->index(0,3),"string",Qt::EditRole);
// column add, column set data using setdata()
ui->tvGameList->setModel(model);

myModel.h:

class myModel : public QSqlQueryModel
{
    Q_OBJECT
public:
    myModel(QObject *parent = 0);
    Qt::ItemFlags flags(const QModelIndex &index) const Q_DECL_OVERRIDE;
    bool setData(const QModelIndex &index, const QVariant &value, int role) Q_DECL_OVERRIDE;
};

我的型号.cpp:

#include "mymodel.h"
#include <QSqlQuery>
myModel::myModel(QObject *parent): QSqlQueryModel(parent)
{
}
Qt::ItemFlags myModel::flags(const QModelIndex &index) const
{
    Qt::ItemFlags flags = QSqlQueryModel::flags(index);
    if (index.column() == 1 || index.column() == 2)
        flags |= Qt::ItemIsEditable;
    return flags;
}
bool myModel::setData(const QModelIndex &index, const QVariant &value, int role = Qt::EditRole)
{
    if (index.isValid() && role == Qt::EditRole)
    {
        // I don't know here
        emit dataChanged(index, index);
        return true;
    }
    return false;
}

参见Qt示例,setData必须像通常SQL一样调用SQL UPDATE语句。

Qt::ItemFlags EditableSqlModel::flags(
    const QModelIndex &index) const
{
 Qt::ItemFlags flags = QSqlQueryModel::flags(index);
 if (index.column() == 1 || index.column() == 2)
     flags |= Qt::ItemIsEditable;
 return flags;
}

bool EditableSqlModel::setData(const QModelIndex &index, const QVariant &value, int /* role */)
{
if (index.column() < 1 || index.column() > 2)
    return false;
QModelIndex primaryKeyIndex = QSqlQueryModel::index(index.row(), 0);
int id = data(primaryKeyIndex).toInt();
clear();
bool ok;
if (index.column() == 1) {
    ok = setFirstName(id, value.toString());
} else {
    ok = setLastName(id, value.toString());
}
refresh();
return ok;
}
bool EditableSqlModel::setFirstName(int personId, const QString &firstName)
{
 QSqlQuery query;
 query.prepare("update person set firstname = ? where id = ?");
 query.addBindValue(firstName);
 query.addBindValue(personId);
 return query.exec();
 }