Using QSqlRelationalTableModel
/****************************************************************************
**
** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
** All rights reserved.
** Contact: Nokia Corporation (qt-info@nokia.com)
**
** This file is part of the examples of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** Commercial Usage
** Licensees holding valid Qt Commercial licenses may use this file in
** accordance with the Qt Commercial License Agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and Nokia.
**
** GNU Lesser General Public License Usage
** Alternatively, this file may be used under the terms of the GNU Lesser
** General Public License version 2.1 as published by the Free Software
** Foundation and appearing in the file LICENSE.LGPL included in the
** packaging of this file. Please review the following information to
** ensure the GNU Lesser General Public License version 2.1 requirements
** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
**
** In addition, as a special exception, Nokia gives you certain additional
** rights. These rights are described in the Nokia Qt LGPL Exception
** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
**
** GNU General Public License Usage
** Alternatively, this file may be used under the terms of the GNU
** General Public License version 3.0 as published by the Free Software
** Foundation and appearing in the file LICENSE.GPL included in the
** packaging of this file. Please review the following information to
** ensure the GNU General Public License version 3.0 requirements will be
** met: http://www.gnu.org/copyleft/gpl.html.
**
** If you have questions regarding the use of this file, please contact
** Nokia at qt-info@nokia.com.
** $QT_END_LICENSE$
**
****************************************************************************/
#ifndef CONNECTION_H
#define CONNECTION_H
#include <QMessageBox>
#include <QSqlDatabase>
#include <QSqlError>
#include <QSqlQuery>
/*
This file defines a helper function to open a connection to an
in-memory SQLITE database and to create a test table.
If you want to use another database, simply modify the code
below. All the examples in this directory use this function to
connect to a database.
*/
static bool createConnection()
{
QSqlDatabase db = QSqlDatabase::addDatabase("QSQLITE");
db.setDatabaseName(":memory:");
if (!db.open()) {
QMessageBox::critical(0, qApp->tr("Cannot open database"),
qApp->tr("Unable to establish a database connection.\n"
"This example needs SQLite support. Please read "
"the Qt SQL driver documentation for information how "
"to build it.\n\n"
"Click Cancel to exit."), QMessageBox::Cancel);
return false;
}
QSqlQuery query;
query.exec("create table person (id int primary key, "
"firstname varchar(20), lastname varchar(20))");
query.exec("insert into person values(101, 'Danny', 'Young')");
query.exec("insert into person values(102, 'Christine', 'Holand')");
query.exec("insert into person values(103, 'Lars', 'Gordon')");
query.exec("insert into person values(104, 'Roberto', 'Robitaille')");
query.exec("insert into person values(105, 'Maria', 'Papadopoulos')");
query.exec("create table offices (id int primary key,"
"imagefile int,"
"location varchar(20),"
"country varchar(20),"
"description varchar(100))");
query.exec("insert into offices "
"values(0, 0, 'Oslo', 'Norway',"
"'Oslo is home to more than 500 000 citizens and has a "
"lot to offer.It has been called \"The city with the big "
"heart\" and this is a nickname we are happy to live up to.')");
query.exec("insert into offices "
"values(1, 1, 'Brisbane', 'Australia',"
"'Brisbane is the capital of Queensland, the Sunshine State, "
"where it is beautiful one day, perfect the next. "
"Brisbane is Australia''s 3rd largest city, being home "
"to almost 2 million people.')");
query.exec("insert into offices "
"values(2, 2, 'Redwood City', 'US',"
"'You find Redwood City in the heart of the Bay Area "
"just north of Silicon Valley. The largest nearby city is "
"San Jose which is the third largest city in California "
"and the 10th largest in the US.')");
query.exec("insert into offices "
"values(3, 3, 'Berlin', 'Germany',"
"'Berlin, the capital of Germany is dynamic, cosmopolitan "
"and creative, allowing for every kind of lifestyle. "
"East meets West in the metropolis at the heart of a "
"changing Europe.')");
query.exec("insert into offices "
"values(4, 4, 'Munich', 'Germany',"
"'Several technology companies are represented in Munich, "
"and the city is often called the \"Bavarian Silicon Valley\". "
"The exciting city is also filled with culture, "
"art and music. ')");
query.exec("insert into offices "
"values(5, 5, 'Beijing', 'China',"
"'Beijing as a capital city has more than 3000 years of "
"history. Today the city counts 12 million citizens, and "
"is the political, economic and cultural centre of China.')");
query.exec("create table images (locationid int, file varchar(20))");
query.exec("insert into images values(0, 'images/oslo.png')");
query.exec("insert into images values(1, 'images/brisbane.png')");
query.exec("insert into images values(2, 'images/redwood.png')");
query.exec("insert into images values(3, 'images/berlin.png')");
query.exec("insert into images values(4, 'images/munich.png')");
query.exec("insert into images values(5, 'images/beijing.png')");
return true;
}
#endif
#include <QtGui>
#include <QtSql>
#include "../connection.h"
void initializeModel(QSqlRelationalTableModel *model)
{
model->setTable("employee");
model->setEditStrategy(QSqlTableModel::OnManualSubmit);
model->setRelation(2, QSqlRelation("city", "id", "name"));
model->setRelation(3, QSqlRelation("country", "id", "name"));
model->setHeaderData(0, Qt::Horizontal, QObject::tr("ID"));
model->setHeaderData(1, Qt::Horizontal, QObject::tr("Name"));
model->setHeaderData(2, Qt::Horizontal, QObject::tr("City"));
model->setHeaderData(3, Qt::Horizontal, QObject::tr("Country"));
model->select();
}
QTableView *createView(const QString &title, QSqlTableModel *model)
{
QTableView *view = new QTableView;
view->setModel(model);
view->setItemDelegate(new QSqlRelationalDelegate(view));
view->setWindowTitle(title);
return view;
}
void createRelationalTables()
{
QSqlQuery query;
query.exec("create table employee(id int primary key, name varchar(20), city int, country int)");
query.exec("insert into employee values(1, 'Espen', 5000, 47)");
query.exec("insert into employee values(2, 'Harald', 80000, 49)");
query.exec("insert into employee values(3, 'Sam', 100, 1)");
query.exec("create table city(id int, name varchar(20))");
query.exec("insert into city values(100, 'San Jose')");
query.exec("insert into city values(5000, 'Oslo')");
query.exec("insert into city values(80000, 'Munich')");
query.exec("create table country(id int, name varchar(20))");
query.exec("insert into country values(1, 'USA')");
query.exec("insert into country values(47, 'Norway')");
query.exec("insert into country values(49, 'Germany')");
}
int main(int argc, char *argv[])
{
QApplication app(argc, argv);
if (!createConnection())
return 1;
createRelationalTables();
QSqlRelationalTableModel model;
initializeModel(&model);
QTableView *view = createView(QObject::tr("Relational Table Model"), &model);
view->show();
return app.exec();
}
Related examples in the same category