Qt Reference Documentation

- Qt 4.8
- ALL VERSIONS

- A
- A
- A
- Print

# connectionwidget.cpp Example File

demos/sqlbrowser/connectionwidget.cpp

     /****************************************************************************
     **
     ** Copyright (C) 2015 The Qt Company Ltd.
     ** Contact: http://www.qt.io/licensing/
     **
     ** This file is part of the demonstration applications of the Qt Toolkit.
     **
     ** $QT_BEGIN_LICENSE:LGPL$
     ** Commercial License Usage
     ** Licensees holding valid commercial Qt licenses may use this file in
     ** accordance with the commercial license agreement provided with the
     ** Software or, alternatively, in accordance with the terms contained in
     ** a written agreement between you and The Qt Company. For licensing terms
     ** and conditions see http://www.qt.io/terms-conditions. For further
     ** information use the contact form at http://www.qt.io/contact-us.
     **
     ** 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 or version 3 as published by the Free
     ** Software Foundation and appearing in the file LICENSE.LGPLv21 and
     ** LICENSE.LGPLv3 included in the packaging of this file. Please review the
     ** following information to ensure the GNU Lesser General Public License
     ** requirements will be met: https://www.gnu.org/licenses/lgpl.html and
     ** http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
     **
     ** As a special exception, The Qt Company gives you certain additional
     ** rights. These rights are described in The Qt Company 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.
     **
     ** $QT_END_LICENSE$
     **
     ****************************************************************************/

     #include "connectionwidget.h"

     #include <QtGui>
     #include <QtSql>

     ConnectionWidget::ConnectionWidget(QWidget *parent)
         : QWidget(parent)
     {
         QVBoxLayout *layout = new QVBoxLayout(this);
         tree = new QTreeWidget(this);
         tree->setObjectName(QLatin1String("tree"));
         tree->setHeaderLabels(QStringList(tr("database")));
         tree->header()->setResizeMode(QHeaderView::Stretch);
         QAction *refreshAction = new QAction(tr("Refresh"), tree);
         metaDataAction = new QAction(tr("Show Schema"), tree);
         connect(refreshAction, SIGNAL(triggered()), SLOT(refresh()));
         connect(metaDataAction, SIGNAL(triggered()), SLOT(showMetaData()));
         tree->addAction(refreshAction);
         tree->addAction(metaDataAction);
         tree->setContextMenuPolicy(Qt::ActionsContextMenu);

         layout->addWidget(tree);

         QMetaObject::connectSlotsByName(this);
     }

     ConnectionWidget::~ConnectionWidget()
     {
     }

     static QString qDBCaption(const QSqlDatabase &db)
     {
         QString nm = db.driverName();
         nm.append(QLatin1Char(':'));
         if (!db.userName().isEmpty())
             nm.append(db.userName()).append(QLatin1Char('@'));
         nm.append(db.databaseName());
         return nm;
     }

     void ConnectionWidget::refresh()
     {
         tree->clear();
         QStringList connectionNames = QSqlDatabase::connectionNames();

         bool gotActiveDb = false;
         for (int i = 0; i < connectionNames.count(); ++i) {
             QTreeWidgetItem *root = new QTreeWidgetItem(tree);
             QSqlDatabase db = QSqlDatabase::database(connectionNames.at(i), false);
             root->setText(0, qDBCaption(db));
             if (connectionNames.at(i) == activeDb) {
                 gotActiveDb = true;
                 setActive(root);
             }
             if (db.isOpen()) {
                 QStringList tables = db.tables();
                 for (int t = 0; t < tables.count(); ++t) {
                     QTreeWidgetItem *table = new QTreeWidgetItem(root);
                     table->setText(0, tables.at(t));
                 }
             }
         }
         if (!gotActiveDb) {
             activeDb = connectionNames.value(0);
             setActive(tree->topLevelItem(0));
         }

         tree->doItemsLayout(); // HACK
     }

     QSqlDatabase ConnectionWidget::currentDatabase() const
     {
         return QSqlDatabase::database(activeDb);
     }

     static void qSetBold(QTreeWidgetItem *item, bool bold)
     {
         QFont font = item->font(0);
         font.setBold(bold);
         item->setFont(0, font);
     }

     void ConnectionWidget::setActive(QTreeWidgetItem *item)
     {
         for (int i = 0; i < tree->topLevelItemCount(); ++i) {
             if (tree->topLevelItem(i)->font(0).bold())
                 qSetBold(tree->topLevelItem(i), false);
         }

         if (!item)
             return;

         qSetBold(item, true);
         activeDb = QSqlDatabase::connectionNames().value(tree->indexOfTopLevelItem(item));
     }

     void ConnectionWidget::on_tree_itemActivated(QTreeWidgetItem *item, int /* column */)
     {

         if (!item)
             return;

         if (!item->parent()) {
             setActive(item);
         } else {
             setActive(item->parent());
             emit tableActivated(item->text(0));
         }
     }

     void ConnectionWidget::showMetaData()
     {
         QTreeWidgetItem *cItem = tree->currentItem();
         if (!cItem || !cItem->parent())
             return;
         setActive(cItem->parent());
         emit metaDataRequested(cItem->text(0));
     }

     void ConnectionWidget::on_tree_currentItemChanged(QTreeWidgetItem *current, QTreeWidgetItem *)
     {
         metaDataAction->setEnabled(current && current->parent());
     }