Qt 4.8: mainwindow.cpp Example File (itemviews/editabletreemodel/mainwindow.cpp)

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# mainwindow.cpp Example File

itemviews/editabletreemodel/mainwindow.cpp

     /****************************************************************************
     **
     ** Copyright (C) 2015 The Qt Company Ltd.
     ** Contact: http://www.qt.io/licensing/
     **
     ** This file is part of the examples of the Qt Toolkit.
     **
     ** $QT_BEGIN_LICENSE:BSD$
     ** You may use this file under the terms of the BSD license as follows:
     **
     ** "Redistribution and use in source and binary forms, with or without
     ** modification, are permitted provided that the following conditions are
     ** met:
     **   * Redistributions of source code must retain the above copyright
     **     notice, this list of conditions and the following disclaimer.
     **   * Redistributions in binary form must reproduce the above copyright
     **     notice, this list of conditions and the following disclaimer in
     **     the documentation and/or other materials provided with the
     **     distribution.
     **   * Neither the name of The Qt Company Ltd nor the names of its
     **     contributors may be used to endorse or promote products derived
     **     from this software without specific prior written permission.
     **
     **
     ** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
     ** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
     ** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
     ** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
     ** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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     ** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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     ** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
     ** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
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     ****************************************************************************/

     #include <QtGui>

     #include "mainwindow.h"
     #include "treemodel.h"

     MainWindow::MainWindow(QWidget *parent)
         : QMainWindow(parent)
     {
         setupUi(this);

     #ifdef Q_WS_MAEMO_5
         // Alternating row colors look bad on Maemo
         view->setAlternatingRowColors(false);
     #endif

         QStringList headers;
         headers << tr("Title") << tr("Description");

         QFile file(":/default.txt");
         file.open(QIODevice::ReadOnly);
         TreeModel *model = new TreeModel(headers, file.readAll());
         file.close();

         view->setModel(model);
         for (int column = 0; column < model->columnCount(); ++column)
             view->resizeColumnToContents(column);

         connect(exitAction, SIGNAL(triggered()), qApp, SLOT(quit()));

         connect(view->selectionModel(),
                 SIGNAL(selectionChanged(const QItemSelection &,
                                         const QItemSelection &)),
                 this, SLOT(updateActions()));

         connect(actionsMenu, SIGNAL(aboutToShow()), this, SLOT(updateActions()));
         connect(insertRowAction, SIGNAL(triggered()), this, SLOT(insertRow()));
         connect(insertColumnAction, SIGNAL(triggered()), this, SLOT(insertColumn()));
         connect(removeRowAction, SIGNAL(triggered()), this, SLOT(removeRow()));
         connect(removeColumnAction, SIGNAL(triggered()), this, SLOT(removeColumn()));
         connect(insertChildAction, SIGNAL(triggered()), this, SLOT(insertChild()));

         updateActions();
     }

     void MainWindow::insertChild()
     {
         QModelIndex index = view->selectionModel()->currentIndex();
         QAbstractItemModel *model = view->model();

         if (model->columnCount(index) == 0) {
             if (!model->insertColumn(0, index))
                 return;
         }

         if (!model->insertRow(0, index))
             return;

         for (int column = 0; column < model->columnCount(index); ++column) {
             QModelIndex child = model->index(0, column, index);
             model->setData(child, QVariant("[No data]"), Qt::EditRole);
             if (!model->headerData(column, Qt::Horizontal).isValid())
                 model->setHeaderData(column, Qt::Horizontal, QVariant("[No header]"),
                                      Qt::EditRole);
         }

         view->selectionModel()->setCurrentIndex(model->index(0, 0, index),
                                                 QItemSelectionModel::ClearAndSelect);
         updateActions();
     }

     bool MainWindow::insertColumn(const QModelIndex &parent)
     {
         QAbstractItemModel *model = view->model();
         int column = view->selectionModel()->currentIndex().column();

         // Insert a column in the parent item.
         bool changed = model->insertColumn(column + 1, parent);
         if (changed)
             model->setHeaderData(column + 1, Qt::Horizontal, QVariant("[No header]"),
                                  Qt::EditRole);

         updateActions();

         return changed;
     }

     void MainWindow::insertRow()
     {
         QModelIndex index = view->selectionModel()->currentIndex();
         QAbstractItemModel *model = view->model();

         if (!model->insertRow(index.row()+1, index.parent()))
             return;

         updateActions();

         for (int column = 0; column < model->columnCount(index.parent()); ++column) {
             QModelIndex child = model->index(index.row()+1, column, index.parent());
             model->setData(child, QVariant("[No data]"), Qt::EditRole);
         }
     }

     bool MainWindow::removeColumn(const QModelIndex &parent)
     {
         QAbstractItemModel *model = view->model();
         int column = view->selectionModel()->currentIndex().column();

         // Insert columns in each child of the parent item.
         bool changed = model->removeColumn(column, parent);

         if (!parent.isValid() && changed)
             updateActions();

         return changed;
     }

     void MainWindow::removeRow()
     {
         QModelIndex index = view->selectionModel()->currentIndex();
         QAbstractItemModel *model = view->model();
         if (model->removeRow(index.row(), index.parent()))
             updateActions();
     }

     void MainWindow::updateActions()
     {
         bool hasSelection = !view->selectionModel()->selection().isEmpty();
         removeRowAction->setEnabled(hasSelection);
         removeColumnAction->setEnabled(hasSelection);

         bool hasCurrent = view->selectionModel()->currentIndex().isValid();
         insertRowAction->setEnabled(hasCurrent);
         insertColumnAction->setEnabled(hasCurrent);

         if (hasCurrent) {
             view->closePersistentEditor(view->selectionModel()->currentIndex());

             int row = view->selectionModel()->currentIndex().row();
             int column = view->selectionModel()->currentIndex().column();
             if (view->selectionModel()->currentIndex().parent().isValid())
                 statusBar()->showMessage(tr("Position: (%1,%2)").arg(row).arg(column));
             else
                 statusBar()->showMessage(tr("Position: (%1,%2) in top level").arg(row).arg(column));
         }
     }