Qt Reference Documentation

# mainwindow.cpp Example File

itemviews/chart/mainwindow.cpp

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     ** This file is part of the examples of the Qt Toolkit.
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     #include <QtGui>

     #include "pieview.h"
     #include "mainwindow.h"

     MainWindow::MainWindow()
     {
         QMenu *fileMenu = new QMenu(tr("&File"), this);
         QAction *openAction = fileMenu->addAction(tr("&Open..."));
         openAction->setShortcuts(QKeySequence::Open);
         QAction *saveAction = fileMenu->addAction(tr("&Save As..."));
         saveAction->setShortcuts(QKeySequence::SaveAs);
         QAction *quitAction = fileMenu->addAction(tr("E&xit"));
         quitAction->setShortcuts(QKeySequence::Quit);

         setupModel();
         setupViews();

         connect(openAction, SIGNAL(triggered()), this, SLOT(openFile()));
         connect(saveAction, SIGNAL(triggered()), this, SLOT(saveFile()));
         connect(quitAction, SIGNAL(triggered()), qApp, SLOT(quit()));

         menuBar()->addMenu(fileMenu);
         statusBar();

         openFile(":/Charts/qtdata.cht");

         setWindowTitle(tr("Chart"));
         resize(870, 550);
     }

     void MainWindow::setupModel()
     {
         model = new QStandardItemModel(8, 2, this);
         model->setHeaderData(0, Qt::Horizontal, tr("Label"));
         model->setHeaderData(1, Qt::Horizontal, tr("Quantity"));
     }

     void MainWindow::setupViews()
     {
         QSplitter *splitter = new QSplitter;
         QTableView *table = new QTableView;
         pieChart = new PieView;
         splitter->addWidget(table);
         splitter->addWidget(pieChart);
         splitter->setStretchFactor(0, 0);
         splitter->setStretchFactor(1, 1);

         table->setModel(model);
         pieChart->setModel(model);

         QItemSelectionModel *selectionModel = new QItemSelectionModel(model);
         table->setSelectionModel(selectionModel);
         pieChart->setSelectionModel(selectionModel);

         QHeaderView *headerView = table->horizontalHeader();
         headerView->setStretchLastSection(true);

         setCentralWidget(splitter);
     }

     void MainWindow::openFile(const QString &path)
     {
         QString fileName;
         if (path.isNull())
             fileName = QFileDialog::getOpenFileName(this, tr("Choose a data file"),
                                                     "", "*.cht");
         else
             fileName = path;

         if (!fileName.isEmpty()) {
             QFile file(fileName);

             if (file.open(QFile::ReadOnly | QFile::Text)) {
                 QTextStream stream(&file);
                 QString line;

                 model->removeRows(0, model->rowCount(QModelIndex()), QModelIndex());

                 int row = 0;
                 do {
                     line = stream.readLine();
                     if (!line.isEmpty()) {

                         model->insertRows(row, 1, QModelIndex());

                         QStringList pieces = line.split(",", QString::SkipEmptyParts);
                         model->setData(model->index(row, 0, QModelIndex()),
                                        pieces.value(0));
                         model->setData(model->index(row, 1, QModelIndex()),
                                        pieces.value(1));
                         model->setData(model->index(row, 0, QModelIndex()),
                                        QColor(pieces.value(2)), Qt::DecorationRole);
                         row++;
                     }
                 } while (!line.isEmpty());

                 file.close();
                 statusBar()->showMessage(tr("Loaded %1").arg(fileName), 2000);
             }
         }
     }

     void MainWindow::saveFile()
     {
         QString fileName = QFileDialog::getSaveFileName(this,
             tr("Save file as"), "", "*.cht");

         if (!fileName.isEmpty()) {
             QFile file(fileName);
             QTextStream stream(&file);

             if (file.open(QFile::WriteOnly | QFile::Text)) {
                 for (int row = 0; row < model->rowCount(QModelIndex()); ++row) {

                     QStringList pieces;

                     pieces.append(model->data(model->index(row, 0, QModelIndex()),
                                               Qt::DisplayRole).toString());
                     pieces.append(model->data(model->index(row, 1, QModelIndex()),
                                               Qt::DisplayRole).toString());
                     pieces.append(model->data(model->index(row, 0, QModelIndex()),
                                               Qt::DecorationRole).toString());

                     stream << pieces.join(",") << "\n";
                 }
             }

             file.close();
             statusBar()->showMessage(tr("Saved %1").arg(fileName), 2000);
         }
     }