qt-win/mainwindow.cpp

   1 /****************************************************************************
   2     **
   3     ** Copyright (C) 2004-2005 Trolltech AS. All rights reserved.
   4     **
   5     ** This file is part of the documentation of the Qt Toolkit.
   6     **
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   8 ** License version 2.0 as published by the Free Software Foundation
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  10 ** this file.  Please review the following information to ensure GNU
  11 ** General Public Licensing requirements will be met:
  12 ** http://www.trolltech.com/products/qt/opensource.html
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  15 ** review the following information:
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  17 ** sales department at sales@trolltech.com.
  18     **
  19     ** This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
  20     ** WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  21     **
  22     ****************************************************************************/
  23
  24     #include <QtGui>
  25
  26     #include "mainwindow.h"
  27
  28     MainWindow::MainWindow()
  29     {
  30         textEdit = new QTextEdit;
  31         setCentralWidget(textEdit);
  32
  33         createActions();
  34         createMenus();
  35         createToolBars();
  36         createStatusBar();
  37
  38         readSettings();
  39
  40         connect(textEdit->document(), SIGNAL(contentsChanged()),
  41                 this, SLOT(documentWasModified()));
  42
  43         setCurrentFile("");
  44     }
  45
  46     void MainWindow::closeEvent(QCloseEvent *event)
  47     {
  48         if (maybeSave()) {
  49             writeSettings();
  50             event->accept();
  51         } else {
  52             event->ignore();
  53         }
  54     }
  55
  56     void MainWindow::newFile()
  57     {
  58         if (maybeSave()) {
  59             textEdit->clear();
  60             setCurrentFile("");
  61         }
  62     }
  63
  64     void MainWindow::open()
  65     {
  66         if (maybeSave()) {
  67             QString fileName = QFileDialog::getOpenFileName(this);
  68             if (!fileName.isEmpty())
  69                 loadFile(fileName);
  70         }
  71     }
  72
  73     bool MainWindow::save()
  74     {
  75         if (curFile.isEmpty()) {
  76             return saveAs();
  77         } else {
  78             return saveFile(curFile);
  79         }
  80     }
  81
  82     bool MainWindow::saveAs()
  83     {
  84         QString fileName = QFileDialog::getSaveFileName(this);
  85         if (fileName.isEmpty())
  86             return false;
  87
  88         return saveFile(fileName);
  89     }
  90
  91     void MainWindow::about()
  92     {
  93        QMessageBox::about(this, tr("About Application"),
  94                 tr("The <b>Application</b> example demonstrates how to "
  95                    "write modern GUI applications using Qt, with a menu bar, "
  96                    "toolbars, and a status bar."));
  97     }
  98
  99     void MainWindow::documentWasModified()
 100     {
 101         setWindowModified(true);
 102     }
 103
 104     void MainWindow::createActions()
 105     {
 106         newAct = new QAction(QIcon(":/images/new.png"), tr("&New"), this);
 107         newAct->setShortcut(tr("Ctrl+N"));
 108         newAct->setStatusTip(tr("Create a new file"));
 109         connect(newAct, SIGNAL(triggered()), this, SLOT(newFile()));
 110
 111         openAct = new QAction(QIcon(":/images/open.png"), tr("&Open..."), this);
 112         openAct->setShortcut(tr("Ctrl+O"));
 113         openAct->setStatusTip(tr("Open an existing file"));
 114         connect(openAct, SIGNAL(triggered()), this, SLOT(open()));
 115
 116         saveAct = new QAction(QIcon(":/images/save.png"), tr("&Save"), this);
 117         saveAct->setShortcut(tr("Ctrl+S"));
 118         saveAct->setStatusTip(tr("Save the document to disk"));
 119         connect(saveAct, SIGNAL(triggered()), this, SLOT(save()));
 120
 121         saveAsAct = new QAction(tr("Save &As..."), this);
 122         saveAsAct->setStatusTip(tr("Save the document under a new name"));
 123         connect(saveAsAct, SIGNAL(triggered()), this, SLOT(saveAs()));
 124
 125         exitAct = new QAction(tr("E&xit"), this);
 126         exitAct->setShortcut(tr("Ctrl+Q"));
 127         exitAct->setStatusTip(tr("Exit the application"));
 128         connect(exitAct, SIGNAL(triggered()), this, SLOT(close()));
 129
 130         cutAct = new QAction(QIcon(":/images/cut.png"), tr("Cu&t"), this);
 131         cutAct->setShortcut(tr("Ctrl+X"));
 132         cutAct->setStatusTip(tr("Cut the current selection's contents to the "
 133                                 "clipboard"));
 134         connect(cutAct, SIGNAL(triggered()), textEdit, SLOT(cut()));
 135
 136         copyAct = new QAction(QIcon(":/images/copy.png"), tr("&Copy"), this);
 137         copyAct->setShortcut(tr("Ctrl+C"));
 138         copyAct->setStatusTip(tr("Copy the current selection's contents to the "
 139                                  "clipboard"));
 140         connect(copyAct, SIGNAL(triggered()), textEdit, SLOT(copy()));
 141
 142         pasteAct = new QAction(QIcon(":/images/paste.png"), tr("&Paste"), this);
 143         pasteAct->setShortcut(tr("Ctrl+V"));
 144         pasteAct->setStatusTip(tr("Paste the clipboard's contents into the current "
 145                                   "selection"));
 146         connect(pasteAct, SIGNAL(triggered()), textEdit, SLOT(paste()));
 147
 148         aboutAct = new QAction(tr("&About"), this);
 149         aboutAct->setStatusTip(tr("Show the application's About box"));
 150         connect(aboutAct, SIGNAL(triggered()), this, SLOT(about()));
 151
 152         aboutQtAct = new QAction(tr("About &Qt"), this);
 153         aboutQtAct->setStatusTip(tr("Show the Qt library's About box"));
 154         connect(aboutQtAct, SIGNAL(triggered()), qApp, SLOT(aboutQt()));
 155
 156         cutAct->setEnabled(false);
 157         copyAct->setEnabled(false);
 158         connect(textEdit, SIGNAL(copyAvailable(bool)),
 159                 cutAct, SLOT(setEnabled(bool)));
 160         connect(textEdit, SIGNAL(copyAvailable(bool)),
 161                 copyAct, SLOT(setEnabled(bool)));
 162     }
 163
 164     void MainWindow::createMenus()
 165     {
 166         fileMenu = menuBar()->addMenu(tr("&File"));
 167         fileMenu->addAction(newAct);
 168         fileMenu->addAction(openAct);
 169         fileMenu->addAction(saveAct);
 170         fileMenu->addAction(saveAsAct);
 171         fileMenu->addSeparator();
 172         fileMenu->addAction(exitAct);
 173
 174         editMenu = menuBar()->addMenu(tr("&Edit"));
 175         editMenu->addAction(cutAct);
 176         editMenu->addAction(copyAct);
 177         editMenu->addAction(pasteAct);
 178
 179         menuBar()->addSeparator();
 180
 181         helpMenu = menuBar()->addMenu(tr("&Help"));
 182         helpMenu->addAction(aboutAct);
 183         helpMenu->addAction(aboutQtAct);
 184     }
 185
 186     void MainWindow::createToolBars()
 187     {
 188         fileToolBar = addToolBar(tr("File"));
 189         fileToolBar->addAction(newAct);
 190         fileToolBar->addAction(openAct);
 191         fileToolBar->addAction(saveAct);
 192
 193         editToolBar = addToolBar(tr("Edit"));
 194         editToolBar->addAction(cutAct);
 195         editToolBar->addAction(copyAct);
 196         editToolBar->addAction(pasteAct);
 197     }
 198
 199     void MainWindow::createStatusBar()
 200     {
 201         statusBar()->showMessage(tr("Ready"));
 202     }
 203
 204     void MainWindow::readSettings()
 205     {
 206         QSettings settings("Trolltech", "Application Example");
 207         QPoint pos = settings.value("pos", QPoint(200, 200)).toPoint();
 208         QSize size = settings.value("size", QSize(400, 400)).toSize();
 209         resize(size);
 210         move(pos);
 211     }
 212
 213     void MainWindow::writeSettings()
 214     {
 215         QSettings settings("Trolltech", "Application Example");
 216         settings.setValue("pos", pos());
 217         settings.setValue("size", size());
 218     }
 219
 220     bool MainWindow::maybeSave()
 221     {
 222         if (textEdit->document()->isModified()) {
 223             int ret = QMessageBox::warning(this, tr("Application"),
 224                          tr("The document has been modified.\n"
 225                             "Do you want to save your changes?"),
 226                          QMessageBox::Yes | QMessageBox::Default,
 227                          QMessageBox::No,
 228                          QMessageBox::Cancel | QMessageBox::Escape);
 229             if (ret == QMessageBox::Yes)
 230                 return save();
 231             else if (ret == QMessageBox::Cancel)
 232                 return false;
 233         }
 234         return true;
 235     }
 236
 237     void MainWindow::loadFile(const QString &fileName)
 238     {
 239         QFile file(fileName);
 240         if (!file.open(QFile::ReadOnly | QFile::Text)) {
 241             QMessageBox::warning(this, tr("Application"),
 242                                  tr("Cannot read file %1:\n%2.")
 243                                  .arg(fileName)
 244                                  .arg(file.errorString()));
 245             return;
 246         }
 247
 248         QTextStream in(&file);
 249         QApplication::setOverrideCursor(Qt::WaitCursor);
 250         textEdit->setPlainText(in.readAll());
 251         QApplication::restoreOverrideCursor();
 252
 253         setCurrentFile(fileName);
 254         statusBar()->showMessage(tr("File loaded"), 2000);
 255     }
 256
 257     bool MainWindow::saveFile(const QString &fileName)
 258     {
 259         QFile file(fileName);
 260         if (!file.open(QFile::WriteOnly | QFile::Text)) {
 261             QMessageBox::warning(this, tr("Application"),
 262                                  tr("Cannot write file %1:\n%2.")
 263                                  .arg(fileName)
 264                                  .arg(file.errorString()));
 265             return false;
 266         }
 267
 268         QTextStream out(&file);
 269         QApplication::setOverrideCursor(Qt::WaitCursor);
 270         out << textEdit->toPlainText();
 271         QApplication::restoreOverrideCursor();
 272
 273         setCurrentFile(fileName);
 274         statusBar()->showMessage(tr("File saved"), 2000);
 275         return true;
 276     }
 277
 278     void MainWindow::setCurrentFile(const QString &fileName)
 279     {
 280         curFile = fileName;
 281         textEdit->document()->setModified(false);
 282         setWindowModified(false);
 283
 284         QString shownName;
 285         if (curFile.isEmpty())
 286             shownName = "untitled.txt";
 287         else
 288             shownName = strippedName(curFile);
 289
 290         setWindowTitle(tr("%1[*] - %2").arg(shownName).arg(tr("Application")));
 291     }
 292
 293     QString MainWindow::strippedName(const QString &fullFileName)
 294     {
 295         return QFileInfo(fullFileName).fileName();
 296     }