C++/Qt/Window

MdiWindow based editor

<source lang="cpp"> Foundations of Qt Development\Chapter04\mdi\documentwindow.cpp /*

* Copyright (c) 2006-2007, Johan Thelin
* 
* All rights reserved.
* 
* 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 APress 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, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
*/

1. include <QApplication>
2. include <QMenuBar>
3. include <QToolBar>
4. include <QStatusBar>
5. include <QCloseEvent>
6. include <QMessageBox>
7. include <QTextEdit>
8. include "documentwindow.h"

DocumentWindow::DocumentWindow( QWidget *parent ) : QTextEdit( parent ) {

 setAttribute( Qt::WA_DeleteOnClose );
 setWindowTitle( tr("%1[*]" ).arg("unnamed") );
 
 connect( document(), SIGNAL(modificationChanged(bool)), this, SLOT(setWindowModified(bool)) );

}

void DocumentWindow::closeEvent( QCloseEvent *event ) {

 if( isSafeToClose() )
   event->accept();
 else
   event->ignore();

} bool DocumentWindow::isSafeToClose() {

 if( document()->isModified() ) 
 {
   switch( QMessageBox::warning( this, tr("MDI"), 
     tr("The document has unsaved changes.\n"
        "Do you want to save it before it is closed?"), 
        QMessageBox::Discard | QMessageBox::Cancel ) )
   {
   case QMessageBox::Cancel:
     return false;
   default:
     return true;
   }
 }
 return true;

}

Foundations of Qt Development\Chapter04\mdi\documentwindow.h /*

* Copyright (c) 2006-2007, Johan Thelin
* 
* All rights reserved.
* 
* 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 APress 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, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
*/

1. ifndef DOCUMENTWINDOW_H
2. define DOCUMENTWINDOW_H
3. include <QTextEdit>

class DocumentWindow : public QTextEdit {

 Q_OBJECT
 

public:

 DocumentWindow( QWidget *parent = 0 );
 

protected:

 void closeEvent( QCloseEvent *event );
 

private:

 bool isSafeToClose();

};

1. endif // DOCUMENTWINDOW_H

Foundations of Qt Development\Chapter04\mdi\main.cpp /*

* Copyright (c) 2006-2007, Johan Thelin
* 
* All rights reserved.
* 
* 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 APress 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, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
*/

1. include <QApplication>
2. include "mdiwindow.h"

int main( int argc, char **argv ) {

 QApplication app( argc, argv );
 
 MdiWindow win;
 win.show();
 
 return app.exec();

}

Foundations of Qt Development\Chapter04\mdi\mdiwindow.cpp /*

* Copyright (c) 2006-2007, Johan Thelin
* 
* All rights reserved.
* 
* 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 APress 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, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
*/

1. include <QApplication>
2. include <QMenuBar>
3. include <QToolBar>
4. include <QStatusBar>
5. include <QCloseEvent>
6. include <QMessageBox>
7. include <QWorkspace>
8. include <QSignalMapper>
9. include "mdiwindow.h"
10. include "documentwindow.h"

MdiWindow::MdiWindow( QWidget *parent ) : QMainWindow( parent ) {

 setWindowTitle( tr( "MDI" ) );
 workspace = new QWorkspace;
 setCentralWidget( workspace );
 
 connect( workspace, SIGNAL(windowActivated(QWidget *)), this, SLOT(enableActions()));
 mapper = new QSignalMapper( this );
 connect( mapper, SIGNAL(mapped(QWidget*)), workspace, SLOT(setActiveWindow(QWidget*)) );
 createActions();
 createMenus();
 createToolbars();
 statusBar()->showMessage( tr("Done") );
 
 enableActions();

}

void MdiWindow::closeEvent( QCloseEvent *event ) {

 workspace->closeAllWindows();
 if( !activeDocument() )
   event->accept();
 else
   event->ignore();

}

void MdiWindow::fileNew() {

 DocumentWindow *document = new DocumentWindow;
 workspace->addWindow( document );
 connect( document, SIGNAL(copyAvailable(bool)), cutAction, SLOT(setEnabled(bool)) );
 connect( document, SIGNAL(copyAvailable(bool)), copyAction, SLOT(setEnabled(bool)) );
 
 document->show();

} void MdiWindow::helpAbout() {

 QMessageBox::about( this, tr("About MDI"), tr("A multiple document interface application.") );

} DocumentWindow *MdiWindow::activeDocument() {

 return qobject_cast<DocumentWindow*>(workspace->activeWindow());

} void MdiWindow::enableActions() {

 bool hasDocuments = (activeDocument() != 0 );
 
 closeAction->setEnabled( hasDocuments );  
 pasteAction->setEnabled( hasDocuments );  
 tileAction->setEnabled( hasDocuments );
 cascadeAction->setEnabled( hasDocuments );
 nextAction->setEnabled( hasDocuments );
 previousAction->setEnabled( hasDocuments );
 separatorAction->setVisible( hasDocuments );
 bool hasSelection = hasDocuments && activeDocument()->textCursor().hasSelection();
 cutAction->setEnabled( hasSelection );  
 copyAction->setEnabled( hasSelection );  

} void MdiWindow::createActions() {

 newAction = new QAction( QIcon(":/images/new.png"), tr("&New"), this );
 newAction->setShortcut( tr("Ctrl+N") );
 newAction->setStatusTip( tr("Create a new document") );
 connect( newAction, SIGNAL(triggered()), this, SLOT(fileNew()) );
 
 closeAction = new QAction( tr("&Close"), this );
 closeAction->setShortcut( tr("Ctrl+W") );
 closeAction->setStatusTip( tr("Close this document") );
 connect( closeAction, SIGNAL(triggered()), workspace, SLOT(closeActiveWindow()) );
 exitAction = new QAction( tr("E&xit"), this );
 exitAction->setShortcut( tr("Ctrl+Q") );
 exitAction->setStatusTip( tr("Quit the application") );
 connect( exitAction, SIGNAL(triggered()), qApp, SLOT(closeAllWindows()) );
 
 cutAction = new QAction( QIcon(":/images/cut.png"), tr("Cu&t"), this );
 cutAction->setShortcut( tr("Ctrl+X") );
 cutAction->setStatusTip( tr("Cut") );
 cutAction->setEnabled(false);
 connect( cutAction, SIGNAL(triggered()), this, SLOT(editCut()) );
 
 copyAction = new QAction( QIcon(":/images/copy.png"), tr("&Copy"), this );
 copyAction->setShortcut( tr("Ctrl+C") );
 copyAction->setStatusTip( tr("Copy") );
 copyAction->setEnabled(false);
 connect( copyAction, SIGNAL(triggered()), this, SLOT(editCopy()) );
 pasteAction = new QAction( QIcon(":/images/paste.png"), tr("&Paste"), this );
 pasteAction->setShortcut( tr("Ctrl+V") );
 pasteAction->setStatusTip( tr("Paste") );
 connect( pasteAction, SIGNAL(triggered()), this, SLOT(editPaste()) );
 
 tileAction = new QAction( tr("&Tile"), this );
 tileAction->setStatusTip( tr("Tile the windows") );
 connect( tileAction, SIGNAL(triggered()), workspace, SLOT(tile()) );
 
 cascadeAction = new QAction( tr("&Cascade"), this );
 cascadeAction->setStatusTip( tr("Cascade the windows") );
 connect( cascadeAction, SIGNAL(triggered()), workspace, SLOT(cascade()) );
 nextAction = new QAction( tr("&Next window"), this );
 nextAction->setStatusTip( tr("Move to the next window") );
 connect( nextAction, SIGNAL(triggered()), workspace, SLOT(activateNextWindow()) );
 
 previousAction = new QAction( tr("&Previous window"), this );
 previousAction->setStatusTip( tr("Move to the previous window") );
 connect( previousAction, SIGNAL(triggered()), workspace, SLOT(activatePreviousWindow()) );
 
 separatorAction = new QAction( this );
 separatorAction->setSeparator( true );
 
 aboutAction = new QAction( tr("&About"), this );
 aboutAction->setStatusTip( tr("About this application") );
 connect( aboutAction, SIGNAL(triggered()), this, SLOT(helpAbout()) );
 aboutQtAction = new QAction( tr("About &Qt"), this );
 aboutQtAction->setStatusTip( tr("About the Qt toolkit") );
 connect( aboutQtAction, SIGNAL(triggered()), qApp, SLOT(aboutQt()) );

} void MdiWindow::createMenus() {

 QMenu *menu;
 
 menu = menuBar()->addMenu( tr("&File") );
 menu->addAction( newAction );
 menu->addAction( closeAction );
 menu->addSeparator();
 menu->addAction( exitAction );
 
 menu = menuBar()->addMenu( tr("&Edit") );
 menu->addAction( cutAction );
 menu->addAction( copyAction );
 menu->addAction( pasteAction );
 
 windowMenu = menuBar()->addMenu( tr("&Window") );
 connect( windowMenu, SIGNAL(aboutToShow()), this, SLOT(updateWindowList()) );
 
 menu = menuBar()->addMenu( tr("&Help") );
 menu->addAction( aboutAction );
 menu->addAction( aboutQtAction );

} void MdiWindow::createToolbars() {

 QToolBar *toolbar;
 
 toolbar = addToolBar( tr("File") );
 toolbar->addAction( newAction );
 
 toolbar = addToolBar( tr("Edit") );
 toolbar->addAction( cutAction );
 toolbar->addAction( copyAction );
 toolbar->addAction( pasteAction );

} void MdiWindow::editCut() {

 activeDocument()->cut();

}

void MdiWindow::editCopy() {

 activeDocument()->copy();

}

void MdiWindow::editPaste() {

 activeDocument()->paste();

} void MdiWindow::updateWindowList() {

 windowMenu->clear();
 
 windowMenu->addAction( tileAction );
 windowMenu->addAction( cascadeAction );
 windowMenu->addSeparator();
 windowMenu->addAction( nextAction );
 windowMenu->addAction( previousAction );
 windowMenu->addAction( separatorAction );
 
 int i=1;
 foreach( QWidget *w, workspace->windowList() )
 {
   QString text;
   if( i<10 )
     text = tr("&%1 %2").arg( i++ ).arg( w->windowTitle() );
   else
     text = w->windowTitle();
     
   QAction *action = windowMenu->addAction( text );
   action->setCheckable( true );
   action->setChecked( w == activeDocument() );
   connect( action, SIGNAL(triggered()), mapper, SLOT(map()) );
   mapper->setMapping( action, w );
 }

}

Foundations of Qt Development\Chapter04\mdi\mdiwindow.h /*

* Copyright (c) 2006-2007, Johan Thelin
* 
* All rights reserved.
* 
* 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 APress 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, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
*/

1. ifndef MDIWINDOW_H
2. define MDIWINDOW_H
3. include <QMainWindow>

class QAction; class QWorkspace; class QSignalMapper; class QMenu; class DocumentWindow; class MdiWindow : public QMainWindow {

 Q_OBJECT
 

public:

 MdiWindow( QWidget *parent = 0 );
 

protected:

 void closeEvent( QCloseEvent *event );
 

private slots:

 void fileNew();
 
 void editCut();
 void editCopy();
 void editPaste();
 
 void helpAbout();
 
 void enableActions();
 void updateWindowList();

private:

 void createActions();
 void createMenus();
 void createToolbars();
 DocumentWindow *activeDocument();
 QWorkspace *workspace;
 QSignalMapper *mapper;
 
 QAction *newAction;
 QAction *closeAction;
 QAction *exitAction;
 
 QAction *cutAction;
 QAction *copyAction;
 QAction *pasteAction;
 
 QAction *tileAction;
 QAction *cascadeAction;
 QAction *nextAction;
 QAction *previousAction;
 QAction *separatorAction;
 
 QAction *aboutAction;
 QAction *aboutQtAction;
 
 QMenu *windowMenu;

};

1. endif // MDIWINDOW_H

 </source>

Qt based application window

<source lang="cpp"> /****************************************************************************

• • 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.
  • $QT_END_LICENSE$
  • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • /

1. ifndef MAINWINDOW_H
2. define MAINWINDOW_H
3. include <QMainWindow>

QT_BEGIN_NAMESPACE class QAction; class QMenu; class QPlainTextEdit; QT_END_NAMESPACE

class MainWindow : public QMainWindow {

   Q_OBJECT

public:

   MainWindow();

protected:

   void closeEvent(QCloseEvent *event);

private slots:

   void newFile();
   void open();
   bool save();
   bool saveAs();
   void about();
   void documentWasModified();

private:

   void createActions();
   void createMenus();
   void createToolBars();
   void createStatusBar();
   void readSettings();
   void writeSettings();
   bool maybeSave();
   void loadFile(const QString &fileName);
   bool saveFile(const QString &fileName);
   void setCurrentFile(const QString &fileName);
   QString strippedName(const QString &fullFileName);
   QPlainTextEdit *textEdit;
   QString curFile;
   QMenu *fileMenu;
   QMenu *editMenu;
   QMenu *helpMenu;
   QToolBar *fileToolBar;
   QToolBar *editToolBar;
   QAction *newAct;
   QAction *openAct;
   QAction *saveAct;
   QAction *saveAsAct;
   QAction *exitAct;
   QAction *cutAct;
   QAction *copyAct;
   QAction *pasteAct;
   QAction *aboutAct;
   QAction *aboutQtAct;

};

1. endif

1. include <QtGui>
2. include "mainwindow.h"

MainWindow::MainWindow()

{

   textEdit = new QPlainTextEdit;
   setCentralWidget(textEdit);
   createActions();
   createMenus();
   createToolBars();
   createStatusBar();
   readSettings();
   connect(textEdit->document(), SIGNAL(contentsChanged()),
           this, SLOT(documentWasModified()));
   setCurrentFile("");
   setUnifiedTitleAndToolBarOnMac(true);

}

void MainWindow::closeEvent(QCloseEvent *event)

{

   if (maybeSave()) {
       writeSettings();
       event->accept();
   } else {
       event->ignore();
   }

}

void MainWindow::newFile()

{

   if (maybeSave()) {
       textEdit->clear();
       setCurrentFile("");
   }

}

void MainWindow::open()

{

   if (maybeSave()) {
       QString fileName = QFileDialog::getOpenFileName(this);
       if (!fileName.isEmpty())
           loadFile(fileName);
   }

}

bool MainWindow::save()

{

   if (curFile.isEmpty()) {
       return saveAs();
   } else {
       return saveFile(curFile);
   }

}

bool MainWindow::saveAs()

{

   QString fileName = QFileDialog::getSaveFileName(this);
   if (fileName.isEmpty())
       return false;
   return saveFile(fileName);

}

void MainWindow::about()

{

  QMessageBox::about(this, tr("About Application"),
           tr("The Application example demonstrates how to "
              "write modern GUI applications using Qt, with a menu bar, "
              "toolbars, and a status bar."));

}

void MainWindow::documentWasModified()

{

   setWindowModified(textEdit->document()->isModified());

}

void MainWindow::createActions()

{

   newAct = new QAction(QIcon(":/images/new.png"), tr("&New"), this);
   newAct->setShortcuts(QKeySequence::New);
   newAct->setStatusTip(tr("Create a new file"));
   connect(newAct, SIGNAL(triggered()), this, SLOT(newFile()));

   openAct = new QAction(QIcon(":/images/open.png"), tr("&Open..."), this);
   openAct->setShortcuts(QKeySequence::Open);
   openAct->setStatusTip(tr("Open an existing file"));
   connect(openAct, SIGNAL(triggered()), this, SLOT(open()));

   saveAct = new QAction(QIcon(":/images/save.png"), tr("&Save"), this);
   saveAct->setShortcuts(QKeySequence::Save);
   saveAct->setStatusTip(tr("Save the document to disk"));
   connect(saveAct, SIGNAL(triggered()), this, SLOT(save()));
   saveAsAct = new QAction(tr("Save &As..."), this);
   saveAsAct->setShortcuts(QKeySequence::SaveAs);
   saveAsAct->setStatusTip(tr("Save the document under a new name"));
   connect(saveAsAct, SIGNAL(triggered()), this, SLOT(saveAs()));

   exitAct = new QAction(tr("E&xit"), this);
   exitAct->setShortcut(tr("Ctrl+Q"));
   exitAct->setStatusTip(tr("Exit the application"));
   connect(exitAct, SIGNAL(triggered()), this, SLOT(close()));

   cutAct = new QAction(QIcon(":/images/cut.png"), tr("Cu&t"), this);
   cutAct->setShortcuts(QKeySequence::Cut);
   cutAct->setStatusTip(tr("Cut the current selection"s contents to the "
                           "clipboard"));
   connect(cutAct, SIGNAL(triggered()), textEdit, SLOT(cut()));
   copyAct = new QAction(QIcon(":/images/copy.png"), tr("&Copy"), this);
   copyAct->setShortcuts(QKeySequence::Copy);
   copyAct->setStatusTip(tr("Copy the current selection"s contents to the "
                            "clipboard"));
   connect(copyAct, SIGNAL(triggered()), textEdit, SLOT(copy()));
   pasteAct = new QAction(QIcon(":/images/paste.png"), tr("&Paste"), this);
   pasteAct->setShortcuts(QKeySequence::Paste);
   pasteAct->setStatusTip(tr("Paste the clipboard"s contents into the current "
                             "selection"));
   connect(pasteAct, SIGNAL(triggered()), textEdit, SLOT(paste()));
   aboutAct = new QAction(tr("&About"), this);
   aboutAct->setStatusTip(tr("Show the application"s About box"));
   connect(aboutAct, SIGNAL(triggered()), this, SLOT(about()));

   aboutQtAct = new QAction(tr("About &Qt"), this);
   aboutQtAct->setStatusTip(tr("Show the Qt library"s About box"));
   connect(aboutQtAct, SIGNAL(triggered()), qApp, SLOT(aboutQt()));

   cutAct->setEnabled(false);

   copyAct->setEnabled(false);
   connect(textEdit, SIGNAL(copyAvailable(bool)),
           cutAct, SLOT(setEnabled(bool)));
   connect(textEdit, SIGNAL(copyAvailable(bool)),
           copyAct, SLOT(setEnabled(bool)));

}

void MainWindow::createMenus()

{

   fileMenu = menuBar()->addMenu(tr("&File"));
   fileMenu->addAction(newAct);
   fileMenu->addAction(openAct);
   fileMenu->addAction(saveAct);
   fileMenu->addAction(saveAsAct);
   fileMenu->addSeparator();
   fileMenu->addAction(exitAct);
   editMenu = menuBar()->addMenu(tr("&Edit"));
   editMenu->addAction(cutAct);
   editMenu->addAction(copyAct);
   editMenu->addAction(pasteAct);
   menuBar()->addSeparator();
   helpMenu = menuBar()->addMenu(tr("&Help"));
   helpMenu->addAction(aboutAct);
   helpMenu->addAction(aboutQtAct);

}

void MainWindow::createToolBars() {

   fileToolBar = addToolBar(tr("File"));
   fileToolBar->addAction(newAct);

   fileToolBar->addAction(openAct);
   fileToolBar->addAction(saveAct);
   editToolBar = addToolBar(tr("Edit"));
   editToolBar->addAction(cutAct);
   editToolBar->addAction(copyAct);
   editToolBar->addAction(pasteAct);

}

void MainWindow::createStatusBar()

{

   statusBar()->showMessage(tr("Ready"));

}

void MainWindow::readSettings()

{

   QSettings settings("Trolltech", "Application Example");
   QPoint pos = settings.value("pos", QPoint(200, 200)).toPoint();
   QSize size = settings.value("size", QSize(400, 400)).toSize();
   resize(size);
   move(pos);

}

void MainWindow::writeSettings()

{

   QSettings settings("Trolltech", "Application Example");
   settings.setValue("pos", pos());
   settings.setValue("size", size());

}

bool MainWindow::maybeSave()

{

   if (textEdit->document()->isModified()) {
       QMessageBox::StandardButton ret;
       ret = QMessageBox::warning(this, tr("Application"),
                    tr("The document has been modified.\n"
                       "Do you want to save your changes?"),
                    QMessageBox::Save | QMessageBox::Discard | QMessageBox::Cancel);
       if (ret == QMessageBox::Save)
           return save();
       else if (ret == QMessageBox::Cancel)
           return false;
   }
   return true;

}

void MainWindow::loadFile(const QString &fileName)

{

   QFile file(fileName);
   if (!file.open(QFile::ReadOnly | QFile::Text)) {
       QMessageBox::warning(this, tr("Application"),
                            tr("Cannot read file %1:\n%2.")
                            .arg(fileName)
                            .arg(file.errorString()));
       return;
   }
   QTextStream in(&file);
   QApplication::setOverrideCursor(Qt::WaitCursor);
   textEdit->setPlainText(in.readAll());
   QApplication::restoreOverrideCursor();
   setCurrentFile(fileName);
   statusBar()->showMessage(tr("File loaded"), 2000);

}

bool MainWindow::saveFile(const QString &fileName)

{

   QFile file(fileName);
   if (!file.open(QFile::WriteOnly | QFile::Text)) {
       QMessageBox::warning(this, tr("Application"),
                            tr("Cannot write file %1:\n%2.")
                            .arg(fileName)
                            .arg(file.errorString()));
       return false;
   }
   QTextStream out(&file);
   QApplication::setOverrideCursor(Qt::WaitCursor);
   out << textEdit->toPlainText();
   QApplication::restoreOverrideCursor();
   setCurrentFile(fileName);
   statusBar()->showMessage(tr("File saved"), 2000);
   return true;

}

void MainWindow::setCurrentFile(const QString &fileName)

{

   curFile = fileName;
   textEdit->document()->setModified(false);
   setWindowModified(false);
   QString shownName;
   if (curFile.isEmpty())
       shownName = "untitled.txt";
   else
       shownName = strippedName(curFile);
   setWindowTitle(tr("%1[*] - %2").arg(shownName).arg(tr("Application")));

}

QString MainWindow::strippedName(const QString &fullFileName)

{

   return QFileInfo(fullFileName).fileName();

}

1. include <QApplication>
2. include "mainwindow.h"

int main(int argc, char *argv[]) {

   Q_INIT_RESOURCE(application);
   QApplication app(argc, argv);
   MainWindow mainWin;
   mainWin.show();
   return app.exec();

}

 </source>

Qt MDI window

<source lang="cpp"> /****************************************************************************

• • 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.
  • $QT_END_LICENSE$
  • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • /

1. ifndef MDICHILD_H
2. define MDICHILD_H
3. include <QTextEdit>

class MdiChild : public QTextEdit {

   Q_OBJECT

public:

   MdiChild();
   void newFile();
   bool loadFile(const QString &fileName);
   bool save();
   bool saveAs();
   bool saveFile(const QString &fileName);
   QString userFriendlyCurrentFile();
   QString currentFile() { return curFile; }

protected:

   void closeEvent(QCloseEvent *event);

private slots:

   void documentWasModified();

private:

   bool maybeSave();
   void setCurrentFile(const QString &fileName);
   QString strippedName(const QString &fullFileName);
   QString curFile;
   bool isUntitled;

};

1. endif

1. include <QtGui>
2. include "mdichild.h"

MdiChild::MdiChild() {

   setAttribute(Qt::WA_DeleteOnClose);
   isUntitled = true;

} void MdiChild::newFile() {

   static int sequenceNumber = 1;
   isUntitled = true;
   curFile = tr("document%1.txt").arg(sequenceNumber++);
   setWindowTitle(curFile + "[*]");
   connect(document(), SIGNAL(contentsChanged()),
           this, SLOT(documentWasModified()));

} bool MdiChild::loadFile(const QString &fileName) {

   QFile file(fileName);
   if (!file.open(QFile::ReadOnly | QFile::Text)) {
       QMessageBox::warning(this, tr("MDI"),
                            tr("Cannot read file %1:\n%2.")
                            .arg(fileName)
                            .arg(file.errorString()));
       return false;
   }
   QTextStream in(&file);
   QApplication::setOverrideCursor(Qt::WaitCursor);
   setPlainText(in.readAll());
   QApplication::restoreOverrideCursor();
   setCurrentFile(fileName);
   connect(document(), SIGNAL(contentsChanged()),
           this, SLOT(documentWasModified()));
   return true;

} bool MdiChild::save() {

   if (isUntitled) {
       return saveAs();
   } else {
       return saveFile(curFile);
   }

} bool MdiChild::saveAs() {

   QString fileName = QFileDialog::getSaveFileName(this, tr("Save As"),
                                                   curFile);
   if (fileName.isEmpty())
       return false;
   return saveFile(fileName);

} bool MdiChild::saveFile(const QString &fileName) {

   QFile file(fileName);
   if (!file.open(QFile::WriteOnly | QFile::Text)) {
       QMessageBox::warning(this, tr("MDI"),
                            tr("Cannot write file %1:\n%2.")
                            .arg(fileName)
                            .arg(file.errorString()));
       return false;
   }
   QTextStream out(&file);
   QApplication::setOverrideCursor(Qt::WaitCursor);
   out << toPlainText();
   QApplication::restoreOverrideCursor();
   setCurrentFile(fileName);
   return true;

} QString MdiChild::userFriendlyCurrentFile() {

   return strippedName(curFile);

} void MdiChild::closeEvent(QCloseEvent *event) {

   if (maybeSave()) {
       event->accept();
   } else {
       event->ignore();
   }

} void MdiChild::documentWasModified() {

   setWindowModified(document()->isModified());

} bool MdiChild::maybeSave() {

   if (document()->isModified()) {
 QMessageBox::StandardButton ret;
       ret = QMessageBox::warning(this, tr("MDI"),
                    tr(""%1" has been modified.\n"
                       "Do you want to save your changes?")
                    .arg(userFriendlyCurrentFile()),
                    QMessageBox::Save | QMessageBox::Discard
        | QMessageBox::Cancel);
       if (ret == QMessageBox::Save)
           return save();
       else if (ret == QMessageBox::Cancel)
           return false;
   }
   return true;

} void MdiChild::setCurrentFile(const QString &fileName) {

   curFile = QFileInfo(fileName).canonicalFilePath();
   isUntitled = false;
   document()->setModified(false);
   setWindowModified(false);
   setWindowTitle(userFriendlyCurrentFile() + "[*]");

} QString MdiChild::strippedName(const QString &fullFileName) {

   return QFileInfo(fullFileName).fileName();

}

1. ifndef MAINWINDOW_H
2. define MAINWINDOW_H
3. include <QMainWindow>

class MdiChild; QT_BEGIN_NAMESPACE class QAction; class QMenu; class QMdiArea; class QMdiSubWindow; class QSignalMapper; QT_END_NAMESPACE class MainWindow : public QMainWindow {

   Q_OBJECT

public:

   MainWindow();

protected:

   void closeEvent(QCloseEvent *event);

private slots:

   void newFile();
   void open();
   void save();
   void saveAs();
   void cut();
   void copy();
   void paste();
   void about();
   void updateMenus();
   void updateWindowMenu();
   MdiChild *createMdiChild();
   void switchLayoutDirection();
   void setActiveSubWindow(QWidget *window);

private:

   void createActions();
   void createMenus();
   void createToolBars();
   void createStatusBar();
   void readSettings();
   void writeSettings();
   MdiChild *activeMdiChild();
   QMdiSubWindow *findMdiChild(const QString &fileName);
   QMdiArea *mdiArea;
   QSignalMapper *windowMapper;
   QMenu *fileMenu;
   QMenu *editMenu;
   QMenu *windowMenu;
   QMenu *helpMenu;
   QToolBar *fileToolBar;
   QToolBar *editToolBar;
   QAction *newAct;
   QAction *openAct;
   QAction *saveAct;
   QAction *saveAsAct;
   QAction *exitAct;
   QAction *cutAct;
   QAction *copyAct;
   QAction *pasteAct;
   QAction *closeAct;
   QAction *closeAllAct;
   QAction *tileAct;
   QAction *cascadeAct;
   QAction *nextAct;
   QAction *previousAct;
   QAction *separatorAct;
   QAction *aboutAct;
   QAction *aboutQtAct;

};

1. endif

1. include <QtGui>
2. include "mainwindow.h"
3. include "mdichild.h"

MainWindow::MainWindow() {

   mdiArea = new QMdiArea;
   mdiArea->setHorizontalScrollBarPolicy(Qt::ScrollBarAsNeeded);
   mdiArea->setVerticalScrollBarPolicy(Qt::ScrollBarAsNeeded);
   setCentralWidget(mdiArea);
   connect(mdiArea, SIGNAL(subWindowActivated(QMdiSubWindow *)),
           this, SLOT(updateMenus()));
   windowMapper = new QSignalMapper(this);
   connect(windowMapper, SIGNAL(mapped(QWidget *)),
           this, SLOT(setActiveSubWindow(QWidget *)));
   createActions();
   createMenus();
   createToolBars();
   createStatusBar();
   updateMenus();
   readSettings();
   setWindowTitle(tr("MDI"));
   setUnifiedTitleAndToolBarOnMac(true);

} void MainWindow::closeEvent(QCloseEvent *event) {

   mdiArea->closeAllSubWindows();
   if (activeMdiChild()) {
       event->ignore();
   } else {
       writeSettings();
       event->accept();
   }

} void MainWindow::newFile() {

   MdiChild *child = createMdiChild();
   child->newFile();
   child->show();

} void MainWindow::open() {

   QString fileName = QFileDialog::getOpenFileName(this);
   if (!fileName.isEmpty()) {
       QMdiSubWindow *existing = findMdiChild(fileName);
       if (existing) {
           mdiArea->setActiveSubWindow(existing);
           return;
       }
       MdiChild *child = createMdiChild();
       if (child->loadFile(fileName)) {
           statusBar()->showMessage(tr("File loaded"), 2000);
           child->show();
       } else {
           child->close();
       }
   }

} void MainWindow::save() {

   if (activeMdiChild() && activeMdiChild()->save())
       statusBar()->showMessage(tr("File saved"), 2000);

} void MainWindow::saveAs() {

   if (activeMdiChild() && activeMdiChild()->saveAs())
       statusBar()->showMessage(tr("File saved"), 2000);

} void MainWindow::cut() {

   if (activeMdiChild())
       activeMdiChild()->cut();

} void MainWindow::copy() {

   if (activeMdiChild())
       activeMdiChild()->copy();

} void MainWindow::paste() {

   if (activeMdiChild())
       activeMdiChild()->paste();

} void MainWindow::about() {

  QMessageBox::about(this, tr("About MDI"),
           tr("The MDI example demonstrates how to write multiple "
              "document interface applications using Qt."));

} void MainWindow::updateMenus() {

   bool hasMdiChild = (activeMdiChild() != 0);
   saveAct->setEnabled(hasMdiChild);
   saveAsAct->setEnabled(hasMdiChild);
   pasteAct->setEnabled(hasMdiChild);
   closeAct->setEnabled(hasMdiChild);
   closeAllAct->setEnabled(hasMdiChild);
   tileAct->setEnabled(hasMdiChild);
   cascadeAct->setEnabled(hasMdiChild);
   nextAct->setEnabled(hasMdiChild);
   previousAct->setEnabled(hasMdiChild);
   separatorAct->setVisible(hasMdiChild);
   bool hasSelection = (activeMdiChild() &&
                        activeMdiChild()->textCursor().hasSelection());
   cutAct->setEnabled(hasSelection);
   copyAct->setEnabled(hasSelection);

} void MainWindow::updateWindowMenu() {

   windowMenu->clear();
   windowMenu->addAction(closeAct);
   windowMenu->addAction(closeAllAct);
   windowMenu->addSeparator();
   windowMenu->addAction(tileAct);
   windowMenu->addAction(cascadeAct);
   windowMenu->addSeparator();
   windowMenu->addAction(nextAct);
   windowMenu->addAction(previousAct);
   windowMenu->addAction(separatorAct);
   QList<QMdiSubWindow *> windows = mdiArea->subWindowList();
   separatorAct->setVisible(!windows.isEmpty());
   for (int i = 0; i < windows.size(); ++i) {
       MdiChild *child = qobject_cast<MdiChild *>(windows.at(i)->widget());
       QString text;
       if (i < 9) {
           text = tr("&%1 %2").arg(i + 1)
                              .arg(child->userFriendlyCurrentFile());
       } else {
           text = tr("%1 %2").arg(i + 1)
                             .arg(child->userFriendlyCurrentFile());
       }
       QAction *action  = windowMenu->addAction(text);
       action->setCheckable(true);
       action ->setChecked(child == activeMdiChild());
       connect(action, SIGNAL(triggered()), windowMapper, SLOT(map()));
       windowMapper->setMapping(action, windows.at(i));
   }

} MdiChild *MainWindow::createMdiChild() {

   MdiChild *child = new MdiChild;
   mdiArea->addSubWindow(child);
   connect(child, SIGNAL(copyAvailable(bool)),
           cutAct, SLOT(setEnabled(bool)));
   connect(child, SIGNAL(copyAvailable(bool)),
           copyAct, SLOT(setEnabled(bool)));
   return child;

} void MainWindow::createActions() {

   newAct = new QAction(QIcon(":/images/new.png"), tr("&New"), this);
   newAct->setShortcuts(QKeySequence::New);
   newAct->setStatusTip(tr("Create a new file"));
   connect(newAct, SIGNAL(triggered()), this, SLOT(newFile()));
   openAct = new QAction(QIcon(":/images/open.png"), tr("&Open..."), this);
   openAct->setShortcuts(QKeySequence::Open);
   openAct->setStatusTip(tr("Open an existing file"));
   connect(openAct, SIGNAL(triggered()), this, SLOT(open()));
   saveAct = new QAction(QIcon(":/images/save.png"), tr("&Save"), this);
   saveAct->setShortcuts(QKeySequence::Save);
   saveAct->setStatusTip(tr("Save the document to disk"));
   connect(saveAct, SIGNAL(triggered()), this, SLOT(save()));
   saveAsAct = new QAction(tr("Save &As..."), this);
   saveAsAct->setShortcuts(QKeySequence::SaveAs);
   saveAsAct->setStatusTip(tr("Save the document under a new name"));
   connect(saveAsAct, SIGNAL(triggered()), this, SLOT(saveAs()));

   exitAct = new QAction(tr("E&xit"), this);
   exitAct->setShortcut(tr("Ctrl+Q"));
   exitAct->setStatusTip(tr("Exit the application"));
   connect(exitAct, SIGNAL(triggered()), qApp, SLOT(closeAllWindows()));

   cutAct = new QAction(QIcon(":/images/cut.png"), tr("Cu&t"), this);
   cutAct->setShortcuts(QKeySequence::Cut);
   cutAct->setStatusTip(tr("Cut the current selection"s contents to the "
                           "clipboard"));
   connect(cutAct, SIGNAL(triggered()), this, SLOT(cut()));
   copyAct = new QAction(QIcon(":/images/copy.png"), tr("&Copy"), this);
   copyAct->setShortcuts(QKeySequence::Copy);
   copyAct->setStatusTip(tr("Copy the current selection"s contents to the "
                            "clipboard"));
   connect(copyAct, SIGNAL(triggered()), this, SLOT(copy()));
   pasteAct = new QAction(QIcon(":/images/paste.png"), tr("&Paste"), this);
   pasteAct->setShortcuts(QKeySequence::Paste);
   pasteAct->setStatusTip(tr("Paste the clipboard"s contents into the current "
                             "selection"));
   connect(pasteAct, SIGNAL(triggered()), this, SLOT(paste()));
   closeAct = new QAction(tr("Cl&ose"), this);
   closeAct->setShortcut(tr("Ctrl+F4"));
   closeAct->setStatusTip(tr("Close the active window"));
   connect(closeAct, SIGNAL(triggered()),
           mdiArea, SLOT(closeActiveSubWindow()));
   closeAllAct = new QAction(tr("Close &All"), this);
   closeAllAct->setStatusTip(tr("Close all the windows"));
   connect(closeAllAct, SIGNAL(triggered()),
           mdiArea, SLOT(closeAllSubWindows()));
   tileAct = new QAction(tr("&Tile"), this);
   tileAct->setStatusTip(tr("Tile the windows"));
   connect(tileAct, SIGNAL(triggered()), mdiArea, SLOT(tileSubWindows()));
   cascadeAct = new QAction(tr("&Cascade"), this);
   cascadeAct->setStatusTip(tr("Cascade the windows"));
   connect(cascadeAct, SIGNAL(triggered()), mdiArea, SLOT(cascadeSubWindows()));
   nextAct = new QAction(tr("Ne&xt"), this);
   nextAct->setShortcuts(QKeySequence::NextChild);
   nextAct->setStatusTip(tr("Move the focus to the next window"));
   connect(nextAct, SIGNAL(triggered()),
           mdiArea, SLOT(activateNextSubWindow()));
   previousAct = new QAction(tr("Pre&vious"), this);
   previousAct->setShortcuts(QKeySequence::PreviousChild);
   previousAct->setStatusTip(tr("Move the focus to the previous "
                                "window"));
   connect(previousAct, SIGNAL(triggered()),
           mdiArea, SLOT(activatePreviousSubWindow()));
   separatorAct = new QAction(this);
   separatorAct->setSeparator(true);
   aboutAct = new QAction(tr("&About"), this);
   aboutAct->setStatusTip(tr("Show the application"s About box"));
   connect(aboutAct, SIGNAL(triggered()), this, SLOT(about()));
   aboutQtAct = new QAction(tr("About &Qt"), this);
   aboutQtAct->setStatusTip(tr("Show the Qt library"s About box"));
   connect(aboutQtAct, SIGNAL(triggered()), qApp, SLOT(aboutQt()));

} void MainWindow::createMenus() {

   fileMenu = menuBar()->addMenu(tr("&File"));
   fileMenu->addAction(newAct);
   fileMenu->addAction(openAct);
   fileMenu->addAction(saveAct);
   fileMenu->addAction(saveAsAct);
   fileMenu->addSeparator();
   QAction *action = fileMenu->addAction(tr("Switch layout direction"));
   connect(action, SIGNAL(triggered()), this, SLOT(switchLayoutDirection()));
   fileMenu->addAction(exitAct);
   editMenu = menuBar()->addMenu(tr("&Edit"));
   editMenu->addAction(cutAct);
   editMenu->addAction(copyAct);
   editMenu->addAction(pasteAct);
   windowMenu = menuBar()->addMenu(tr("&Window"));
   updateWindowMenu();
   connect(windowMenu, SIGNAL(aboutToShow()), this, SLOT(updateWindowMenu()));
   menuBar()->addSeparator();
   helpMenu = menuBar()->addMenu(tr("&Help"));
   helpMenu->addAction(aboutAct);
   helpMenu->addAction(aboutQtAct);

} void MainWindow::createToolBars() {

   fileToolBar = addToolBar(tr("File"));
   fileToolBar->addAction(newAct);
   fileToolBar->addAction(openAct);
   fileToolBar->addAction(saveAct);
   editToolBar = addToolBar(tr("Edit"));
   editToolBar->addAction(cutAct);
   editToolBar->addAction(copyAct);
   editToolBar->addAction(pasteAct);

} void MainWindow::createStatusBar() {

   statusBar()->showMessage(tr("Ready"));

} void MainWindow::readSettings() {

   QSettings settings("Trolltech", "MDI Example");
   QPoint pos = settings.value("pos", QPoint(200, 200)).toPoint();
   QSize size = settings.value("size", QSize(400, 400)).toSize();
   move(pos);
   resize(size);

} void MainWindow::writeSettings() {

   QSettings settings("Trolltech", "MDI Example");
   settings.setValue("pos", pos());
   settings.setValue("size", size());

} MdiChild *MainWindow::activeMdiChild() {

   if (QMdiSubWindow *activeSubWindow = mdiArea->activeSubWindow())
       return qobject_cast<MdiChild *>(activeSubWindow->widget());
   return 0;

} QMdiSubWindow *MainWindow::findMdiChild(const QString &fileName) {

   QString canonicalFilePath = QFileInfo(fileName).canonicalFilePath();
   foreach (QMdiSubWindow *window, mdiArea->subWindowList()) {
       MdiChild *mdiChild = qobject_cast<MdiChild *>(window->widget());
       if (mdiChild->currentFile() == canonicalFilePath)
           return window;
   }
   return 0;

} void MainWindow::switchLayoutDirection() {

   if (layoutDirection() == Qt::LeftToRight)
       qApp->setLayoutDirection(Qt::RightToLeft);
   else
       qApp->setLayoutDirection(Qt::LeftToRight);

} void MainWindow::setActiveSubWindow(QWidget *window) {

   if (!window)
       return;
   mdiArea->setActiveSubWindow(qobject_cast<QMdiSubWindow *>(window));

}

1. include <QApplication>
2. include "mainwindow.h"

int main(int argc, char *argv[]) {

   Q_INIT_RESOURCE(mdi);
   QApplication app(argc, argv);
   MainWindow mainWin;
   mainWin.show();
   return app.exec();

}

 </source>

Qt SDI window

<source lang="cpp"> /****************************************************************************

• • 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.
  • $QT_END_LICENSE$
  • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • /

1. ifndef MAINWINDOW_H
2. define MAINWINDOW_H
3. include <QMainWindow>

QT_BEGIN_NAMESPACE class QAction; class QMenu; class QTextEdit; QT_END_NAMESPACE class MainWindow : public QMainWindow {

   Q_OBJECT

public:

   MainWindow();
   MainWindow(const QString &fileName);

protected:

   void closeEvent(QCloseEvent *event);

private slots:

   void newFile();
   void open();
   bool save();
   bool saveAs();
   void about();
   void documentWasModified();

private:

   void init();
   void createActions();
   void createMenus();
   void createToolBars();
   void createStatusBar();
   void readSettings();
   void writeSettings();
   bool maybeSave();
   void loadFile(const QString &fileName);
   bool saveFile(const QString &fileName);
   void setCurrentFile(const QString &fileName);
   QString strippedName(const QString &fullFileName);
   MainWindow *findMainWindow(const QString &fileName);
   QTextEdit *textEdit;
   QString curFile;
   bool isUntitled;
   QMenu *fileMenu;
   QMenu *editMenu;
   QMenu *helpMenu;
   QToolBar *fileToolBar;
   QToolBar *editToolBar;
   QAction *newAct;
   QAction *openAct;
   QAction *saveAct;
   QAction *saveAsAct;
   QAction *closeAct;
   QAction *exitAct;
   QAction *cutAct;
   QAction *copyAct;
   QAction *pasteAct;
   QAction *aboutAct;
   QAction *aboutQtAct;

};

1. endif

1. include <QtGui>
2. include "mainwindow.h"

MainWindow::MainWindow() {

   init();
   setCurrentFile("");

} MainWindow::MainWindow(const QString &fileName) {

   init();
   loadFile(fileName);

} void MainWindow::closeEvent(QCloseEvent *event) {

   if (maybeSave()) {
       writeSettings();
       event->accept();
   } else {
       event->ignore();
   }

} void MainWindow::newFile() {

   MainWindow *other = new MainWindow;
   other->move(x() + 40, y() + 40);
   other->show();

} void MainWindow::open() {

   QString fileName = QFileDialog::getOpenFileName(this);
   if (!fileName.isEmpty()) {
       MainWindow *existing = findMainWindow(fileName);
       if (existing) {
           existing->show();
           existing->raise();
           existing->activateWindow();
           return;
       }
       if (isUntitled && textEdit->document()->isEmpty()
               && !isWindowModified()) {
           loadFile(fileName);
       } else {
           MainWindow *other = new MainWindow(fileName);
           if (other->isUntitled) {
               delete other;
               return;
           }
           other->move(x() + 40, y() + 40);
           other->show();
       }
   }

} bool MainWindow::save() {

   if (isUntitled) {
       return saveAs();
   } else {
       return saveFile(curFile);
   }

} bool MainWindow::saveAs() {

   QString fileName = QFileDialog::getSaveFileName(this, tr("Save As"),
                                                   curFile);
   if (fileName.isEmpty())
       return false;
   return saveFile(fileName);

} void MainWindow::about() {

  QMessageBox::about(this, tr("About SDI"),
           tr("The SDI example demonstrates how to write single "
              "document interface applications using Qt."));

} void MainWindow::documentWasModified() {

   setWindowModified(true);

} void MainWindow::init() {

   setAttribute(Qt::WA_DeleteOnClose);
   isUntitled = true;
   textEdit = new QTextEdit;
   setCentralWidget(textEdit);
   createActions();
   createMenus();
   createToolBars();
   createStatusBar();
   readSettings();
   connect(textEdit->document(), SIGNAL(contentsChanged()),
           this, SLOT(documentWasModified()));
   setUnifiedTitleAndToolBarOnMac(true);

} void MainWindow::createActions() {

   newAct = new QAction(QIcon(":/images/new.png"), tr("&New"), this);
   newAct->setShortcuts(QKeySequence::New);
   newAct->setStatusTip(tr("Create a new file"));
   connect(newAct, SIGNAL(triggered()), this, SLOT(newFile()));
   openAct = new QAction(QIcon(":/images/open.png"), tr("&Open..."), this);
   openAct->setShortcuts(QKeySequence::Open);
   openAct->setStatusTip(tr("Open an existing file"));
   connect(openAct, SIGNAL(triggered()), this, SLOT(open()));
   saveAct = new QAction(QIcon(":/images/save.png"), tr("&Save"), this);
   saveAct->setShortcuts(QKeySequence::Save);
   saveAct->setStatusTip(tr("Save the document to disk"));
   connect(saveAct, SIGNAL(triggered()), this, SLOT(save()));
   saveAsAct = new QAction(tr("Save &As..."), this);
   saveAsAct->setShortcuts(QKeySequence::SaveAs);
   saveAsAct->setStatusTip(tr("Save the document under a new name"));
   connect(saveAsAct, SIGNAL(triggered()), this, SLOT(saveAs()));
   closeAct = new QAction(tr("&Close"), this);
   closeAct->setShortcut(tr("Ctrl+W"));
   closeAct->setStatusTip(tr("Close this window"));
   connect(closeAct, SIGNAL(triggered()), this, SLOT(close()));
   exitAct = new QAction(tr("E&xit"), this);
   exitAct->setShortcut(tr("Ctrl+Q"));
   exitAct->setStatusTip(tr("Exit the application"));
   connect(exitAct, SIGNAL(triggered()), qApp, SLOT(closeAllWindows()));
   cutAct = new QAction(QIcon(":/images/cut.png"), tr("Cu&t"), this);
   cutAct->setShortcuts(QKeySequence::Cut);
   cutAct->setStatusTip(tr("Cut the current selection"s contents to the "
                           "clipboard"));
   connect(cutAct, SIGNAL(triggered()), textEdit, SLOT(cut()));
   copyAct = new QAction(QIcon(":/images/copy.png"), tr("&Copy"), this);
   copyAct->setShortcuts(QKeySequence::Copy);
   copyAct->setStatusTip(tr("Copy the current selection"s contents to the "
                            "clipboard"));
   connect(copyAct, SIGNAL(triggered()), textEdit, SLOT(copy()));
   pasteAct = new QAction(QIcon(":/images/paste.png"), tr("&Paste"), this);
   pasteAct->setShortcuts(QKeySequence::Paste);
   pasteAct->setStatusTip(tr("Paste the clipboard"s contents into the current "
                             "selection"));
   connect(pasteAct, SIGNAL(triggered()), textEdit, SLOT(paste()));
   aboutAct = new QAction(tr("&About"), this);
   aboutAct->setStatusTip(tr("Show the application"s About box"));
   connect(aboutAct, SIGNAL(triggered()), this, SLOT(about()));
   aboutQtAct = new QAction(tr("About &Qt"), this);
   aboutQtAct->setStatusTip(tr("Show the Qt library"s About box"));
   connect(aboutQtAct, SIGNAL(triggered()), qApp, SLOT(aboutQt()));

   cutAct->setEnabled(false);
   copyAct->setEnabled(false);
   connect(textEdit, SIGNAL(copyAvailable(bool)),
           cutAct, SLOT(setEnabled(bool)));
   connect(textEdit, SIGNAL(copyAvailable(bool)),
           copyAct, SLOT(setEnabled(bool)));

} //! [implicit tr context] void MainWindow::createMenus() {

   fileMenu = menuBar()->addMenu(tr("&File"));

//! [implicit tr context]

   fileMenu->addAction(newAct);
   fileMenu->addAction(openAct);
   fileMenu->addAction(saveAct);
   fileMenu->addAction(saveAsAct);
   fileMenu->addSeparator();
   fileMenu->addAction(closeAct);
   fileMenu->addAction(exitAct);
   editMenu = menuBar()->addMenu(tr("&Edit"));
   editMenu->addAction(cutAct);
   editMenu->addAction(copyAct);
   editMenu->addAction(pasteAct);
   menuBar()->addSeparator();
   helpMenu = menuBar()->addMenu(tr("&Help"));
   helpMenu->addAction(aboutAct);
   helpMenu->addAction(aboutQtAct);

} void MainWindow::createToolBars() {

   fileToolBar = addToolBar(tr("File"));
   fileToolBar->addAction(newAct);
   fileToolBar->addAction(openAct);
   fileToolBar->addAction(saveAct);
   editToolBar = addToolBar(tr("Edit"));
   editToolBar->addAction(cutAct);
   editToolBar->addAction(copyAct);
   editToolBar->addAction(pasteAct);

} void MainWindow::createStatusBar() {

   statusBar()->showMessage(tr("Ready"));

} void MainWindow::readSettings() {

   QSettings settings("Trolltech", "SDI Example");
   QPoint pos = settings.value("pos", QPoint(200, 200)).toPoint();
   QSize size = settings.value("size", QSize(400, 400)).toSize();
   move(pos);
   resize(size);

} void MainWindow::writeSettings() {

   QSettings settings("Trolltech", "SDI Example");
   settings.setValue("pos", pos());
   settings.setValue("size", size());

} bool MainWindow::maybeSave() {

   if (textEdit->document()->isModified()) {
 QMessageBox::StandardButton ret;
       ret = QMessageBox::warning(this, tr("SDI"),
                    tr("The document has been modified.\n"
                       "Do you want to save your changes?"),
                    QMessageBox::Save | QMessageBox::Discard
        | QMessageBox::Cancel);
       if (ret == QMessageBox::Save)
           return save();
       else if (ret == QMessageBox::Cancel)
           return false;
   }
   return true;

} void MainWindow::loadFile(const QString &fileName) {

   QFile file(fileName);
   if (!file.open(QFile::ReadOnly | QFile::Text)) {
       QMessageBox::warning(this, tr("SDI"),
                            tr("Cannot read file %1:\n%2.")
                            .arg(fileName)
                            .arg(file.errorString()));
       return;
   }
   QTextStream in(&file);
   QApplication::setOverrideCursor(Qt::WaitCursor);
   textEdit->setPlainText(in.readAll());
   QApplication::restoreOverrideCursor();
   setCurrentFile(fileName);
   statusBar()->showMessage(tr("File loaded"), 2000);

} bool MainWindow::saveFile(const QString &fileName) {

   QFile file(fileName);
   if (!file.open(QFile::WriteOnly | QFile::Text)) {
       QMessageBox::warning(this, tr("SDI"),
                            tr("Cannot write file %1:\n%2.")
                            .arg(fileName)
                            .arg(file.errorString()));
       return false;
   }
   QTextStream out(&file);
   QApplication::setOverrideCursor(Qt::WaitCursor);
   out << textEdit->toPlainText();
   QApplication::restoreOverrideCursor();
   setCurrentFile(fileName);
   statusBar()->showMessage(tr("File saved"), 2000);
   return true;

} void MainWindow::setCurrentFile(const QString &fileName) {

   static int sequenceNumber = 1;
   isUntitled = fileName.isEmpty();
   if (isUntitled) {
       curFile = tr("document%1.txt").arg(sequenceNumber++);
   } else {
       curFile = QFileInfo(fileName).canonicalFilePath();
   }
   textEdit->document()->setModified(false);
   setWindowModified(false);
   setWindowTitle(tr("%1[*] - %2").arg(strippedName(curFile))
                                      .arg(tr("SDI")));

} QString MainWindow::strippedName(const QString &fullFileName) {

   return QFileInfo(fullFileName).fileName();

} MainWindow *MainWindow::findMainWindow(const QString &fileName) {

   QString canonicalFilePath = QFileInfo(fileName).canonicalFilePath();
   foreach (QWidget *widget, qApp->topLevelWidgets()) {
       MainWindow *mainWin = qobject_cast<MainWindow *>(widget);
       if (mainWin && mainWin->curFile == canonicalFilePath)
           return mainWin;
   }
   return 0;

}

1. include <QApplication>
2. include "mainwindow.h"

int main(int argc, char *argv[]) {

   Q_INIT_RESOURCE(sdi);
   QApplication app(argc, argv);
   MainWindow *mainWin = new MainWindow;
   mainWin->show();
   return app.exec();

}

 </source>

SdiWindow based text editor

<source lang="cpp">

Foundations of Qt Development\Chapter04\dock\infowidget.cpp /*

* Copyright (c) 2006-2007, Johan Thelin
* 
* All rights reserved.
* 
* 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 APress 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, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
*/

1. include "infowidget.h"

InfoWidget::InfoWidget( QWidget *parent ) : QLabel( parent ) {

 setAlignment( Qt::AlignCenter );
 setWordWrap( true );
 
 setText( tr("Ready") );

}

void InfoWidget::documentChanged( int position, int charsRemoved, int charsAdded ) {

 QString text;
 
 if( charsRemoved )
   text = tr("%1 removed").arg( charsRemoved );
   
 if( charsRemoved && charsAdded )
   text += tr(", ");
   
 if( charsAdded )
   text += tr("%1 added").arg( charsAdded );
   
 setText( text );

}

Foundations of Qt Development\Chapter04\dock\infowidget.h /*

* Copyright (c) 2006-2007, Johan Thelin
* 
* All rights reserved.
* 
* 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 APress 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, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
*/

1. ifndef INFOWIDGET_H
2. define INFOWIDGET_H
3. include <QLabel>

class InfoWidget : public QLabel {

 Q_OBJECT

public:

 InfoWidget( QWidget *parent=0 );
 

public slots:

 void documentChanged( int position, int charsRemoved, int charsAdded );

};

1. endif // INFOWIDGET_H

Foundations of Qt Development\Chapter04\dock\main.cpp /*

* Copyright (c) 2006-2007, Johan Thelin
* 
* All rights reserved.
* 
* 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 APress 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, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
*/

1. include <QApplication>
2. include "sdiwindow.h"

int main( int argc, char **argv ) {

 QApplication app( argc, argv );
 
 (new SdiWindow)->show();
 
 return app.exec();

}

Foundations of Qt Development\Chapter04\dock\sdiwindow.cpp /*

* Copyright (c) 2006-2007, Johan Thelin
* 
* All rights reserved.
* 
* 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 APress 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, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
*/

1. include <QApplication>
2. include <QMenuBar>
3. include <QToolBar>
4. include <QStatusBar>
5. include <QCloseEvent>
6. include <QMessageBox>
7. include <QTextEdit>
8. include <QDockWidget>
9. include "infowidget.h"
10. include "sdiwindow.h"

SdiWindow::SdiWindow( QWidget *parent ) : QMainWindow( parent ) {

 setAttribute( Qt::WA_DeleteOnClose );
 setWindowTitle( tr("%1[*] - %2" ).arg(tr("unnamed")).arg(tr("SDI")) );
 docWidget = new QTextEdit( this );
 setCentralWidget( docWidget );
 connect( docWidget->document(), SIGNAL(modificationChanged(bool)), this, SLOT(setWindowModified(bool)) );
 
 createDocks();
 createActions();
 createMenus();
 createToolbars();
 statusBar()->showMessage( tr("Done") );

} void SdiWindow::createDocks() {

 dock = new QDockWidget( tr("Information"), this );
 InfoWidget *info = new InfoWidget( dock );
 dock->setWidget( info );
 addDockWidget( Qt::LeftDockWidgetArea, dock );
 
 connect( docWidget->document(), SIGNAL(contentsChange(int, int, int)), info, SLOT(documentChanged(int, int, int)) );

}

void SdiWindow::closeEvent( QCloseEvent *event ) {

 if( isSafeToClose() )
   event->accept();
 else
   event->ignore();

} bool SdiWindow::isSafeToClose() {

 if( isWindowModified() ) 
 {
   switch( QMessageBox::warning( this, tr("SDI"), 
     tr("The document has unsaved changes.\n"
        "Do you want to save it before it is closed?"), 
        QMessageBox::Discard | QMessageBox::Cancel ) )
   {
   case QMessageBox::Cancel:
     return false;
   default:
     return true;
   }
 }
 return true;

}

void SdiWindow::fileNew() {

 (new SdiWindow())->show();

} void SdiWindow::helpAbout() {

 QMessageBox::about( this, tr("About SDI"), tr("A single document interface application.") );

} void SdiWindow::createActions() {

 newAction = new QAction( QIcon(":/images/new.png"), tr("&New"), this );
 newAction->setShortcut( tr("Ctrl+N") );
 newAction->setStatusTip( tr("Create a new document") );
 connect( newAction, SIGNAL(triggered()), this, SLOT(fileNew()) );
 closeAction = new QAction( tr("&Close"), this );
 closeAction->setShortcut( tr("Ctrl+W") );
 closeAction->setStatusTip( tr("Close this document") );
 connect( closeAction, SIGNAL(triggered()), this, SLOT(close()) );
 exitAction = new QAction( tr("E&xit"), this );
 exitAction->setShortcut( tr("Ctrl+Q") );
 exitAction->setStatusTip( tr("Quit the application") );
 connect( exitAction, SIGNAL(triggered()), qApp, SLOT(closeAllWindows()) );
 
 cutAction = new QAction( QIcon(":/images/cut.png"), tr("Cu&t"), this );
 cutAction->setShortcut( tr("Ctrl+X") );
 cutAction->setStatusTip( tr("Cut") );
 cutAction->setEnabled(false);
 connect( docWidget, SIGNAL(copyAvailable(bool)), cutAction, SLOT(setEnabled(bool)) );
 connect( cutAction, SIGNAL(triggered()), docWidget, SLOT(cut()) );
 
 copyAction = new QAction( QIcon(":/images/copy.png"), tr("&Copy"), this );
 copyAction->setShortcut( tr("Ctrl+C") );
 copyAction->setStatusTip( tr("Copy") );
 copyAction->setEnabled(false);
 connect( docWidget, SIGNAL(copyAvailable(bool)), copyAction, SLOT(setEnabled(bool)) );
 connect( copyAction, SIGNAL(triggered()), docWidget, SLOT(copy()) );
 pasteAction = new QAction( QIcon(":/images/paste.png"), tr("&Paste"), this );
 pasteAction->setShortcut( tr("Ctrl+V") );
 pasteAction->setStatusTip( tr("Paste") );
 connect( pasteAction, SIGNAL(triggered()), docWidget, SLOT(paste()) );
 
 aboutAction = new QAction( tr("&About"), this );
 aboutAction->setStatusTip( tr("About this application") );
 connect( aboutAction, SIGNAL(triggered()), this, SLOT(helpAbout()) );
 aboutQtAction = new QAction( tr("About &Qt"), this );
 aboutQtAction->setStatusTip( tr("About the Qt toolkit") );
 connect( aboutQtAction, SIGNAL(triggered()), qApp, SLOT(aboutQt()) );

} void SdiWindow::createMenus() {

 QMenu *menu;
 
 menu = menuBar()->addMenu( tr("&File") );
 menu->addAction( newAction );
 menu->addAction( closeAction );
 menu->addSeparator();
 menu->addAction( exitAction );
 
 menu = menuBar()->addMenu( tr("&Edit") );
 menu->addAction( cutAction );
 menu->addAction( copyAction );
 menu->addAction( pasteAction );
 
 menu = menuBar()->addMenu( tr("&View") );
 menu->addAction( dock->toggleViewAction() );
 menu = menuBar()->addMenu( tr("&Help") );
 menu->addAction( aboutAction );
 menu->addAction( aboutQtAction );

} void SdiWindow::createToolbars() {

 QToolBar *toolbar;
 
 toolbar = addToolBar( tr("File") );
 toolbar->addAction( newAction );
 
 toolbar = addToolBar( tr("Edit") );
 toolbar->addAction( cutAction );
 toolbar->addAction( copyAction );
 toolbar->addAction( pasteAction );

}

Foundations of Qt Development\Chapter04\dock\sdiwindow.h /*

* Copyright (c) 2006-2007, Johan Thelin
* 
* All rights reserved.
* 
* 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 APress 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, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
*/

1. ifndef SDIWINDOW_H
2. define SDIWINDOW_H
3. include <QMainWindow>

class QAction; class QTextEdit; class QDockWidget; class SdiWindow : public QMainWindow {

 Q_OBJECT
 

public:

 SdiWindow( QWidget *parent = 0 );
 

protected:

 void closeEvent( QCloseEvent *event );
 

private slots:

 void fileNew();
 void helpAbout();

private:

 void createDocks();
 void createActions();
 void createMenus();
 void createToolbars();
 bool isSafeToClose();
 QTextEdit *docWidget;
 
 QAction *newAction;
 QAction *closeAction;
 QAction *exitAction;
 
 QAction *cutAction;
 QAction *copyAction;
 QAction *pasteAction;
 
 QAction *aboutAction;
 QAction *aboutQtAction;
 
 QDockWidget *dock;

};

1. endif // SDIWINDOW_H

 </source>

Top level window

<source lang="cpp"> /****************************************************************************

• • 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 documentation 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.
  • $QT_END_LICENSE$
  • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • /

1. include <QtGui>

int main(int argc, char *argv[]) {

   QApplication app(argc, argv);

//! [create, resize and show]

   QWidget *window = new QWidget();
   window->resize(320, 240);
   window->show();

//! [create, resize and show]

   window->setWindowTitle(tr("Top-level widget"));
   return app.exec();

}

 </source>

Window style flags

<source lang="cpp"> /****************************************************************************

• • 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.
  • $QT_END_LICENSE$
  • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • /

1. ifndef CONTROLLERWINDOW_H
2. define CONTROLLERWINDOW_H
3. include <QWidget>
4. include "previewwindow.h"

QT_BEGIN_NAMESPACE class QCheckBox; class QGroupBox; class QLabel; class QPushButton; class QRadioButton; QT_END_NAMESPACE

class ControllerWindow : public QWidget {

   Q_OBJECT

public:

   ControllerWindow();

private slots:

   void updatePreview();

private:

   void createTypeGroupBox();
   void createHintsGroupBox();
   QCheckBox *createCheckBox(const QString &text);
   QRadioButton *createRadioButton(const QString &text);
   PreviewWindow *previewWindow;
   QGroupBox *typeGroupBox;
   QGroupBox *hintsGroupBox;
   QPushButton *quitButton;
   QRadioButton *windowRadioButton;
   QRadioButton *dialogRadioButton;
   QRadioButton *sheetRadioButton;
   QRadioButton *drawerRadioButton;
   QRadioButton *popupRadioButton;
   QRadioButton *toolRadioButton;
   QRadioButton *toolTipRadioButton;
   QRadioButton *splashScreenRadioButton;
   QCheckBox *msWindowsFixedSizeDialogCheckBox;
   QCheckBox *x11BypassWindowManagerCheckBox;
   QCheckBox *framelessWindowCheckBox;
   QCheckBox *windowTitleCheckBox;
   QCheckBox *windowSystemMenuCheckBox;
   QCheckBox *windowMinimizeButtonCheckBox;
   QCheckBox *windowMaximizeButtonCheckBox;
   QCheckBox *windowCloseButtonCheckBox;
   QCheckBox *windowContextHelpButtonCheckBox;
   QCheckBox *windowShadeButtonCheckBox;
   QCheckBox *windowStaysOnTopCheckBox;
   QCheckBox *windowStaysOnBottomCheckBox;
   QCheckBox *customizeWindowHintCheckBox;

};

1. endif

1. include <QtGui>
2. include "controllerwindow.h"

ControllerWindow::ControllerWindow() {

   previewWindow = new PreviewWindow(this);
   createTypeGroupBox();
   createHintsGroupBox();
   quitButton = new QPushButton(tr("&Quit"));
   connect(quitButton, SIGNAL(clicked()), qApp, SLOT(quit()));
   QHBoxLayout *bottomLayout = new QHBoxLayout;
   bottomLayout->addStretch();
   bottomLayout->addWidget(quitButton);
   QVBoxLayout *mainLayout = new QVBoxLayout;
   mainLayout->addWidget(typeGroupBox);
   mainLayout->addWidget(hintsGroupBox);
   mainLayout->addLayout(bottomLayout);
   setLayout(mainLayout);
   setWindowTitle(tr("Window Flags"));
   updatePreview();

}

void ControllerWindow::updatePreview() {

   Qt::WindowFlags flags = 0;
   if (windowRadioButton->isChecked()) {
       flags = Qt::Window;
   } else if (dialogRadioButton->isChecked()) {
       flags = Qt::Dialog;
   } else if (sheetRadioButton->isChecked()) {
       flags = Qt::Sheet;
   } else if (drawerRadioButton->isChecked()) {
       flags = Qt::Drawer;
   } else if (popupRadioButton->isChecked()) {
       flags = Qt::Popup;
   } else if (toolRadioButton->isChecked()) {
       flags = Qt::Tool;
   } else if (toolTipRadioButton->isChecked()) {
       flags = Qt::ToolTip;
   } else if (splashScreenRadioButton->isChecked()) {
       flags = Qt::SplashScreen;

   }

   if (msWindowsFixedSizeDialogCheckBox->isChecked())
       flags |= Qt::MSWindowsFixedSizeDialogHint;
   if (x11BypassWindowManagerCheckBox->isChecked())
       flags |= Qt::X11BypassWindowManagerHint;
   if (framelessWindowCheckBox->isChecked())
       flags |= Qt::FramelessWindowHint;
   if (windowTitleCheckBox->isChecked())
       flags |= Qt::WindowTitleHint;
   if (windowSystemMenuCheckBox->isChecked())
       flags |= Qt::WindowSystemMenuHint;
   if (windowMinimizeButtonCheckBox->isChecked())
       flags |= Qt::WindowMinimizeButtonHint;
   if (windowMaximizeButtonCheckBox->isChecked())
       flags |= Qt::WindowMaximizeButtonHint;
   if (windowCloseButtonCheckBox->isChecked())
       flags |= Qt::WindowCloseButtonHint;
   if (windowContextHelpButtonCheckBox->isChecked())
       flags |= Qt::WindowContextHelpButtonHint;
   if (windowShadeButtonCheckBox->isChecked())
       flags |= Qt::WindowShadeButtonHint;
   if (windowStaysOnTopCheckBox->isChecked())
       flags |= Qt::WindowStaysOnTopHint;
   if (windowStaysOnBottomCheckBox->isChecked())
       flags |= Qt::WindowStaysOnBottomHint;
   if (customizeWindowHintCheckBox->isChecked())
       flags |= Qt::CustomizeWindowHint;
   previewWindow->setWindowFlags(flags);

   QPoint pos = previewWindow->pos();
   if (pos.x() < 0)
       pos.setX(0);
   if (pos.y() < 0)
       pos.setY(0);
   previewWindow->move(pos);
   previewWindow->show();

}

void ControllerWindow::createTypeGroupBox() {

   typeGroupBox = new QGroupBox(tr("Type"));
   windowRadioButton = createRadioButton(tr("Window"));
   dialogRadioButton = createRadioButton(tr("Dialog"));
   sheetRadioButton = createRadioButton(tr("Sheet"));
   drawerRadioButton = createRadioButton(tr("Drawer"));
   popupRadioButton = createRadioButton(tr("Popup"));
   toolRadioButton = createRadioButton(tr("Tool"));
   toolTipRadioButton = createRadioButton(tr("Tooltip"));
   splashScreenRadioButton = createRadioButton(tr("Splash screen"));
   windowRadioButton->setChecked(true);
   QGridLayout *layout = new QGridLayout;
   layout->addWidget(windowRadioButton, 0, 0);
   layout->addWidget(dialogRadioButton, 1, 0);
   layout->addWidget(sheetRadioButton, 2, 0);
   layout->addWidget(drawerRadioButton, 3, 0);
   layout->addWidget(popupRadioButton, 0, 1);
   layout->addWidget(toolRadioButton, 1, 1);
   layout->addWidget(toolTipRadioButton, 2, 1);
   layout->addWidget(splashScreenRadioButton, 3, 1);
   typeGroupBox->setLayout(layout);

}

void ControllerWindow::createHintsGroupBox() {

   hintsGroupBox = new QGroupBox(tr("Hints"));
   msWindowsFixedSizeDialogCheckBox =
           createCheckBox(tr("MS Windows fixed size dialog"));
   x11BypassWindowManagerCheckBox =
           createCheckBox(tr("X11 bypass window manager"));
   framelessWindowCheckBox = createCheckBox(tr("Frameless window"));
   windowTitleCheckBox = createCheckBox(tr("Window title"));
   windowSystemMenuCheckBox = createCheckBox(tr("Window system menu"));
   windowMinimizeButtonCheckBox = createCheckBox(tr("Window minimize button"));
   windowMaximizeButtonCheckBox = createCheckBox(tr("Window maximize button"));
   windowCloseButtonCheckBox = createCheckBox(tr("Window close button"));
   windowContextHelpButtonCheckBox =
           createCheckBox(tr("Window context help button"));
   windowShadeButtonCheckBox = createCheckBox(tr("Window shade button"));
   windowStaysOnTopCheckBox = createCheckBox(tr("Window stays on top"));
   windowStaysOnBottomCheckBox = createCheckBox(tr("Window stays on bottom"));
   customizeWindowHintCheckBox= createCheckBox(tr("Customize window"));
   QGridLayout *layout = new QGridLayout;
   layout->addWidget(msWindowsFixedSizeDialogCheckBox, 0, 0);
   layout->addWidget(x11BypassWindowManagerCheckBox, 1, 0);
   layout->addWidget(framelessWindowCheckBox, 2, 0);
   layout->addWidget(windowTitleCheckBox, 3, 0);
   layout->addWidget(windowSystemMenuCheckBox, 4, 0);
   layout->addWidget(windowMinimizeButtonCheckBox, 0, 1);
   layout->addWidget(windowMaximizeButtonCheckBox, 1, 1);
   layout->addWidget(windowCloseButtonCheckBox, 2, 1);
   layout->addWidget(windowContextHelpButtonCheckBox, 3, 1);
   layout->addWidget(windowShadeButtonCheckBox, 4, 1);
   layout->addWidget(windowStaysOnTopCheckBox, 5, 1);
   layout->addWidget(windowStaysOnBottomCheckBox, 6, 1);
   layout->addWidget(customizeWindowHintCheckBox, 5, 0);
   hintsGroupBox->setLayout(layout);

}

QCheckBox *ControllerWindow::createCheckBox(const QString &text) {

   QCheckBox *checkBox = new QCheckBox(text);
   connect(checkBox, SIGNAL(clicked()), this, SLOT(updatePreview()));
   return checkBox;

}

QRadioButton *ControllerWindow::createRadioButton(const QString &text) {

   QRadioButton *button = new QRadioButton(text);
   connect(button, SIGNAL(clicked()), this, SLOT(updatePreview()));
   return button;

}

1. ifndef PREVIEWWINDOW_H
2. define PREVIEWWINDOW_H
3. include <QWidget>

QT_BEGIN_NAMESPACE class QPushButton; class QTextEdit; QT_END_NAMESPACE

class PreviewWindow : public QWidget {

   Q_OBJECT

public:

   PreviewWindow(QWidget *parent = 0);
   void setWindowFlags(Qt::WindowFlags flags);

private:

   QTextEdit *textEdit;
   QPushButton *closeButton;

};

1. endif

1. include <QtGui>
2. include "previewwindow.h"

PreviewWindow::PreviewWindow(QWidget *parent)

   : QWidget(parent)

{

   textEdit = new QTextEdit;
   textEdit->setReadOnly(true);
   textEdit->setLineWrapMode(QTextEdit::NoWrap);
   closeButton = new QPushButton(tr("&Close"));
   connect(closeButton, SIGNAL(clicked()), this, SLOT(close()));
   QVBoxLayout *layout = new QVBoxLayout;
   layout->addWidget(textEdit);
   layout->addWidget(closeButton);
   setLayout(layout);
   setWindowTitle(tr("Preview"));

}

void PreviewWindow::setWindowFlags(Qt::WindowFlags flags) {

   QWidget::setWindowFlags(flags);
   QString text;
   Qt::WindowFlags type = (flags & Qt::WindowType_Mask);
   if (type == Qt::Window) {
       text = "Qt::Window";
   } else if (type == Qt::Dialog) {
       text = "Qt::Dialog";
   } else if (type == Qt::Sheet) {
       text = "Qt::Sheet";
   } else if (type == Qt::Drawer) {
       text = "Qt::Drawer";
   } else if (type == Qt::Popup) {
       text = "Qt::Popup";
   } else if (type == Qt::Tool) {
       text = "Qt::Tool";
   } else if (type == Qt::ToolTip) {
       text = "Qt::ToolTip";
   } else if (type == Qt::SplashScreen) {
       text = "Qt::SplashScreen";
   }
   if (flags & Qt::MSWindowsFixedSizeDialogHint)
       text += "\n| Qt::MSWindowsFixedSizeDialogHint";
   if (flags & Qt::X11BypassWindowManagerHint)
       text += "\n| Qt::X11BypassWindowManagerHint";
   if (flags & Qt::FramelessWindowHint)
       text += "\n| Qt::FramelessWindowHint";
   if (flags & Qt::WindowTitleHint)
       text += "\n| Qt::WindowTitleHint";
   if (flags & Qt::WindowSystemMenuHint)
       text += "\n| Qt::WindowSystemMenuHint";
   if (flags & Qt::WindowMinimizeButtonHint)
       text += "\n| Qt::WindowMinimizeButtonHint";
   if (flags & Qt::WindowMaximizeButtonHint)
       text += "\n| Qt::WindowMaximizeButtonHint";
   if (flags & Qt::WindowCloseButtonHint)
       text += "\n| Qt::WindowCloseButtonHint";
   if (flags & Qt::WindowContextHelpButtonHint)
       text += "\n| Qt::WindowContextHelpButtonHint";
   if (flags & Qt::WindowShadeButtonHint)
       text += "\n| Qt::WindowShadeButtonHint";
   if (flags & Qt::WindowStaysOnTopHint)
       text += "\n| Qt::WindowStaysOnTopHint";
   if (flags & Qt::CustomizeWindowHint)
       text += "\n| Qt::CustomizeWindowHint";
   textEdit->setPlainText(text);

}

1. include <QApplication>
2. include "controllerwindow.h"

int main(int argc, char *argv[]) {

   QApplication app(argc, argv);
   ControllerWindow controller;
   controller.show();
   return app.exec();

}

 </source>