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Link QAction and button

<source lang="cpp"> Foundations of Qt Development\Chapter04\sdi\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\sdi\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 "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)) );
 
 createActions();
 createMenus();
 createToolbars();
 statusBar()->showMessage( tr("Done") );

}

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("&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\sdi\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 SdiWindow : public QMainWindow {

 Q_OBJECT
 

public:

 SdiWindow( QWidget *parent = 0 );
 

protected:

 void closeEvent( QCloseEvent *event );
 

private slots:

 void fileNew();
 void helpAbout();

private:

 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;

};

  1. endif // SDIWINDOW_H


 </source>


QAction with shortcut

<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>

class MainWindow : public QMainWindow { public:

   MainWindow();
   QAction *newAct;

}; MainWindow() {

   newAct = new QAction(tr("&New"), this);
   newAct->setShortcut(tr("Ctrl+N"));
   newAct->setStatusTip(tr("Create a new file"));
   newAct->setWhatsThis(tr("Click this option to create a new file."));

} int main() {

   return 0;

}


 </source>


Set up Menu bar with QAction

<source lang="cpp"> Foundations of Qt Development\Chapter08\readwriteapplication\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();
 QObject::connect( &app, SIGNAL(lastWindowClosed()), &app, SLOT(quit()) );
 
 return app.exec();

}

Foundations of Qt Development\Chapter08\readwriteapplication\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 <QFile>
  9. include <QTextStream>
  10. include <QFileDialog>
  11. 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)) );
 
 createActions();
 createMenus();
 createToolbars();
 statusBar()->showMessage( tr("Done") );

}

void SdiWindow::closeEvent( QCloseEvent *event ) {

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

}

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()) );
 openAction = new QAction( tr("&Open"), this );
 openAction->setShortcut( tr("Ctrl+O") );
 openAction->setStatusTip( tr("Open a document") );
 connect( openAction, SIGNAL(triggered()), this, SLOT(fileOpen()) );

 saveAction = new QAction( tr("&Save"), this );
 saveAction->setShortcut( tr("Ctrl+S") );
 saveAction->setStatusTip( tr("Save the document") );
 connect( saveAction, SIGNAL(triggered()), this, SLOT(fileSave()) );

 saveAsAction = new QAction( tr("Save &As"), this );
 saveAsAction->setStatusTip( tr("Save the document as") );
 connect( saveAsAction, SIGNAL(triggered()), this, SLOT(fileSaveAs()) );

 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->addSeparator();
 menu->addAction( openAction );
 menu->addAction( saveAction );
 menu->addAction( saveAsAction );
 menu->addSeparator();
 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("&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 );

}

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::Save | QMessageBox::Discard | QMessageBox::Cancel ) )
   {
   case QMessageBox::Cancel:
     return false;
   case QMessageBox::Save:
     return fileSave();
   default:
     return true;
   }
 }
 return true;

} void SdiWindow::fileOpen() {

 QString filename = QFileDialog::getOpenFileName( this );
 if( filename.isEmpty() )
   return;
 if( currentFilename.isEmpty() && !docWidget->document()->isModified() )
   loadFile( filename );
 else
 {    
   SdiWindow *window = new SdiWindow();
   window->loadFile( filename );
   window->show();
 }

} bool SdiWindow::fileSave() {

 if( currentFilename.isEmpty() )
   return fileSaveAs();
 else
   return saveFile( currentFilename );  

} bool SdiWindow::fileSaveAs() {

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

} bool SdiWindow::saveFile( QString filename ) {

 QFile file( filename );
 if( !file.open( QIODevice::WriteOnly | QIODevice::Text ) )
 {
   QMessageBox::warning( this, tr("SDI"), tr("Failed to save file.") );
   return false;
 }
 
 QTextStream stream( &file );
 stream << docWidget->toPlainText();
 
 currentFilename = filename;
 docWidget->document()->setModified( false );
 setWindowTitle( tr("%1[*] - %2" ).arg(filename).arg(tr("SDI")) );
 
 return true;

} void SdiWindow::loadFile( QString filename ) {

 QFile file( filename );
 if( !file.open( QIODevice::ReadOnly | QIODevice::Text ) )
 {
   QMessageBox::warning( this, tr("SDI"), tr("Failed to open file.") );
   return;
 }
 
 QTextStream stream( &file );
 docWidget->setPlainText( stream.readAll() );
 currentFilename = filename;
 docWidget->document()->setModified( false );  
 setWindowTitle( tr("%1[*] - %2" ).arg(filename).arg(tr("SDI")) );

}

Foundations of Qt Development\Chapter08\readwriteapplication\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 SdiWindow : public QMainWindow {

 Q_OBJECT
 

public:

 SdiWindow( QWidget *parent = 0 );
 

protected:

 void closeEvent( QCloseEvent *event );
 

private slots:

 void fileNew();
 void helpAbout();
 
 void fileOpen();
 bool fileSave();
 bool fileSaveAs();

private:

 void createActions();
 void createMenus();
 void createToolbars();
 bool isSafeToClose();
 bool saveFile( QString filename );
 void loadFile( QString filename );
 QString currentFilename;
 QTextEdit *docWidget;
 
 QAction *newAction;
 QAction *openAction;
 QAction *saveAction;
 QAction *saveAsAction;
 QAction *closeAction;
 QAction *exitAction;
 
 QAction *cutAction;
 QAction *copyAction;
 QAction *pasteAction;
 
 QAction *aboutAction;
 QAction *aboutQtAction;

};

  1. endif // SDIWINDOW_H


 </source>


Set up toolbar with QAction

<source lang="cpp">

Foundations of Qt Development\Chapter08\readwriteapplication\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();
 QObject::connect( &app, SIGNAL(lastWindowClosed()), &app, SLOT(quit()) );
 
 return app.exec();

}

Foundations of Qt Development\Chapter08\readwriteapplication\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 <QFile>
  9. include <QTextStream>
  10. include <QFileDialog>
  11. 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)) );
 
 createActions();
 createMenus();
 createToolbars();
 statusBar()->showMessage( tr("Done") );

}

void SdiWindow::closeEvent( QCloseEvent *event ) {

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

}

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()) );
 openAction = new QAction( tr("&Open"), this );
 openAction->setShortcut( tr("Ctrl+O") );
 openAction->setStatusTip( tr("Open a document") );
 connect( openAction, SIGNAL(triggered()), this, SLOT(fileOpen()) );

 saveAction = new QAction( tr("&Save"), this );
 saveAction->setShortcut( tr("Ctrl+S") );
 saveAction->setStatusTip( tr("Save the document") );
 connect( saveAction, SIGNAL(triggered()), this, SLOT(fileSave()) );

 saveAsAction = new QAction( tr("Save &As"), this );
 saveAsAction->setStatusTip( tr("Save the document as") );
 connect( saveAsAction, SIGNAL(triggered()), this, SLOT(fileSaveAs()) );

 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->addSeparator();
 menu->addAction( openAction );
 menu->addAction( saveAction );
 menu->addAction( saveAsAction );
 menu->addSeparator();
 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("&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 );

}

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::Save | QMessageBox::Discard | QMessageBox::Cancel ) )
   {
   case QMessageBox::Cancel:
     return false;
   case QMessageBox::Save:
     return fileSave();
   default:
     return true;
   }
 }
 return true;

} void SdiWindow::fileOpen() {

 QString filename = QFileDialog::getOpenFileName( this );
 if( filename.isEmpty() )
   return;
 if( currentFilename.isEmpty() && !docWidget->document()->isModified() )
   loadFile( filename );
 else
 {    
   SdiWindow *window = new SdiWindow();
   window->loadFile( filename );
   window->show();
 }

} bool SdiWindow::fileSave() {

 if( currentFilename.isEmpty() )
   return fileSaveAs();
 else
   return saveFile( currentFilename );  

} bool SdiWindow::fileSaveAs() {

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

} bool SdiWindow::saveFile( QString filename ) {

 QFile file( filename );
 if( !file.open( QIODevice::WriteOnly | QIODevice::Text ) )
 {
   QMessageBox::warning( this, tr("SDI"), tr("Failed to save file.") );
   return false;
 }
 
 QTextStream stream( &file );
 stream << docWidget->toPlainText();
 
 currentFilename = filename;
 docWidget->document()->setModified( false );
 setWindowTitle( tr("%1[*] - %2" ).arg(filename).arg(tr("SDI")) );
 
 return true;

} void SdiWindow::loadFile( QString filename ) {

 QFile file( filename );
 if( !file.open( QIODevice::ReadOnly | QIODevice::Text ) )
 {
   QMessageBox::warning( this, tr("SDI"), tr("Failed to open file.") );
   return;
 }
 
 QTextStream stream( &file );
 docWidget->setPlainText( stream.readAll() );
 currentFilename = filename;
 docWidget->document()->setModified( false );  
 setWindowTitle( tr("%1[*] - %2" ).arg(filename).arg(tr("SDI")) );

}

Foundations of Qt Development\Chapter08\readwriteapplication\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 SdiWindow : public QMainWindow {

 Q_OBJECT
 

public:

 SdiWindow( QWidget *parent = 0 );
 

protected:

 void closeEvent( QCloseEvent *event );
 

private slots:

 void fileNew();
 void helpAbout();
 
 void fileOpen();
 bool fileSave();
 bool fileSaveAs();

private:

 void createActions();
 void createMenus();
 void createToolbars();
 bool isSafeToClose();
 bool saveFile( QString filename );
 void loadFile( QString filename );
 QString currentFilename;
 QTextEdit *docWidget;
 
 QAction *newAction;
 QAction *openAction;
 QAction *saveAction;
 QAction *saveAsAction;
 QAction *closeAction;
 QAction *exitAction;
 
 QAction *cutAction;
 QAction *copyAction;
 QAction *pasteAction;
 
 QAction *aboutAction;
 QAction *aboutQtAction;

};

  1. endif // SDIWINDOW_H


 </source>