Qt Reference Documentation

- Qt 4.8
- ALL VERSIONS

- A
- A
- A
- Print

# mainwindow.cpp Example File

widgets/tablet/mainwindow.cpp

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

     #include <QtGui>

     #include "mainwindow.h"
     #include "tabletcanvas.h"

     MainWindow::MainWindow(TabletCanvas *canvas)
     {
         myCanvas = canvas;
         createActions();
         createMenus();

         myCanvas->setColor(Qt::red);
         myCanvas->setLineWidthType(TabletCanvas::LineWidthPressure);
         myCanvas->setAlphaChannelType(TabletCanvas::NoAlpha);
         myCanvas->setColorSaturationType(TabletCanvas::NoSaturation);

         setWindowTitle(tr("Tablet Example"));
         setCentralWidget(myCanvas);
     }

     void MainWindow::brushColorAct()
     {
         QColor color = QColorDialog::getColor(myCanvas->color());

         if (color.isValid())
             myCanvas->setColor(color);
     }

     void MainWindow::alphaActionTriggered(QAction *action)
     {
         if (action == alphaChannelPressureAction) {
             myCanvas->setAlphaChannelType(TabletCanvas::AlphaPressure);
         } else if (action == alphaChannelTiltAction) {
             myCanvas->setAlphaChannelType(TabletCanvas::AlphaTilt);
         } else {
             myCanvas->setAlphaChannelType(TabletCanvas::NoAlpha);
         }
     }

     void MainWindow::lineWidthActionTriggered(QAction *action)
     {
         if (action == lineWidthPressureAction) {
             myCanvas->setLineWidthType(TabletCanvas::LineWidthPressure);
         } else if (action == lineWidthTiltAction) {
             myCanvas->setLineWidthType(TabletCanvas::LineWidthTilt);
         } else {
             myCanvas->setLineWidthType(TabletCanvas::NoLineWidth);
         }
     }

     void MainWindow::saturationActionTriggered(QAction *action)
     {
         if (action == colorSaturationVTiltAction) {
             myCanvas->setColorSaturationType(TabletCanvas::SaturationVTilt);
         } else if (action == colorSaturationHTiltAction) {
             myCanvas->setColorSaturationType(TabletCanvas::SaturationHTilt);
         } else if (action == colorSaturationPressureAction) {
             myCanvas->setColorSaturationType(TabletCanvas::SaturationPressure);
         } else {
             myCanvas->setColorSaturationType(TabletCanvas::NoSaturation);
         }
     }

     void MainWindow::saveAct()
     {
         QString path = QDir::currentPath() + "/untitled.png";
         QString fileName = QFileDialog::getSaveFileName(this, tr("Save Picture"),
                                  path);

         if (!myCanvas->saveImage(fileName))
             QMessageBox::information(this, "Error Saving Picture",
                                      "Could not save the image");
     }

     void MainWindow::loadAct()
     {
         QString fileName = QFileDialog::getOpenFileName(this, tr("Open Picture"),
                                                         QDir::currentPath());

         if (!myCanvas->loadImage(fileName))
             QMessageBox::information(this, "Error Opening Picture",
                                      "Could not open picture");
     }

     void MainWindow::aboutAct()
     {
         QMessageBox::about(this, tr("About Tablet Example"),
                            tr("This example shows use of a Wacom tablet in Qt"));
     }

     void MainWindow::createActions()
     {
         brushColorAction = new QAction(tr("&Brush Color..."), this);
         brushColorAction->setShortcut(tr("Ctrl+C"));
         connect(brushColorAction, SIGNAL(triggered()),
                 this, SLOT(brushColorAct()));

         alphaChannelPressureAction = new QAction(tr("&Pressure"), this);
         alphaChannelPressureAction->setCheckable(true);

         alphaChannelTiltAction = new QAction(tr("&Tilt"), this);
         alphaChannelTiltAction->setCheckable(true);

         noAlphaChannelAction = new QAction(tr("No Alpha Channel"), this);
         noAlphaChannelAction->setCheckable(true);
         noAlphaChannelAction->setChecked(true);

         alphaChannelGroup = new QActionGroup(this);
         alphaChannelGroup->addAction(alphaChannelPressureAction);
         alphaChannelGroup->addAction(alphaChannelTiltAction);
         alphaChannelGroup->addAction(noAlphaChannelAction);
         connect(alphaChannelGroup, SIGNAL(triggered(QAction*)),
                 this, SLOT(alphaActionTriggered(QAction*)));

         colorSaturationVTiltAction = new QAction(tr("&Vertical Tilt"), this);
         colorSaturationVTiltAction->setCheckable(true);

         colorSaturationHTiltAction = new QAction(tr("&Horizontal Tilt"), this);
         colorSaturationHTiltAction->setCheckable(true);

         colorSaturationPressureAction = new QAction(tr("&Pressure"), this);
         colorSaturationPressureAction->setCheckable(true);

         noColorSaturationAction = new QAction(tr("&No Color Saturation"), this);
         noColorSaturationAction->setCheckable(true);
         noColorSaturationAction->setChecked(true);

         colorSaturationGroup = new QActionGroup(this);
         colorSaturationGroup->addAction(colorSaturationVTiltAction);
         colorSaturationGroup->addAction(colorSaturationHTiltAction);
         colorSaturationGroup->addAction(colorSaturationPressureAction);
         colorSaturationGroup->addAction(noColorSaturationAction);
         connect(colorSaturationGroup, SIGNAL(triggered(QAction*)),
                 this, SLOT(saturationActionTriggered(QAction*)));

         lineWidthPressureAction = new QAction(tr("&Pressure"), this);
         lineWidthPressureAction->setCheckable(true);
         lineWidthPressureAction->setChecked(true);

         lineWidthTiltAction = new QAction(tr("&Tilt"), this);
         lineWidthTiltAction->setCheckable(true);

         lineWidthFixedAction = new QAction(tr("&Fixed"), this);
         lineWidthFixedAction->setCheckable(true);

         lineWidthGroup = new QActionGroup(this);
         lineWidthGroup->addAction(lineWidthPressureAction);
         lineWidthGroup->addAction(lineWidthTiltAction);
         lineWidthGroup->addAction(lineWidthFixedAction);
         connect(lineWidthGroup, SIGNAL(triggered(QAction*)),
                 this, SLOT(lineWidthActionTriggered(QAction*)));

         exitAction = new QAction(tr("E&xit"), this);
         exitAction->setShortcuts(QKeySequence::Quit);
         connect(exitAction, SIGNAL(triggered()),
                 this, SLOT(close()));

         loadAction = new QAction(tr("&Open..."), this);
         loadAction->setShortcuts(QKeySequence::Open);
         connect(loadAction, SIGNAL(triggered()),
                 this, SLOT(loadAct()));

         saveAction = new QAction(tr("&Save As..."), this);
         saveAction->setShortcuts(QKeySequence::SaveAs);
         connect(saveAction, SIGNAL(triggered()),
                 this, SLOT(saveAct()));

         aboutAction = new QAction(tr("A&bout"), this);
         aboutAction->setShortcut(tr("Ctrl+B"));
         connect(aboutAction, SIGNAL(triggered()),
                 this, SLOT(aboutAct()));

         aboutQtAction = new QAction(tr("About &Qt"), this);
         aboutQtAction->setShortcut(tr("Ctrl+Q"));
         connect(aboutQtAction, SIGNAL(triggered()),
                 qApp, SLOT(aboutQt()));
     }

     void MainWindow::createMenus()
     {
         fileMenu = menuBar()->addMenu(tr("&File"));
         fileMenu->addAction(loadAction);
         fileMenu->addAction(saveAction);
         fileMenu->addSeparator();
         fileMenu->addAction(exitAction);

         brushMenu = menuBar()->addMenu(tr("&Brush"));
         brushMenu->addAction(brushColorAction);

         tabletMenu = menuBar()->addMenu(tr("&Tablet"));

         lineWidthMenu = tabletMenu->addMenu(tr("&Line Width"));
         lineWidthMenu->addAction(lineWidthPressureAction);
         lineWidthMenu->addAction(lineWidthTiltAction);
         lineWidthMenu->addAction(lineWidthFixedAction);

         alphaChannelMenu = tabletMenu->addMenu(tr("&Alpha Channel"));
         alphaChannelMenu->addAction(alphaChannelPressureAction);
         alphaChannelMenu->addAction(alphaChannelTiltAction);
         alphaChannelMenu->addAction(noAlphaChannelAction);

         colorSaturationMenu = tabletMenu->addMenu(tr("&Color Saturation"));
         colorSaturationMenu->addAction(colorSaturationVTiltAction);
         colorSaturationMenu->addAction(colorSaturationHTiltAction);
         colorSaturationMenu->addAction(noColorSaturationAction);

         helpMenu = menuBar()->addMenu("&Help");
         helpMenu->addAction(aboutAction);
         helpMenu->addAction(aboutQtAction);
     }