1 /****************************************************************************

     2 **

     3 ** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).

     4 ** All rights reserved.

     5 ** Contact: Nokia Corporation (qt-info@nokia.com)

     6 **

     7 ** This file is part of the examples of the Qt Toolkit.

     8 **

     9 ** $QT_BEGIN_LICENSE:LGPL$

    10 ** No Commercial Usage

    11 ** This file contains pre-release code and may not be distributed.

    12 ** You may use this file in accordance with the terms and conditions

    13 ** contained in the Technology Preview License Agreement accompanying

    14 ** this package.

    15 **

    16 ** GNU Lesser General Public License Usage

    17 ** Alternatively, this file may be used under the terms of the GNU Lesser

    18 ** General Public License version 2.1 as published by the Free Software

    19 ** Foundation and appearing in the file LICENSE.LGPL included in the

    20 ** packaging of this file.  Please review the following information to

    21 ** ensure the GNU Lesser General Public License version 2.1 requirements

    22 ** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.

    23 **

    24 ** In addition, as a special exception, Nokia gives you certain additional

    25 ** rights.  These rights are described in the Nokia Qt LGPL Exception

    26 ** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.

    27 **

    28 ** If you have questions regarding the use of this file, please contact

    29 ** Nokia at qt-info@nokia.com.

    30 **

    31 **

    32 **

    33 **

    34 **

    35 **

    36 **

    37 **

    38 ** $QT_END_LICENSE$

    39 **

    40 ****************************************************************************/

    41 

    42 #include <QtGui>

    43 

    44 #include "scribblearea.h"

    45 

    46 //! [0]

    47 ScribbleArea::ScribbleArea(QWidget *parent)

    48     : QWidget(parent)

    49 {

    50     setAttribute(Qt::WA_StaticContents);

    51     modified = false;

    52     scribbling = false;

    53     myPenWidth = 1;

    54     myPenColor = Qt::blue;

    55 }

    56 //! [0]

    57 

    58 //! [1]

    59 bool ScribbleArea::openImage(const QString &fileName)

    60 //! [1] //! [2]

    61 {

    62     QImage loadedImage;

    63     if (!loadedImage.load(fileName))

    64         return false;

    65 

    66     QSize newSize = loadedImage.size().expandedTo(size());

    67     resizeImage(&loadedImage, newSize);

    68     image = loadedImage;

    69     modified = false;

    70     update();

    71     return true;

    72 }

    73 //! [2]

    74 

    75 //! [3]

    76 bool ScribbleArea::saveImage(const QString &fileName, const char *fileFormat)

    77 //! [3] //! [4]

    78 {

    79     QImage visibleImage = image;

    80     resizeImage(&visibleImage, size());

    81 

    82     if (visibleImage.save(fileName, fileFormat)) {

    83         modified = false;

    84         return true;

    85     } else {

    86         return false;

    87     }

    88 }

    89 //! [4]

    90 

    91 //! [5]

    92 void ScribbleArea::setPenColor(const QColor &newColor)

    93 //! [5] //! [6]

    94 {

    95     myPenColor = newColor;

    96 }

    97 //! [6]

    98 

    99 //! [7]

   100 void ScribbleArea::setPenWidth(int newWidth)

   101 //! [7] //! [8]

   102 {

   103     myPenWidth = newWidth;

   104 }

   105 //! [8]

   106 

   107 //! [9]

   108 void ScribbleArea::clearImage()

   109 //! [9] //! [10]

   110 {

   111     image.fill(qRgb(255, 255, 255));

   112     modified = true;

   113     update();

   114 }

   115 //! [10]

   116 

   117 //! [11]

   118 void ScribbleArea::mousePressEvent(QMouseEvent *event)

   119 //! [11] //! [12]

   120 {

   121     if (event->button() == Qt::LeftButton) {

   122         lastPoint = event->pos();

   123         scribbling = true;

   124     }

   125 }

   126 

   127 void ScribbleArea::mouseMoveEvent(QMouseEvent *event)

   128 {

   129     if ((event->buttons() & Qt::LeftButton) && scribbling)

   130         drawLineTo(event->pos());

   131 }

   132 

   133 void ScribbleArea::mouseReleaseEvent(QMouseEvent *event)

   134 {

   135     if (event->button() == Qt::LeftButton && scribbling) {

   136         drawLineTo(event->pos());

   137         scribbling = false;

   138     }

   139 }

   140 

   141 //! [12] //! [13]

   142 void ScribbleArea::paintEvent(QPaintEvent * /* event */)

   143 //! [13] //! [14]

   144 {

   145     QPainter painter(this);

   146     painter.drawImage(QPoint(0, 0), image);

   147 }

   148 //! [14]

   149 

   150 //! [15]

   151 void ScribbleArea::resizeEvent(QResizeEvent *event)

   152 //! [15] //! [16]

   153 {

   154     if (width() > image.width() || height() > image.height()) {

   155         int newWidth = qMax(width() + 128, image.width());

   156         int newHeight = qMax(height() + 128, image.height());

   157         resizeImage(&image, QSize(newWidth, newHeight));

   158         update();

   159     }

   160     QWidget::resizeEvent(event);

   161 }

   162 //! [16]

   163 

   164 //! [17]

   165 void ScribbleArea::drawLineTo(const QPoint &endPoint)

   166 //! [17] //! [18]

   167 {

   168     QPainter painter(&image);

   169     painter.setPen(QPen(myPenColor, myPenWidth, Qt::SolidLine, Qt::RoundCap,

   170                         Qt::RoundJoin));

   171     painter.drawLine(lastPoint, endPoint);

   172     modified = true;

   173 

   174     int rad = (myPenWidth / 2) + 2;

   175     update(QRect(lastPoint, endPoint).normalized()

   176                                      .adjusted(-rad, -rad, +rad, +rad));

   177     lastPoint = endPoint;

   178 }

   179 //! [18]

   180 

   181 //! [19]

   182 void ScribbleArea::resizeImage(QImage *image, const QSize &newSize)

   183 //! [19] //! [20]

   184 {

   185     if (image->size() == newSize)

   186         return;

   187 

   188     QImage newImage(newSize, QImage::Format_RGB32);

   189     newImage.fill(qRgb(255, 255, 255));

   190     QPainter painter(&newImage);

   191     painter.drawImage(QPoint(0, 0), *image);

   192     *image = newImage;

   193 }

   194 //! [20]

   195 

   196 //! [21]

   197 void ScribbleArea::print()

   198 {

   199 #ifndef QT_NO_PRINTER

   200     QPrinter printer(QPrinter::HighResolution);

   201  

   202     QPrintDialog *printDialog = new QPrintDialog(&printer, this);

   203 //! [21] //! [22]

   204     if (printDialog->exec() == QDialog::Accepted) {

   205         QPainter painter(&printer);

   206         QRect rect = painter.viewport();

   207         QSize size = image.size();

   208         size.scale(rect.size(), Qt::KeepAspectRatio);

   209         painter.setViewport(rect.x(), rect.y(), size.width(), size.height());

   210         painter.setWindow(image.rect());

   211         painter.drawImage(0, 0, image);

   212     }

   213 #endif // QT_NO_PRINTER

   214 }

   215 //! [22]