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     3 ** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).

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    16 ** GNU Lesser General Public License Usage

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    38 ** $QT_END_LICENSE$

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    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     QRect dirtyRect = event->rect();

   147     painter.drawImage(dirtyRect, image, dirtyRect);

   148 }

   149 //! [14]

   150 

   151 //! [15]

   152 void ScribbleArea::resizeEvent(QResizeEvent *event)

   153 //! [15] //! [16]

   154 {

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

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

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

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

   159         update();

   160     }

   161     QWidget::resizeEvent(event);

   162 }

   163 //! [16]

   164 

   165 //! [17]

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

   167 //! [17] //! [18]

   168 {

   169     QPainter painter(&image);

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

   171                         Qt::RoundJoin));

   172     painter.drawLine(lastPoint, endPoint);

   173     modified = true;

   174 

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

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

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

   178     lastPoint = endPoint;

   179 }

   180 //! [18]

   181 

   182 //! [19]

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

   184 //! [19] //! [20]

   185 {

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

   187         return;

   188 

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

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

   191     QPainter painter(&newImage);

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

   193     *image = newImage;

   194 }

   195 //! [20]

   196 

   197 //! [21]

   198 void ScribbleArea::print()

   199 {

   200 #ifndef QT_NO_PRINTER

   201     QPrinter printer(QPrinter::HighResolution);

   202  

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

   204 //! [21] //! [22]

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

   206         QPainter painter(&printer);

   207         QRect rect = painter.viewport();

   208         QSize size = image.size();

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

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

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

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

   213     }

   214 #endif // QT_NO_PRINTER

   215 }

   216 //! [22]