examples/widgets/scribble/scribblearea.cpp
changeset 0 1918ee327afb
child 3 41300fa6a67c
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/examples/widgets/scribble/scribblearea.cpp	Mon Jan 11 14:00:40 2010 +0000
@@ -0,0 +1,215 @@
+/****************************************************************************
+**
+** 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.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** No Commercial Usage
+** This file contains pre-release code and may not be distributed.
+** You may use this file in accordance with the terms and conditions
+** contained in the Technology Preview License Agreement accompanying
+** this package.
+**
+** 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.
+**
+** If you have questions regarding the use of this file, please contact
+** Nokia at qt-info@nokia.com.
+**
+**
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include <QtGui>
+
+#include "scribblearea.h"
+
+//! [0]
+ScribbleArea::ScribbleArea(QWidget *parent)
+    : QWidget(parent)
+{
+    setAttribute(Qt::WA_StaticContents);
+    modified = false;
+    scribbling = false;
+    myPenWidth = 1;
+    myPenColor = Qt::blue;
+}
+//! [0]
+
+//! [1]
+bool ScribbleArea::openImage(const QString &fileName)
+//! [1] //! [2]
+{
+    QImage loadedImage;
+    if (!loadedImage.load(fileName))
+        return false;
+
+    QSize newSize = loadedImage.size().expandedTo(size());
+    resizeImage(&loadedImage, newSize);
+    image = loadedImage;
+    modified = false;
+    update();
+    return true;
+}
+//! [2]
+
+//! [3]
+bool ScribbleArea::saveImage(const QString &fileName, const char *fileFormat)
+//! [3] //! [4]
+{
+    QImage visibleImage = image;
+    resizeImage(&visibleImage, size());
+
+    if (visibleImage.save(fileName, fileFormat)) {
+        modified = false;
+        return true;
+    } else {
+        return false;
+    }
+}
+//! [4]
+
+//! [5]
+void ScribbleArea::setPenColor(const QColor &newColor)
+//! [5] //! [6]
+{
+    myPenColor = newColor;
+}
+//! [6]
+
+//! [7]
+void ScribbleArea::setPenWidth(int newWidth)
+//! [7] //! [8]
+{
+    myPenWidth = newWidth;
+}
+//! [8]
+
+//! [9]
+void ScribbleArea::clearImage()
+//! [9] //! [10]
+{
+    image.fill(qRgb(255, 255, 255));
+    modified = true;
+    update();
+}
+//! [10]
+
+//! [11]
+void ScribbleArea::mousePressEvent(QMouseEvent *event)
+//! [11] //! [12]
+{
+    if (event->button() == Qt::LeftButton) {
+        lastPoint = event->pos();
+        scribbling = true;
+    }
+}
+
+void ScribbleArea::mouseMoveEvent(QMouseEvent *event)
+{
+    if ((event->buttons() & Qt::LeftButton) && scribbling)
+        drawLineTo(event->pos());
+}
+
+void ScribbleArea::mouseReleaseEvent(QMouseEvent *event)
+{
+    if (event->button() == Qt::LeftButton && scribbling) {
+        drawLineTo(event->pos());
+        scribbling = false;
+    }
+}
+
+//! [12] //! [13]
+void ScribbleArea::paintEvent(QPaintEvent * /* event */)
+//! [13] //! [14]
+{
+    QPainter painter(this);
+    painter.drawImage(QPoint(0, 0), image);
+}
+//! [14]
+
+//! [15]
+void ScribbleArea::resizeEvent(QResizeEvent *event)
+//! [15] //! [16]
+{
+    if (width() > image.width() || height() > image.height()) {
+        int newWidth = qMax(width() + 128, image.width());
+        int newHeight = qMax(height() + 128, image.height());
+        resizeImage(&image, QSize(newWidth, newHeight));
+        update();
+    }
+    QWidget::resizeEvent(event);
+}
+//! [16]
+
+//! [17]
+void ScribbleArea::drawLineTo(const QPoint &endPoint)
+//! [17] //! [18]
+{
+    QPainter painter(&image);
+    painter.setPen(QPen(myPenColor, myPenWidth, Qt::SolidLine, Qt::RoundCap,
+                        Qt::RoundJoin));
+    painter.drawLine(lastPoint, endPoint);
+    modified = true;
+
+    int rad = (myPenWidth / 2) + 2;
+    update(QRect(lastPoint, endPoint).normalized()
+                                     .adjusted(-rad, -rad, +rad, +rad));
+    lastPoint = endPoint;
+}
+//! [18]
+
+//! [19]
+void ScribbleArea::resizeImage(QImage *image, const QSize &newSize)
+//! [19] //! [20]
+{
+    if (image->size() == newSize)
+        return;
+
+    QImage newImage(newSize, QImage::Format_RGB32);
+    newImage.fill(qRgb(255, 255, 255));
+    QPainter painter(&newImage);
+    painter.drawImage(QPoint(0, 0), *image);
+    *image = newImage;
+}
+//! [20]
+
+//! [21]
+void ScribbleArea::print()
+{
+#ifndef QT_NO_PRINTER
+    QPrinter printer(QPrinter::HighResolution);
+ 
+    QPrintDialog *printDialog = new QPrintDialog(&printer, this);
+//! [21] //! [22]
+    if (printDialog->exec() == QDialog::Accepted) {
+        QPainter painter(&printer);
+        QRect rect = painter.viewport();
+        QSize size = image.size();
+        size.scale(rect.size(), Qt::KeepAspectRatio);
+        painter.setViewport(rect.x(), rect.y(), size.width(), size.height());
+        painter.setWindow(image.rect());
+        painter.drawImage(0, 0, image);
+    }
+#endif // QT_NO_PRINTER
+}
+//! [22]