examples/touch/fingerpaint/scribblearea.cpp
changeset 37 758a864f9613
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/examples/touch/fingerpaint/scribblearea.cpp	Mon Oct 04 01:19:32 2010 +0300
@@ -0,0 +1,211 @@
+/****************************************************************************
+**
+** Copyright (C) 2010 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.
+**
+** $QT_BEGIN_LICENSE:BSD$
+** 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 Nokia Corporation and its Subsidiary(-ies) 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 "scribblearea.h"
+
+//! [0]
+ScribbleArea::ScribbleArea(QWidget *parent)
+    : QWidget(parent)
+{
+    setAttribute(Qt::WA_AcceptTouchEvents);
+    setAttribute(Qt::WA_StaticContents);
+    modified = false;
+
+    myPenColors
+            << QColor("green")
+            << QColor("purple")
+            << QColor("red")
+            << QColor("blue")
+            << QColor("yellow")
+
+            << QColor("pink")
+            << QColor("orange")
+            << QColor("brown")
+            << QColor("grey")
+            << QColor("black");
+}
+//! [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]
+
+//! [9]
+void ScribbleArea::clearImage()
+//! [9] //! [10]
+{
+    image.fill(qRgb(255, 255, 255));
+    modified = true;
+    update();
+}
+//! [10]
+
+//! [12] //! [13]
+void ScribbleArea::paintEvent(QPaintEvent *event)
+//! [13] //! [14]
+{
+    QPainter painter(this);
+    const QRect rect = event->rect();
+    painter.drawImage(rect.topLeft(), image, rect);
+}
+//! [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]
+
+//! [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]
+
+bool ScribbleArea::event(QEvent *event)
+{
+    switch (event->type()) {
+    case QEvent::TouchBegin:
+    case QEvent::TouchUpdate:
+    case QEvent::TouchEnd:
+    {
+        QList<QTouchEvent::TouchPoint> touchPoints = static_cast<QTouchEvent *>(event)->touchPoints();
+        foreach (const QTouchEvent::TouchPoint &touchPoint, touchPoints) {
+            switch (touchPoint.state()) {
+            case Qt::TouchPointStationary:
+                // don't do anything if this touch point hasn't moved
+                continue;
+            default:
+                {
+                    QRectF rect = touchPoint.rect();
+                    if (rect.isEmpty()) {
+                        qreal diameter = qreal(50) * touchPoint.pressure();
+                        rect.setSize(QSizeF(diameter, diameter));
+                    }
+
+                    QPainter painter(&image);
+                    painter.setPen(Qt::NoPen);
+                    painter.setBrush(myPenColors.at(touchPoint.id() % myPenColors.count()));
+                    painter.drawEllipse(rect);
+                    painter.end();
+
+                    modified = true;
+                    int rad = 2;
+                    update(rect.toRect().adjusted(-rad,-rad, +rad, +rad));
+                }
+                break;
+            }
+        }
+        break;
+    }
+    default:
+        return QWidget::event(event);
+    }
+    return true;
+}