Qt:Документация 4.3.2/tools-plugandpaint-paintarea-cpp

Материал из Wiki.crossplatform.ru

Перейти к: навигация, поиск
40px Внимание: Актуальная версия перевода документации находится здесь

__NOTOC__

Image:qt-logo.png

Главная · Все классы · Основные классы · Классы по группам · Модули · Функции

Image:trolltech-logo.png

[править] paintarea.cpp Example File
tools/plugandpaint/paintarea.cpp

 /****************************************************************************
 **
 ** Copyright (C) 2005-2007 Trolltech ASA. All rights reserved.
 **
 ** This file is part of the example classes of the Qt Toolkit.
 **
 ** This file may be used under the terms of the GNU General Public
 ** License version 2.0 as published by the Free Software Foundation
 ** and appearing in the file LICENSE.GPL included in the packaging of
 ** this file.  Please review the following information to ensure GNU
 ** General Public Licensing requirements will be met:
 ** http://trolltech.com/products/qt/licenses/licensing/opensource/
 **
 ** If you are unsure which license is appropriate for your use, please
 ** review the following information:
 ** http://trolltech.com/products/qt/licenses/licensing/licensingoverview
 ** or contact the sales department at sales@trolltech.com.
 **
 ** In addition, as a special exception, Trolltech gives you certain
 ** additional rights. These rights are described in the Trolltech GPL
 ** Exception version 1.0, which can be found at
 ** http://www.trolltech.com/products/qt/gplexception/ and in the file
 ** GPL_EXCEPTION.txt in this package.
 **
 ** In addition, as a special exception, Trolltech, as the sole copyright
 ** holder for Qt Designer, grants users of the Qt/Eclipse Integration
 ** plug-in the right for the Qt/Eclipse Integration to link to
 ** functionality provided by Qt Designer and its related libraries.
 **
 ** Trolltech reserves all rights not expressly granted herein.
 **
 ** Trolltech ASA (c) 2007
 **
 ** This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
 ** WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 **
 ****************************************************************************/
 
 #include "interfaces.h"
 #include "paintarea.h"
 
 #include <QPainter>
 #include <QMouseEvent>
 
 PaintArea::PaintArea(QWidget *parent) :
     QWidget(parent),
     theImage(500, 400, QImage::Format_RGB32),
     color(Qt::blue),
     thickness(3),
     brushInterface(0),
     lastPos(-1, -1)
 {
     setAttribute(Qt::WA_StaticContents);
     setAttribute(Qt::WA_NoBackground);
 
     theImage.fill(qRgb(255, 255, 255));
 }
 
 bool PaintArea::openImage(const QString &amp;fileName)
 {
     QImage image;
     if (!image.load(fileName))
         return false;
 
     setImage(image);
     return true;
 }
 
 bool PaintArea::saveImage(const QString &amp;fileName, const char *fileFormat)
 {
     return theImage.save(fileName, fileFormat);
 }
 
 void PaintArea::setImage(const QImage &amp;image)
 {
     theImage = image.convertToFormat(QImage::Format_RGB32);
     update();
     updateGeometry();
 }
 
 void PaintArea::insertShape(const QPainterPath &amp;path)
 {
     pendingPath = path;
     setCursor(Qt::CrossCursor);
 }
 
 void PaintArea::setBrushColor(const QColor &amp;color)
 {
     this->color = color;
 }
 
 void PaintArea::setBrushWidth(int width)
 {
     thickness = width;
 }
 
 void PaintArea::setBrush(BrushInterface *brushInterface, const QString &amp;brush)
 {
     this->brushInterface = brushInterface;
     this->brush = brush;
 }
 
 QSize PaintArea::sizeHint() const
 {
     return theImage.size();
 }
 
 void PaintArea::paintEvent(QPaintEvent * /* event */)
 {
     QPainter painter(this);
     painter.drawImage(QPoint(0, 0), theImage);
 }
 
 void PaintArea::mousePressEvent(QMouseEvent *event)
 {
     if (event->button() == Qt::LeftButton) {
         if (!pendingPath.isEmpty()) {
             QPainter painter(&amp;theImage);
             setupPainter(painter);
 
             const QRectF boundingRect = pendingPath.boundingRect();
             QLinearGradient gradient(boundingRect.topRight(),
                                      boundingRect.bottomLeft());
             gradient.setColorAt(0.0, QColor(color.red(), color.green(),
                                             color.blue(), 63));
             gradient.setColorAt(1.0, QColor(color.red(), color.green(),
                                             color.blue(), 191));
             painter.setBrush(gradient);
             painter.translate(event->pos() - boundingRect.center());
             painter.drawPath(pendingPath);
 
             pendingPath = QPainterPath();
             unsetCursor();
             update();
         } else {
             if (brushInterface) {
                 QPainter painter(&amp;theImage);
                 setupPainter(painter);
                 const QRect rect = brushInterface->mousePress(brush, painter,
                                                               event->pos());
                 update(rect);
             }
 
             lastPos = event->pos();
         }
     }
 }
 
 void PaintArea::mouseMoveEvent(QMouseEvent *event)
 {
     if ((event->buttons() &amp; Qt::LeftButton) &amp;&amp; lastPos != QPoint(-1, -1)) {
         if (brushInterface) {
             QPainter painter(&amp;theImage);
             setupPainter(painter);
             const QRect rect = brushInterface->mouseMove(brush, painter, lastPos,
                                                          event->pos());
             update(rect);
         }
 
         lastPos = event->pos();
     }
 }
 
 void PaintArea::mouseReleaseEvent(QMouseEvent *event)
 {
     if (event->button() == Qt::LeftButton &amp;&amp; lastPos != QPoint(-1, -1)) {
         if (brushInterface) {
             QPainter painter(&amp;theImage);
             setupPainter(painter);
             QRect rect = brushInterface->mouseRelease(brush, painter,
                                                       event->pos());
             update(rect);
         }
 
         lastPos = QPoint(-1, -1);
     }
 }
 
 void PaintArea::setupPainter(QPainter &amp;painter)
 {
     painter.setRenderHint(QPainter::Antialiasing, true);
     painter.setPen(QPen(color, thickness, Qt::SolidLine, Qt::RoundCap,
                    Qt::RoundJoin));
 }

Copyright © 2007 Trolltech Trademarks
Qt 4.3.2