paintarea.h Example File

 /****************************************************************************
 **
 ** Copyright (C) 2015 The Qt Company Ltd.
 ** Contact: http://www.qt.io/licensing/
 **
 ** 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 The Qt Company Ltd 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."
 **
 ** $QT_END_LICENSE$
 **
 ****************************************************************************/

 #ifndef PAINTAREA_H
 #define PAINTAREA_H

 #include <QColor>
 #include <QImage>
 #include <QPainterPath>
 #include <QWidget>

 class BrushInterface;

 class PaintArea : public QWidget
 {
     Q_OBJECT

 public:
     PaintArea(QWidget *parent = 0);

     bool openImage(const QString &fileName);
     bool saveImage(const QString &fileName, const char *fileFormat);
     void setImage(const QImage &image);
     void insertShape(const QPainterPath &path);
     void setBrushColor(const QColor &color);
     void setBrushWidth(int width);
     void setBrush(BrushInterface *brushInterface, const QString &brush);

     QImage image() const { return theImage; }
     QColor brushColor() const { return color; }
     int brushWidth() const { return thickness; }
     QSize sizeHint() const;

 protected:
     void paintEvent(QPaintEvent *event);
     void mousePressEvent(QMouseEvent *event);
     void mouseMoveEvent(QMouseEvent *event);
     void mouseReleaseEvent(QMouseEvent *event);

 private:
     void setupPainter(QPainter &painter);

     QImage theImage;
     QColor color;
     int thickness;

     BrushInterface *brushInterface;
     QString brush;
     QPoint lastPos;

     QPainterPath pendingPath;
 };

 #endif