document.h Example File

 /****************************************************************************
 **
 ** Copyright (C) 2013 Digia Plc and/or its subsidiary(-ies).
 ** Contact: http://www.qt-project.org/legal
 **
 ** This file is part of the demonstration applications of the Qt Toolkit.
 **
 ** $QT_BEGIN_LICENSE:LGPL$
 ** Commercial License Usage
 ** Licensees holding valid commercial Qt licenses may use this file in
 ** accordance with the commercial license agreement provided with the
 ** Software or, alternatively, in accordance with the terms contained in
 ** a written agreement between you and Digia.  For licensing terms and
 ** conditions see http://qt.digia.com/licensing.  For further information
 ** use the contact form at http://qt.digia.com/contact-us.
 **
 ** 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, Digia gives you certain additional
 ** rights.  These rights are described in the Digia Qt LGPL Exception
 ** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
 **
 ** GNU General Public License Usage
 ** Alternatively, this file may be used under the terms of the GNU
 ** General Public License version 3.0 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 the GNU General Public License version 3.0 requirements will be
 ** met: http://www.gnu.org/copyleft/gpl.html.
 **
 **
 ** $QT_END_LICENSE$
 **
 ****************************************************************************/

 #ifndef DOCUMENT_H
 #define DOCUMENT_H

 #include <QWidget>

 QT_FORWARD_DECLARE_CLASS(QUndoStack)
 QT_FORWARD_DECLARE_CLASS(QTextStream)

 class Shape
 {
 public:
     enum Type { Rectangle, Circle, Triangle };

     Shape(Type type = Rectangle, const QColor &color = Qt::red, const QRect &rect = QRect());

     Type type() const;
     QString name() const;
     QRect rect() const;
     QRect resizeHandle() const;
     QColor color() const;

     static QString typeToString(Type type);
     static Type stringToType(const QString &s, bool *ok = 0);

     static const QSize minSize;

 private:
     Type m_type;
     QRect m_rect;
     QColor m_color;
     QString m_name;

     friend class Document;
 };

 class Document : public QWidget
 {
     Q_OBJECT

 public:
     Document(QWidget *parent = 0);

     QString addShape(const Shape &shape);
     void deleteShape(const QString &shapeName);
     Shape shape(const QString &shapeName) const;
     QString currentShapeName() const;

     void setShapeRect(const QString &shapeName, const QRect &rect);
     void setShapeColor(const QString &shapeName, const QColor &color);

     bool load(QTextStream &stream);
     void save(QTextStream &stream);

     QString fileName() const;
     void setFileName(const QString &fileName);

     QUndoStack *undoStack() const;

 signals:
     void currentShapeChanged(const QString &shapeName);

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

 private:
     void setCurrentShape(int index);
     int indexOf(const QString &shapeName) const;
     int indexAt(const QPoint &pos) const;
     QString uniqueName(const QString &name) const;

     QList<Shape> m_shapeList;
     int m_currentIndex;
     int m_mousePressIndex;
     QPoint m_mousePressOffset;
     bool m_resizeHandlePressed;
     QString m_fileName;

     QUndoStack *m_undoStack;
 };

 #endif // DOCUMENT_H