document.h Example File

  /****************************************************************************
  **
  ** Copyright (C) 2016 The Qt Company Ltd.
  ** Contact: https://www.qt.io/licensing/
  **
  ** This file is part of the demonstration applications of the Qt Toolkit.
  **
  ** $QT_BEGIN_LICENSE:BSD$
  ** 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 The Qt Company. For licensing terms
  ** and conditions see https://www.qt.io/terms-conditions. For further
  ** information use the contact form at https://www.qt.io/contact-us.
  **
  ** BSD License Usage
  ** Alternatively, 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 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 };

      explicit 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) override;
      void mousePressEvent(QMouseEvent *event) override;
      void mouseReleaseEvent(QMouseEvent *event) override;
      void mouseMoveEvent(QMouseEvent *event) override;

  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