qgslayertreenode.h

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/***************************************************************************
  qgslayertreenode.h
  --------------------------------------
  Date                 : May 2014
  Copyright            : (C) 2014 by Martin Dobias
  Email                : wonder dot sk at gmail dot com
 ***************************************************************************
 *                                                                         *
 *   This program is free software; you can redistribute it and/or modify  *
 *   it under the terms of the GNU General Public License as published by  *
 *   the Free Software Foundation; either version 2 of the License, or     *
 *   (at your option) any later version.                                   *
 *                                                                         *
 ***************************************************************************/

#ifndef QGSLAYERTREENODE_H
#define QGSLAYERTREENODE_H

#include <QObject>

#include "qgsobjectcustomproperties.h"

class QDomElement;

class CORE_EXPORT QgsLayerTreeNode : public QObject
{
    Q_OBJECT
  public:

    enum NodeType
    {
      NodeGroup,   
      NodeLayer    
    };

    ~QgsLayerTreeNode();

    NodeType nodeType() { return mNodeType; }
    QgsLayerTreeNode* parent() { return mParent; }
    QList<QgsLayerTreeNode*> children() { return mChildren; }

    static QgsLayerTreeNode* readXML( QDomElement& element );
    virtual void writeXML( QDomElement& parentElement ) = 0;

    virtual QString dump() const = 0;

    virtual QgsLayerTreeNode* clone() const = 0;

    bool isExpanded() const;
    void setExpanded( bool expanded );

    void setCustomProperty( const QString& key, const QVariant& value );
    QVariant customProperty( const QString& key, const QVariant& defaultValue = QVariant() ) const;
    void removeCustomProperty( const QString& key );
    QStringList customProperties() const;

  signals:

    void willAddChildren( QgsLayerTreeNode* node, int indexFrom, int indexTo );
    void addedChildren( QgsLayerTreeNode* node, int indexFrom, int indexTo );
    void willRemoveChildren( QgsLayerTreeNode* node, int indexFrom, int indexTo );
    void removedChildren( QgsLayerTreeNode* node, int indexFrom, int indexTo );
    void visibilityChanged( QgsLayerTreeNode* node, Qt::CheckState state );
    void customPropertyChanged( QgsLayerTreeNode* node, QString key );
    void expandedChanged( QgsLayerTreeNode* node, bool expanded );

  protected:

    QgsLayerTreeNode( NodeType t );
    QgsLayerTreeNode( const QgsLayerTreeNode& other );

    // low-level utility functions

    void readCommonXML( QDomElement& element );
    void writeCommonXML( QDomElement& element );

    void insertChildrenPrivate( int index, QList<QgsLayerTreeNode*> nodes );
    void removeChildrenPrivate( int from, int count );


  protected:
    NodeType mNodeType;
    QgsLayerTreeNode* mParent;
    QList<QgsLayerTreeNode*> mChildren;
    bool mExpanded;
    QgsObjectCustomProperties mProperties;
};




#endif // QGSLAYERTREENODE_H