qgslegendlayerfilegroup.cpp

一个非常好的GIS开源新版本

/***************************************************************************
                         qgslegendlayerfilegroup.cpp  -  description
                             -------------------
    begin                : Juli 2005
    copyright            : (C) 2005 by Marco Hugentobler
    email                : [e-mail]
 ***************************************************************************/

/***************************************************************************
 *                                                                         *
 *   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.                                   *
 *                                                                         *
 ***************************************************************************/

#include "qgslegendlayer.h"
#include "qgslegendlayerfilegroup.h"
#include "qgslegendlayerfile.h"
#include "qgslegendsymbologygroup.h"
#include "qgsmaplayer.h"

QgsLegendLayerFileGroup::QgsLegendLayerFileGroup(QTreeWidgetItem* theItem, QString theString): QgsLegendItem(theItem, theString)
{
    mType = LEGEND_LAYER_FILE_GROUP;
    setText(0, theString);
}

QgsLegendItem::DRAG_ACTION QgsLegendLayerFileGroup::accept(LEGEND_ITEM_TYPE type)
{
    if ( type == LEGEND_LAYER_FILE )
      {
	return INSERT; //there should be a way to already test, if the layers are symbology compatible
      }
    else
      {
	return NO_ACTION;
      }
}

QgsLegendItem::DRAG_ACTION QgsLegendLayerFileGroup::accept(const QgsLegendItem* li) const
{
#ifdef QGISDEBUG
  qWarning("in QgsLegendLayerFileGroup::accept");
#endif
  if(li)
    {
      LEGEND_ITEM_TYPE type = li->type();
      if ( type == LEGEND_LAYER_FILE /*&& this != li->parent()*/)
      {
	if(child(0) == 0)
	  {
	    return INSERT;
	  }
	else
	  {
	    QgsLegendLayerFile* llf = dynamic_cast<QgsLegendLayerFile*>(child(0));
	    if(llf)
	      {
		QgsMapLayer* childlayer = llf->layer();
		const QgsMapLayer* newlayer = (dynamic_cast<const QgsLegendLayerFile*>(li))->layer();
		if(newlayer->isSymbologyCompatible(*childlayer))
		  {
		    return INSERT;
		  }
	      }
	  }
      }
    }
  return NO_ACTION;
}

bool QgsLegendLayerFileGroup::insert(QgsLegendItem* newItem)
{
  if ( newItem->type() == LEGEND_LAYER_FILE )
    {
      QgsLegendItem* oldItem = firstChild();

      if(!oldItem)//this item is the first child
	{
	  insertChild(0, newItem);
	  return true;
	}
      //there are already legend layer files
      
      //find the lowest sibling
      while(oldItem->nextSibling() != 0)
	{
	  oldItem = oldItem->nextSibling();
	}
      QgsLegendLayerFile* thefile = dynamic_cast<QgsLegendLayerFile*>(oldItem);
      
      if(!thefile)
	{
	  return false;
	}
      QgsMapLayer* thelayer = thefile->layer();
      if(!thelayer)
	{
	  return false;
	}
      QgsMapLayer* newLayer = (dynamic_cast<QgsLegendLayerFile*>(newItem))->layer();
      if(newLayer->isSymbologyCompatible(*thelayer))
	{	
	  insertChild(childCount(), newItem);
	  return true;
	}
      else
	{
	  return false;
	}  
    }
  else
    {
      return false;
    }
}

bool QgsLegendLayerFileGroup::containsLegendLayerFile(const QgsLegendLayerFile* llf) const
{
  bool result = false;
  for(int i = 0; i < childCount(); ++i)
    {
      if(llf == child(i))
	{
	  result = true;
	  break;
	}
    }
  return result;
}

void QgsLegendLayerFileGroup::receive(QgsLegendItem* newChild)
{
  if(newChild->type() == LEGEND_LAYER_FILE)
    {
      QgsLegendLayer* ll = dynamic_cast<QgsLegendLayer*>(parent());
      if(ll)
	{
	  ll->updateIcon();
	  ll->updateCheckState();
	}
    }
}

void QgsLegendLayerFileGroup::release(QgsLegendItem* formerChild)
{
#ifdef QGISDEBUG
  qWarning("In QgsLegendLayerFileGroup::release");
#endif
  if(formerChild->type() == LEGEND_LAYER_FILE)
    {
      QgsLegendLayer* ll = dynamic_cast<QgsLegendLayer*>(parent());
      if(ll)
	{
	  ll->updateIcon();
	  ll->updateCheckState();
	}
    }
}