[Chameleon] Visualize selected/queried layer

[Bart van den Eijnden]

What's even easier than using SLD (SLD will work mainly for WMS layers) would be just copying your layer with Mapscript, changing the symbology to a selection color, and setting the filteritem and filter. Here's some example code for that:

    $oMap = $oMapSession->oMap;

    // if selection layer exists, delete it first
    for ( $i=0; $i<$oMap->numlayers;  $i++ )
    {
      $oTempLayer = $oMap->getlayer($i);
      if ( $oTempLayer->name == 'StraGISWebSelection' )
      {
        $oTempLayer->set( 'status', MS_DELETE );
        break;
      }
    }

    $szLayerName = "";
    if (isset($HTTP_FORM_VARS["LAYER_NAME"]))
      $szLayerName = $HTTP_FORM_VARS["LAYER_NAME"];

    $szFilter = "";
    if (isset($HTTP_FORM_VARS["LAYER_FILTER"]))
      $szFilter = $HTTP_FORM_VARS["LAYER_FILTER"];

    $szSelectionColor = "";
    if (isset($HTTP_FORM_VARS["SELECTION_COLOR"]))
      $szSelectionColor = $HTTP_FORM_VARS["SELECTION_COLOR"];

    $arSelectionColor = explode(",", $szSelectionColor);

    $szSelectionWidth = "";
    if (isset($HTTP_FORM_VARS["SELECTION_WIDTH"]))
      $szSelectionWidth = $HTTP_FORM_VARS["SELECTION_WIDTH"];

    for ($i=0; $i<$oMap->numlayers; $i++)
    {
      $oLayer = $oMapSession->oMap->GetLayer($i);
      if ($oLayer->name == $szLayerName)
      {
        // copy layer
        $oSelectionLayer = ms_newLayerObj( $oMap, $oLayer );
        // move selection layer to top!
        while ($oMap->moveLayerDown($oSelectionLayer->index) != 0)
        {
          ;
        }
        $oSelectionLayer->set( 'name', 'StraGISWebSelection' );
        $oSelectionLayer->set( 'template', '' );
        
        if ($oSelectionLayer->connectiontype == MS_POSTGIS)
        {
          // BEN, 13-09-2005, for PostGIS, filter item does not work
          $oSelectionLayer->setFilter($oSelectionLayer->filteritem.'='.$szFilter);
        }
        else
        {
          $oSelectionLayer->setFilter($szFilter);
        }
        // set color to selection color
        for( $j=0; $j < $oSelectionLayer->numclasses; $j++)
        {
          $oClass = $oSelectionLayer->getClass($j);
          for ($k=0;$k<$oClass->numstyles;$k++)
		  {
            if ($oSelectionLayer->type == MS_LAYER_POLYGON)
            {
              $oClass->deletestyle($k);
            }
            else
            {
              $oStyle = $oClass->getStyle($k);
              $oStyle->color->setRGB( $arSelectionColor[0], $arSelectionColor[1], $arSelectionColor[2] );
              $oStyle->outlinecolor->setRGB( 0,0,0 );
            }
          }
          if ($oSelectionLayer->type == MS_LAYER_POLYGON)
          {
            // add a new style
            $oStyle = ms_newStyleObj( $oClass );
            $oStyle->set("symbolname", "circle");
            $oStyle->set("size", $szSelectionWidth);
            $oStyle->outlinecolor->setRGB( $arSelectionColor[0], $arSelectionColor[1], $arSelectionColor[2] );
          }
        }
        $oSelectionLayer->set( 'status', MS_ON );
      }
    } 

Best regards,
Bart

Bart van den Eijnden
Syncera IT Solutions
Postbus 270
2600 AG  DELFT

tel.nr.: 015-7512436
email: BEN at Syncera-ITSolutions.nl

>>> "Davelaar, Hilbert" <Hilbert.Davelaar at wur.nl> 19-9-2005 10:54:48 >>>
Hi Bart,
 
I don't have any experience with SLD, and though you mentioned the ExpressionBuilder widget as a reference, I can't find any example code. You know where exactly I can find some introductory code into the use of SLD for those purposes?
 
Kind regards,
Hilbert

	-----Oorspronkelijk bericht----- 
	Van: chameleon-bounces at lists.maptools.org namens Bart van den Eijnden 
	Verzonden: ma 19-9-2005 9:38 
	Aan: chameleon at lists.maptools.org; Davelaar, Hilbert 
	CC: 
	Onderwerp: Re: [Chameleon] Visualize selected/queried layer
	
	

	Hilbert,
	
	you can do this with SLD, it will require some programming though and a map refresh each time, you can look at the ExpressionBuilder widget for example code.
	
	Best regardas,
	Bart
	
	Bart van den Eijnden
	Syncera IT Solutions
	Postbus 270
	2600 AG  DELFT
	
	tel.nr.: 015-7512436
	email: BEN at Syncera-ITSolutions.nl 
	
	>>> "Davelaar, Hilbert" <Hilbert.Davelaar at wur.nl> 19-9-2005 9:29:18 >>>
	Hi list,
	
	I want to have certain functionality in my Chameleon application, but I'm wondering if it's possible. Maybe someone can tell me to stop trying to implement it or give me a way to do it.
	
	I have a polygon layer in my mapfile. Using the query widget the user is able to query this layer. But now I want to visualize the polygonfeature the user has queried, so after he has clicked he still can see to which polygon the query results apply. For example by another outline of this polygon or another color. It would be great if this is possible.
	
	Same thing I want to implement for te QuickZoom widget. From this widget the user is able to zoom to a polygon. It is possible then to show the user which is the polygon he zoomed at, instead of the fact that he has to assume its the polygon in the center of the map?
	
	Kind regards,
	Hilbert Davelaar
	
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