Fix #9148 (data-defined label positions with postgis)

A bit strangely, conversion of null variant with double type to a double value is considered ok by QVariant
qgis · Jun 11, 2014 · 863a83b · 863a83b
1 parent 54e6716
commit 863a83b
Showing 1 changed file with 4 additions and 2 deletions.
diff --git a/src/core/qgspallabeling.cpp b/src/core/qgspallabeling.cpp
@@ -2113,13 +2113,15 @@ void QgsPalLayerSettings::registerFeature( QgsFeature& f, const QgsRenderContext
 
   if ( dataDefinedEvaluate( QgsPalLayerSettings::PositionX, exprVal ) )
   {
-    xPos = exprVal.toDouble( &ddXPos );
+    if ( !exprVal.isNull() )
+      xPos = exprVal.toDouble( &ddXPos );
     QgsDebugMsgLevel( QString( "exprVal PositionX:%1" ).arg( xPos ), 4 );
 
     if ( dataDefinedEvaluate( QgsPalLayerSettings::PositionY, exprVal ) )
     {
       //data defined position. But field values could be NULL -> positions will be generated by PAL
-      yPos = exprVal.toDouble( &ddYPos );
+      if ( !exprVal.isNull() )
+        yPos = exprVal.toDouble( &ddYPos );
       QgsDebugMsgLevel( QString( "exprVal PositionY:%1" ).arg( yPos ), 4 );
 
       if ( ddXPos && ddYPos )