QgsSymbolV2* QgsGraduatedSymbolRendererV2::symbolForValue( double value ) { for ( QgsRangeList::iterator it = mRanges.begin(); it != mRanges.end(); ++it ) { if ( it->lowerValue() <= value && it->upperValue() >= value ) { if ( it->renderState() ) return it->symbol(); else return NULL; } } // the value is out of the range: return NULL instead of symbol return NULL; }