protected function applyLegendConditions($attributeId, $activeLegendId)
    {
        // No conditions for legend defined.
        if (!isset($this->conditions[$activeLegendId])) {
            return;
        }

        if (!isset($this->conditions[$attributeId])) {
            $this->conditions[$attributeId] = new PropertyConditionChain();
        }

        $this->conditions[$attributeId]->addCondition($this->conditions[$activeLegendId]);
    }