public function offsetSet($index, $value)
    {
        if (!parent::offsetExists($index)) {
            throw new PropertyReadOnlyException($index, __CLASS__);
        }

        parent::offsetSet($index, $value);
    }
public function offsetSet($index, $value)
    {
        if (!parent::offsetExists($index)) {
            throw new PropertyReadOnlyException($index, __CLASS__);
        }

        parent::offsetSet($index, $value);
    }
public function offsetSet ( $ index , $ value ) { if ( ! parent :: offsetExists ( $ index ) ) { throw new PropertyReadOnlyException ( $ index , __CLASS__ ) ; } parent :: offsetSet ( $ index , $ value ) ; }
Only allows existing indexes to be updated.

This is so that only settings specified by a field type can be set.

@throws \eZ\Publish\API\Repository\Exceptions\PropertyReadOnlyException On non existing indexes

@param string|int $index
@param mixed $value
Only allows existing indexes to be updated .