- $rev_id = isset( $rev_id ) ? $rev_id : $row->rev_id;
- if ( $rev_id > $row->rev_id ) {
- $this->mForm->prevId[$rev_id] = $row->rev_id;
- } elseif ( $rev_id < $row->rev_id ) {
- $this->mForm->prevId[$row->rev_id] = $rev_id;
+ if ( isset( $rev_id ) ) {
+ if ( $rev_id > $row->rev_id ) {
+ $this->mForm->prevId[$rev_id] = $row->rev_id;
+ } elseif ( $rev_id < $row->rev_id ) {
+ $this->mForm->prevId[$row->rev_id] = $rev_id;
+ }