grid-override.html 에 아래 코드 추가

<script>
    SCGrid.prototype.$$defaultAttachmentPopup = SCGrid.prototype.defaultAttachmentPopup;
    SCGrid.prototype.defaultAttachmentPopup = function(data, item, provider)
    {
        var me = this,
        grpCd = item.grpCd,
        itemIndex = item.rowIndex,
        fieldName = item.dataField,
        editable = item.editable,
        sharedGroupFieldName = me.getColumnElByName(fieldName).sharedGroupField;
        
        _openAttachPopup = function(attachPopup)
        {
            var content = attachPopup.getWindowContent();
            content.__provider = provider;
            content.__grid = me;
            content.setParam({
                grpCd : grpCd,
                itemIndex : itemIndex,
                fieldName : fieldName
            });
            content.setUploadOptions({
                editable : editable
             });
            content.addEventListener("close", function(e){
                attachPopup.close();
            });
            
            content.addEventListener("saved-attach", function(e){
                var fileCount = e.detail.file_count,
                    itemIndex = e.detail.itemIndex,
                    fieldName = e.detail.fieldName,
                    grpCd = e.detail.grpCd,
                    data = {
                        fileCount : fileCount, itemIndex : itemIndex, fieldName : fieldName, grpCd : grpCd
                    }
                this.__provider.setCellValue(itemIndex, fieldName, fileCount);
                this.__provider.setCellValue(itemIndex, sharedGroupFieldName, grpCd);
                this.__grid.fire("upload-complete",data, {bubbles: false});
                attachPopup.close();
            });
            attachPopup.show();
        }
        
        var attachPopup = SCPopupManager.get('cc-attachment-popup');

        if (attachPopup)
        {
            _openAttachPopup(attachPopup);
        }
        else
        {
            me.domHost.importLink('ui/lib/custom/html/cc-attachment-popup.html', function (moduleId)
            {
                SCPopupManager.register("cc-attachment-popup", "cc-attachment-popup", 800, 340, {
                    modal: true,
                    maximizable: true
                });
                
                attachPopup = SCPopupManager.get('cc-attachment-popup');
                _openAttachPopup(attachPopup);
            });
        }
    }
</script>