Changing units of area in measure widget,after adding graphics to map

[istwebappbuilder3]

HI, robert

i have concern in measure widget,i want to change units of area,after the area calculation are added to map as graphic

for example i have measured area with miles,added it lable's to map, if i change the unit as kilometes from drop-down,the graphic on the map should be changed to kilometes.

https://community.esri.com/docs/DOC-3209-measure-widget-21-for-web-app-builder

im using above measure widget

[RobertScheitlin__GISP]

Currently, the graphic would have to be removed and re-added. The label will not update with a unit change.