Here is the latest update of the Measure Widget developed from the FlexViewer Draw Widget. It shows interactive segment measurements as you are drawing them. This is some functionality that was required by our planning department as they needed to show distances as they measured them and not after the drawing was complete.
You can also find this at ArcGIS Online at:
https://yakima.maps.arcgis.com/home/item.html?id=36a80475e5d740279854398d3f7b6d01
or at Github at: