Which widget is this. It does not look like the OTB Measurement widget or Tom's custom Measure widget...?
you can just check the dom for a specific class name assuming it is using css class to change the look.
https://dojotoolkit.org/reference-guide/1.7/dojo/hasClass.html
If you are unable to get a handle to the dom, you can try using https://dojotoolkit.org/reference-guide/1.9/dojo/query.html