How to update data from imdistline function?

In GUIDE , how is it possible to get the updated data (distance) from imdistline function by using 'addNewPositionCallback'. How it works? In my image when I tried to get the distance value it shows only one default value. It is not showing updated position value when the position of the line is changed.

Thanks

Answer 1

[Image Analyst]

I would not mess with addNewPositionCallback. Just have a button for the user that says "Measure distance" and in that button's callback, just call imdistline() or improfile().