The contour threshold textbox and histogram slider don't work together (ContourSurface plugin) #495
Description
Setting a value in the "Contour Selection" field of the interface (textbox) and reapplying doesn't create a surface with the modified value, rather the value on the histogram slider is used. Changing the slider value and reapplying does work however (and it changes the textbox value with it).
This can be solved by either changing the textbox to a label to express the fact that it can't be used as an input or by linking the textbox with the histogram so that if the textbox is changed, the slider changes with it.
