How can I merge values from multiple fields into a hidden box field?

I have a form with multiple input fields, mostly "picked" dates and "selected" drop down list items. (See URL below)

I need to generate a dynamic QR code whose value reflects a merger of several of these fields (example - Date field1+List Selection 1+ List Selection 2)

My assumption (potentially erroneous) is if I'm able to stage these fields into a hidden box field and parse/merge them properly via scripting, then the contents of this hidden field could serve as input to the dynamic QR Code generating widget. 

Any help in this direction would be appreciated.

The data from multiple fields can be merged with a Form Calculation field. You can also hide that field and use it as a base for Dynamic QR Code generation widget field.

Example:

Result:

If you need any further assistance, please let us know.