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And now, my problems and questions.
Problem 1: I have can set AT&T set as the default Provider. This properly constrains Device and Plan to a set that is associated with u_provider=AT&T. However, if you change the Provider to another value, I want Device and Plan Lookup Select Boxes to be regenerated with Reference Qualifier called again.
Problem 2 solved: I set no default Provider, and Allow None. I would expect this to de-constrain-ify the Device and Plan. Instead it seems to do a full constrain and allow none to show. Perhaps because it's looking for Vendor=None. I fixed this with a revision to u_db692_mobile_device_vendor()
I seem to have a problem between Client Scripts versus Script Includes. The Script Includes let you use current. to access the values on the form. The Client Scripts disallow current., and instead allow you to use g_form. to get the values on the form. But I cannot find any method to force recalculating the Reference Qualifier.
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