I'm developing a system where users can set up a reminder to send to their contacts. They can have a number of custom defined date fields for the contacts. They need to enter an Operator (On/Before/After) a particular field (Anniversary/Birthday/etc) and optionally a quantity and unit of time if before or after are selected (4 Days/Weeks/Months).
It has been suggested that we do this by using a kind of sentence structure so that the user starts by seeing this:
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If they then select Before or After in the first box it changes to this:
This feels wrong to me as it would involve the On/Before/After drop down shifting left or right when the users selects a particular option. I'd like to suggest a better solution but am struggling to think of one. Any ideas?