Thank you for the clarification. Previous messages on the list seemed to imply that IS_NOT_IN_DB would also be represented as a dropdown, but glad to know I made the correct choice in the end.
Cheers! On Feb 5, 9:43 am, DenesL <[email protected]> wrote: > The default widget for a field with an IS_NOT_IN_DB requires is a text > box. > Your interpretation of how it should work is just one of possibly > many. > Think of it this way, the values in the db are a definite set, so you > can create a list to choose one or many among them; the values that > are not part of the db yet may not defined and can possibly be > infinite e.g. books, stars, etc., so you can not list them. > > In your case the db has all possible values but web2py does not know > this. > The solution is to use the complement of the set, all_booths minus > leased_booths = free_booths, which is what you did. > > On Feb 4, 2:19 pm, SethKinast <[email protected]> wrote: > > > > > > > > > Hi, > > > First off, I've already fixed my problem by coding it differently. > > However, I was curious as to the proper way to set up this validator > > so it shows a dropdown. > > > I have two models, which can be simplified to: > > > db.define_table('booth', > > > Field('name','string',length=10,required=True,notnull=True,unique=True)) > > db.define_table('lease', > > Field('booth',db.booth), > > Field('end_date','date')) > > > When creating a new "lease", the SQLFORM field to pick a "booth" to > > attach should only show booths which have no lease. So I added this in > > the controller: > > > def new(): > > db.lease.booth.requires = IS_NOT_IN_DB(db(db.lease.end_date == > > None)),'lease.booth') > > > This promptly transformed the booth dropdown into a text box. It > > worked fine if, when testing, I used IS_IN_DB instead (showing only > > booths with current leases, which is of course backwards, but it > > showed them as a dropdown). I know that if you put the validators in a > > list they will not create dropdowns, and I made sure that my validator > > was not in a list. > > > So instead I switched to this: > > > def new(): > > leased_booths = db(db.lease.end_date == > > None)._select(db.lease.booth) > > db.lease.booth.requires = > > IS_IN_DB(db(~(db.booth.id.belongs(leased_booths))),'booth.id','% > > (name)s') > > > which is a bit less efficient but displays the desired behavior. Is > > there a more "web2py"-ish way to accomplish this, or is IS_NOT_IN_DB > > not supposed to display a dropdown? From my reading of the > > documentation, I thought it was supposed to do so.
