Forum OpenACS Q&A: ad_form select fields howto

For instance, the following creates a form and initializes the date widget to today:

set now [db_string now_str "select to_char(current_timestamp,'YYYY-MM-DD') from dual"]

ad_form -name test_form -form {
  my_table:key
  {name:text(text) {label "Name"} {html {size 50}}}
  {start_date:date {label "Start Date"} {value $now}}
} -validate {
  {start_date {start_date:date} }
}
...etc...

But while this successfully flags the date field with an appropriate message ("The day must be between 1 and 30 for the month of September") when you set the widget to "31 September 2002", it dies ugly when a correct date is passed in:

Request Error

       syntax error in expression "start_date:date"
           while executing
       "expr start_date:date"
           ("uplevel" body line 1)
           invoked from within
       "uplevel #$level [list expr $validate_expr"
           (procedure "ad_form" line 455)
...etc...

I was hoping for some good examples in other packages, but none of them (other than survey and acs-person) seem to use ad_form yet, and those don't use dates. News does use dates of course but not ad_form. Furthermore, it interestingly only checks for a valid interval and happily allows a user to enter a bogus "publish date" -- and then barfs ugly with a Request Error (not a more graceful ad_return_error) when [clock scan] can't parse the date.

So, is there a simple syntax that I'm missing here, or does the issue involve the "to_sql", "from_sql" and "to_html" stuff that I haven't yet figured out either? Many TIA!

I'll try to improve the documentation on this a bit.  The inline documentation tends to assume you know how the form builder works, but as more and more people start using ad_form without having extensively used the templating system's form builder in the past this assumption's not going to hold.

In this case, it is the templating system's form builder, not ad_form, which calls the data type's validation function automatically.  If you haven't used the form builder before, there's no way you'd know that from just reading ad_form's docs ...

Who would like to write it?

And yes, you did hear correctly, ad_form is a nice wrapper around the template system form builder.  If necessary, you can intermix the template system form-builder commands with ad_form.