Re: Thoughts on a CDBI::AsForm::_to_new()

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looks nice. I'll try it when as soon as I get the time too. It would be
really usefull to incorporate such a thing in AsForm if the problem of
the name clashes can be solved.

Mybe a better solution then prefixing the fields with the table name
would be to prefix the fields with the fieldname of the referencing
table. Otherwise you get the same problem if more then one field
references the same table. (For example if a person-class references two
phone-numbers, a private and an office number).

To simplify the formating of the resulting form via css, a class or id
attribute should be set, probably the plain fieldname as a class
attribute is a wise decission, so thata css-rule can be defined for all
the phoen number-fields.


Peter Speltz wrote:
| --- Andreas Fromm <Andreas.Fromm@xxxxxx.xxxxxxxxxxxx.xx> wrote:
|
|
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|>Ithink what Peter is trying to do, is what I'm also trying to do. If you
|>have the following structure:
|>
|>table person:
|>~   id serial
|>~   name text
|>~   adress integer references addresses
|>~   phone integer references phones
|>
|>table addresses
|>~   id serial
|>~   street text
|>~   number text
|>~   city text
|>~   zip text
|>
|>tabel phones
|>~   id serial
|>~   area text
|>~   number text
|>
|>- -----------
|>MyClass::Person
|>
|>__PACKAGE__->set-up-everything
|>__PACKAGE__->has_a ( adress => MyClass::Addresses )
|>__PACKAGE__->has_a ( phone => MyClass::Phones )
|>
|>- -----------
|>CDBI::AsForm will make a form for person with select-boxes for address
|>and phone, and what Perter (and I) would like to have is a form
|>containing input-boxes for the fields from person, addresses and phones.
|>Peter maybe asked for some extramagic of inserting default values for
|>the non-referencing fields of person (didn't understand that part
|>either). This is the reason why I don't use AsForm.
|>
|>I have been playing around with something like this a bit, but didn't
|>found the time to finish it up. It would be nice to include something
|>like this in AsFrom. My idea was to prefix the field names with the
|>table name the fields belong to, such as the field 'name' would become
|>'person.name', 'street' => 'address.street' and so on. Maybe
|>CDBI::FromCGI could be tweeked to process that kind of requests
|>properly, but I never looked at FromCGI in more detail then the
description.
|>
|
|
| That's exactly it.  With a CDBI system with AsForm, the computer
already knows
| how to make these inputs. All it needs is for a class to tell it:
"HEY, instead
| of giving me a select box to choose an address, give me inputs to
create a new
| address (the result of address->to_cgi or something).  Basically, in
its rawest
| form, this functionality comes just by making to_cgi call its self
with the
| has_a class when signaled to and put a hashref in the relevant column
slot
| instead of a single HTML::whatever object. I tried it but the
recursive call
| failed.
|
| There are some some issues. As Andreas said, column name clashes become a
| problem.
|
|  I ended up making a system with two parts  that lives in my own classes--
|
| 1) "has_a_new_inputs"  -- a part to generate other inputs for columns in a
| class that are foreign keys , which lives in my base model class.
|
| 2)"has_a_new" --  a method to tell "has_a_new_inputs" what foreign
keys I want
| other inputs for, and further more what columns from that foreign
class i want
| inputs for.  This is specified in each end user class.
|
| Attached is the code and a full synopsis. I still haven't figured out
what to
| do about field name clashes so I just make sure i don't have any.
|
| I hope this is clear enough. I bet  AsForm could incorporate this
| functionality. I made a feeble attempt at putting the has_a_new_inputs
code
| into AsForm::_to_new_inputs (new is a keyword in Template Toolkit and
won't
| work as a parameter). Then modifying AsForm::to_field to recognize a
new_inputs
| parametr. Then i could say:
|
| # get hashref of HTML::whatever objects instead of a single one.
| my $addr_inputs = Person->to_field("address_id", "new_inputs").
|
| I'll try again as a proof of concept.
|
|
| thanks
|
|
|
| =====
| pjs
|
| __________________________________________________
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|
| ------------------------------------------------------------------------
|
|
| # expand foreign keys in a CDBI class to inputs for columns of the
foreign class
| # using AsForm methods.
|
| # TODO make this more robust
| sub BaseCDBI::has_a_new_inputs {
|     my ($self, $r) = @_;
|     return 0 unless $self->can("has_a_new");
|     my $has_a_new_cols = $self->has_a_new;  # HAS_A_NEW called here
|
|     foreach my $col (keys %$has_a_new_cols)
|     {
|         my ($has_a_class, @input_cols) = @{$has_a_new_cols->{$col}};
|
|         unless ($has_a_class->can('to_field') ) {
|             warn "Class: $has_a_class can't to_field. Needs AsForm.";
| 	    next;                                     	
|         } # sanity check
|
|         my %res = map { $_ => $has_a_class->to_field($_) }  @input_cols;
|         $result{$col} =  \%res;
|     }
|     return  \%result;
| }
|
|
| sub Person::has_a_new {
|     { address_id => [ qw/Address street number city state zip/ ] },
|     { phone_id   => [ qw/Phone area number/]
| };
|
|
|
|
| Synopsis:
|
| package Person;
| Person->has_a(address_id => "Address");
| Person->has_a(phone_id   => "Phone");
|
| # specify class and columns of that class you want inputs for in place
of an
| # input for the key column. Class spec won't be necessary in finished
version
| sub has_a_new {
|     { address_id => [ qw/Address street number city state zip/ ] },
|     { phone_id   => [ qw/Phone area number/]
| };
|
| # then in some near by code
|
| $template_args{cgi_inputs} = Person->to_cgi;
| my $other_inputs = Person->has_a_new_inputs;  #
| $template_args{other_inputs} = $other_inputs
|
| # then in a new_person  TT template
|
| [% FOREACH $col IN cgi_inputs.keys;
|      IF other_inputs.$col; # insert other inputs instead of to_cgi default
| 	other_cols = other_inputs.$col; # stupid to lookup again
|         FOREACH mycol IN other_cols.keys;
|            "<label> $mycol </label>" other_cols.$mycol.as_XML;
|         END;
|         NEXT;
|      END;
|
|      "<label> $col </label>" cgi_inputs.$col.as_XML;
|
|   END;
| %]
|
|

- --
Grüße,

Andreas Fromm

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