NAME¶
CGI::FormBuilder::Template - Template adapters for FormBuilder
SYNOPSIS¶
# Define a template engine
package CGI::FormBuilder::Template::Whatever;
use base 'Whatever::Template::Module';
sub new {
my $self = shift;
my $class = ref($self) || $self;
my %opt = @_;
# override some options
$opt{some_setting} = 0;
$opt{another_var} = 'Some Value';
# instantiate the template engine
$opt{engine} = Whatever::Template::Module->new(%opt);
return bless \%opt, $class;
}
sub render {
my $self = shift;
my $form = shift; # only arg is form object
# grab any manually-set template params
my %tmplvar = $form->tmpl_param;
# example template manipulation
my $html = $self->{engine}->do_template(%tmplvar);
return $html; # scalar HTML is returned
}
DESCRIPTION¶
This documentation describes the usage of
FormBuilder templates, as well
as how to write your own template adapter.
The template engines serve as adapters between CPAN template modules and
FormBuilder. A template engine is invoked by using the
"template" option to the top-level "new()" method:
my $form = CGI::FormBuilder->new(
template => 'filename.tmpl'
);
This example points to a filename that contains an "HTML::Template"
compatible template to use to layout the HTML. You can also specify the
"template" option as a reference to a hash, allowing you to further
customize the template processing options, or use other template engines.
For example, you could turn on caching in "HTML::Template" with
something like the following:
my $form = CGI::FormBuilder->new(
fields => \@fields,
template => {
filename => 'form.tmpl',
shared_cache => 1
}
);
As mentioned, specifying a hashref allows you to use an alternate template
processing system like the "Template Toolkit". A minimal
configuration would look like this:
my $form = CGI::FormBuilder->new(
fields => \@fields,
template => {
type => 'TT2', # use Template Toolkit
template => 'form.tmpl',
},
);
The "type" option specifies the name of the engine. Currently accepted
types are:
Builtin - Included, default rendering if no template specified
Div - Render form using <div> (no tables)
HTML - HTML::Template
Text - Text::Template
TT2 - Template Toolkit
Fast - CGI::FastTemplate
CGI_SSI - CGI::SSI
In addition to one of these types, you can also specify a complete package name,
in which case that module will be autoloaded and its "new()" and
"render()" routines used. For example:
my $form = CGI::FormBuilder->new(
fields => \@fields,
template => {
type => 'My::Template::Module',
template => 'form.tmpl',
},
);
All other options besides "type" are passed to the constructor for
that templating system verbatim, so you'll need to consult those docs to see
what all the different options do. Skip down to "SEE ALSO".
SUBCLASSING TEMPLATE ADAPTERS¶
In addition to the above included template engines, it is also possible to write
your own rendering module. If you come up with something cool, please let the
mailing list know!
To do so, you need to write a module which has a sub called
"render()". This sub will be called by
FormBuilder when
"$form->render" is called. This sub can do basically whatever it
wants, the only thing it has to do is return a scalar string which is the HTML
to print out.
This is actually not hard. Here's a simple adapter which would manipulate an
"HTML::Template" style template:
# This file is My/HTML/Template.pm
package My::HTML::Template;
use CGI::FormBuilder::Template::HTML;
use base 'CGI::FormBuilder::Template::HTML';
sub render {
my $self = shift; # class object
my $form = shift; # $form as only argument
# the template object (engine) lives here
my $tmpl = $self->engine;
# setup vars for our fields (objects)
for ($form->field) {
$tmpl->param($_ => $_->value);
}
# render output
my $html = $tmpl->output;
# return scalar;
return $html;
}
1; # close module
Then in
FormBuilder:
use CGI::FormBuilder;
use My::HTML::Template; # your module
my $tmpl = My::HTML::Template->new;
my $form = CGI::FormBuilder->new(
fields => [qw(name email)],
header => 1,
template => $tmpl # pass template object
);
# set our company from an extra CGI param
my $co = $form->cgi_param('company');
$tmpl->engine->param(company => $co);
# and render like normal
print $form->render;
That's it! For more details, the best thing to do is look through the guts of
one of the existing template engines and go from there.
SEE ALSO¶
CGI::FormBuilder, CGI::FormBuilder::Template::HTML,
CGI::FormBuilder::Template::Text, CGI::FormBuilder::Template::TT2,
CGI::FormBuilder::Template::Fast, CGI::FormBuilder::Template::CGI_SSI
REVISION¶
$Id: Template.pm 97 2007-02-06 17:10:39Z nwiger $
AUTHOR¶
Copyright (c) Nate Wiger <
http://nateware.com>. All Rights Reserved.
This module is free software; you may copy this under the terms of the GNU
General Public License, or the Artistic License, copies of which should have
accompanied your Perl kit.