in reply to How do you use Template Toolkit with Dancer2?

Hello again. My question is to those familiar with Dancer2 (and Template Toolkit.) I'm new to these, as I am considering them as migration tools from CGI. I've been looking for information on how are classic form elements (e.g., radio groups, pull-down menus, check boxes, etc.) implemented. I have been unsuccessful in finding any examples. I am particularly interested in those that are dynamically populated with options from a database, a hash, or some other data structure. For example, using CGI one would write: 
 my $menu = popup_menu(-name=>'menu_name',
                         -values=>['eenie','meenie','minie'],
                         -default=>['meenie','minie'],
       -labels=>\%labels,
       -attributes=>\%attributes);

print $menu;

[download]
The content of the variable $menu could also then be used to fill a template "on-the-fly". Anyway, any suggestions or references to where I could glean such info would be greatly appreciated.

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Re^2: How do you use Template Toolkit with Dancer2?
by choroba (Cardinal) on Apr 26, 2022 at 10:13 UTC
    Using Template::Toolkit, create a template like this: 
    <select name="[% name %]" >
[%- FOR option IN options %]
<option [% FOREACH attr IN option.attributes.keys %][% attr %]="[% opt
+ion.attributes.$attr %]" [% END -%]
[%- IF option.default %]selected="selected" [% END -%]
value="[% option.value %]">[% option.label %]</option>
[%- END %]
</select>

    [download]

    In Dancer2 code, just call it with 

    return template 'menu',
    {name    => 'menu_name',
     options => [
         {value => 'eenie',  label => 'your first choice', attributes 
+=> {class => 'first choice'}},
         {value => 'meenie', label => 'your second choice', default =>
+ 1},
         {value => 'minie',  label => 'your third choice',  default =>
+ 1}],
     }

    [download]

    Update: Accept any attributes, not just class (not sure I'd recommend it).

    map{substr$_->[0],$_->[1]||0,1}[\*||{},3],[[]],[ref qr-1,-,-1],[{}],[sub{}^*ARGV,3]
[reply]
[d/l]
[select]

      Thank you for your suggestion.

      When I tried to encapsulate this code in a subroutine, and call it in another subroutine, Dancer2 seems to automatically use the main template located in the layout directory as a wrapper to this snippet, as well at to the entire page that generated an undesired visual effect. Ideally, it should be possible to write a simple subroutine that returns a menu, that, in turn can be invoked in some other subroutine that generates an arbitrary form: 
       sub dropdown_menu { # should generate only an HTML snippet of a menu
  #my ..arguments..;

 return  template 'form_menu.tt', { ...argument hash...  };
}
.
.
.

get '/' => sub { # generates the actual form that is used as [% conten
+t %] in the layout/main.tt template

  template 'some_form.tt', {
      menu1  => dropdown_menu(...parameters1...),
      menu2  => dropdown_menu(...parameters2...),
      radio1 => radio_group(...parameters3...),
      .
      . 
  }
}

      [download]
      Does that make sense, or am I accidentally breaking some Dancer2 paradigm? I apologize if this question is trivial.
[reply]
[d/l]
        Yes, you're breaking the Model - View - Controller paradigm. You can include the dropdown menu template from other templates, sending only the data from the code (i.e. no "dropdown_menu" in the code).

        map{substr$_->[0],$_->[1]||0,1}[\*||{},3],[[]],[ref qr-1,-,-1],[{}],[sub{}^*ARGV,3]
[reply]
[d/l]

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