/ 
Data-MuForm-0.04
River stage one • 3 direct dependents • 3 total dependents
/ Data::MuForm::Field::Select

NAME

Data::MuForm::Field::Select - Select field

VERSION

version 0.04

DESCRIPTION

This is a field that includes a list of possible valid options. This can be used for select and multiple-select fields. The field can be rendered as a select, a checkbox group (when 'multiple' is turned on), or a radiogroup.

Because select lists and checkbox_groups do not return an HTTP parameter when the entire list is unselected, the Select field must assume that the lack of a param means unselection. So to avoid setting a Select field with the 'skip_fields_without_input' flag, it must be set to inactive, not merely not included in the submitted params.

options

The 'options' attribute returns an arrayref. (In FH it used to return an array.)

The 'options' array can come from a number of different places, but a coercion will reformat from one of the valid options formats to the standard arrayref of hashrefs.

From a field declaration

In a field declaration:

has_field 'opt_in' => ( type => 'Select',
   options => [{ value => 0, label => 'No'}, { value => 1, label => 'Yes'} ] );
From a coderef supplied to the field definition
has_field 'flim' => ( type => 'Select', methods => { build_options => \&flim_options );
sub flim_options {  <return options arrayref> }
From a form 'options_<field_name>' method or attribute
has_field 'fruit' => ( type => 'Select' );
sub options_fruit { <returns options arraryef> }
    OR
has 'options_fruit' => ( is => 'rw',
    default => sub { [1 => 'apples', 2 => 'oranges', 3 => 'kiwi'] } );

The 'attribute' version is mostly useful when you want to be able to pass the options in on ->new or ->process.

From a field class 'build_options' method

In a custom field class:

package MyApp::Field::WeekDay;
use Moo;
extends 'Data::MuForm::Field::Select';
....
sub build_options { <returns a valid options arrayref> }
From the database

The final source of the options array is a database when the name of the accessor is a relation to the table holding the information used to construct the select list. The primary key is used as the value. The other columns used are:

label_column  --  Used for the labels in the options (default 'name')
active_column --  The name of the column to be used in the query (default 'active')
                  that allows the rows retrieved to be restricted
sort_column   --  The name or arrayref of names of the column(s) used to sort the options

See also Data::MuForm::Model::DBIC, the 'lookup_options' method.

The options field should contain one of the following valid data structures:

ArrayRef of HashRefs

Each hash reference defines an option, with the label and value attributes corresponding to those of the HTML field. This is the only structure in which you can supply additional attributes to be rendered. This is the format to which the other accepted formats will be coerced.

[{ value => 1, label => 'one' }, { value => 2, label => 'two' }]]
ArrayRef

A list of key/value pairs corresponding to HTML field values and labels.

[ 1 => 'one', 2 => 'two' ]
ArrayRef containing one ArrayRef

Each item inside the inner ArrayRef defines both the label and value of an option.

[[ 'one', 'two' ]]

Customizing options

Additional attributes can be added in the options array hashref.

[{ value => 1, label => 'one', id => 'first' }, { value => 1, label => 'two', id => 'second' }]

You can also use an 'attributes' hashref to set additional renderable option attributes (compatible with FH).

[{ value => 1, label => 'one', attributes => { 'data-field' => { 'key' => '...' } } }]

Note that you should *not* set 'checked' or 'selected' attributes in options. That is handled by setting a field default.

has_field 'my_select' => ( type => 'Select', default => 2 );

You can also divide the options up into option groups. See the section on rendering.

Reloading options

If the options come from the options_<fieldname> method or the database, they will be reloaded every time the form is reloaded because the available options may have changed. To prevent this from happening when the available options are known to be static, set the 'do_not_reload' flag, and the options will not be reloaded after the first time

Sorting options

The sorting of the options may be changed using a 'sort_options' method in a custom field class. The 'Multiple' field uses this method to put the already selected options at the top of the list. Note that this won't work with option groups.

Other Attributes and Methods

multiple

If true allows multiple input values

size

This can be used to store how many items should be offered in the UI at a given time. Defaults to 0.

empty_select

Set to the string value of the select label if you want the renderer to create an empty select value. This only affects rendering - it does not add an entry to the list of options.

has_field 'fruit' => ( type => 'Select',
     empty_select => '---Choose a Fruit---' );

label_column

Sets or returns the name of the method to call on the foreign class to fetch the text to use for the select list.

Refers to the method (or column) name to use in a related object class for the label for select lists.

Defaults to "name".

active_column

Sets or returns the name of a boolean column that is used as a flag to indicate that a row is active or not. Rows that are not active are ignored.

The default is "active".

If this column exists on the class then the list of options will included only rows that are marked "active".

The exception is any columns that are marked inactive, but are also part of the input data will be included with brackets around the label. This allows updating records that might have data that is now considered inactive.

sort_column

Sets or returns the column or arrayref of columns used in the foreign class for sorting the options labels. Default is undefined.

If not defined the label_column is used as the sort condition.

as_label

Returns the option label for the option value that matches the field's current value. Can be helpful for displaying information about the field in a more friendly format.

no_option_validation

Set this flag to true if you don't want to validate the options that are submitted. This would generally only happen if the options are generated via javascript, and you would presumably have some other kind of validation.

error messages

Customize 'select_invalid_value' and 'select_not_multiple'. Though neither of these messages should really be seen by users in a properly constructed select.

Rendering

The 'select' field can be rendered as a 'select', 'radiogroup', and 'checkboxgroup'. You change the 'layout_type' from 'standard' (for select) to 'radiogroup' or 'checkboxgroup' in the render args.

Option groups can be rendered by providing an options arrays with 'group' elements containing options:

sub options_testop { [
    {
        group => 'First Group',
        options => [
            { value => 1, label => 'One' },
            { value => 2, label => 'Two' },
            { value => 3, label => 'Three' },
        ],
    },
    {
        group => 'Second Group',
        options => [
            { value => 4, label => 'Four' },
            { value => 5, label => 'Five' },
            { value => 6, label => 'Six' },
        ],
    },
] }

You can use the 'render_option' method to render the options individually in a template.

Database relations

Also see DBIC::MuForm::Role::Model::DBIC.

The single select is for a DBIC 'belongs_to' relation. The multiple select is for a 'many_to_many' relation.

AUTHOR

Gerda Shank

COPYRIGHT AND LICENSE

This software is copyright (c) 2017 by Gerda Shank.

This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.