/ 
Data-MuForm-0.04
River stage one • 3 direct dependents • 3 total dependents
/ Data::MuForm::Manual::Cookbook

NAME

Data::MuForm::Manual::Cookbook - Cookbook recipes for using MuForm

VERSION

version 0.04

NAME

Data::MuForm::Manual::Cookbook

RECIPES

Update all fields

In FormHandler you can do something like:

sub build_update_subfields {{
    by_flag => { contains => { wrapper_class => ['rep_elem'] } },
    by_type => { 'Select' => { wrapper_class => ['sel_wrapper'] },
                 'Boolean' => { element_class => ['sel_elem'] },
    },
}}

You can achieve the equivalent in MuForm with:

sub after_build_fields {
    my $self = shift;
    foreach my $field ( $self->all_repeatable_fields ) {
        $field->init_instance({ 'ra.wa.class' => ['rep_elem'] });
    }
    # the 'index' contains all fields, not just top level fields
    foreach my $field ( values %{$self->index} ) {
        if ( $field->type eq 'Select' ) {
            $field->render_args->{wrapper_attr}{class} = ['sel_wrapper'];
        }
        elsif ( $field->type eq 'Boolean' ) {
            $field->render_args->{element_attr}{class} = ['sel_elem'];
        }
    }
}

apply roles to fields

A role to overide the 'id' attribute. (Note: you can do this is in a built-in way with the 'build_field_id' form method, but this serves as an example.):

package My::DynamicFieldId;
use Moo::Role;
around 'id' => sub {
    my $orig = shift;
    my $self = shift;
    my $form_name = $self->form->name;
    return $form_name . "." . $self->full_name;
};

Apply to the fields in an 'after_build_fields' sub.

package My::CustomIdForm2;
use Moo;
use Data::MuForm::Meta;
extends 'Data::MuForm';

has '+name' => ( default => 'D123' );

has_field 'foo';
has_field 'bar';

sub after_build_fields {
    my $self = shift;
    # the 'index' contains all fields, not just top level fields
    foreach my $field ( values %{$self->index} ) {
        Role::Tiny->apply_roles_to_object($field, 'My::DynamicFieldId');
    }
}

Use an external validation method

The form package has an attribute to hold the coderef which will do the validation, which is called in a validate method.

package SignupForm;
use Moo;
use Data::MuForm::Meta;
extends 'Data::MuForm';

has check_name_availability => ( is => 'ro', required => 1 );

has_field 'name';
has_field 'email';

sub validate {
    my $self = shift;
    my $name = $self->value->{name};
    my $meth = $self->check_name_availability;
    if ( defined $name && length $name && !$meth->($name) ) {
        $self->field('name')->add_error('That name is taken already');
    }
}
1;

A non-form Perl application has a method to validate a field, such as checking in the database that a username is unique:

package MyApp::Signup;
use Moo;

has 'form' => ( is => 'ro', builder => 'build_form' );
sub build_form {
    my $self = shift;
    return SignupForm->new(
        {
            check_name_availability => sub {
                my $name = shift;
                return $self->username_available($name);
            },
        }
    );

}
sub username_available {
    my ( $self, $name ) = @_;
    return $name eq 'Sam' ? 1 : 0;
}
1;

Order fields from a role

Given a Moo::Role with fields:

package MyApp::Form::Role::MyFields;
use Moo::Role;
use Data::MuForm::Meta;

has_field 'r-one';
has_field 'r-two';
has_field 'r-three';

...And a Form class which includes those fields.

package MyApp::Form::TestRole;
use Moo;
use Data::MuForm::Meta;
extends 'Data::MuForm';

with 'MyApp::Form::Role::MyFields';

has_field 'f-one';
has_field 'f-two';
has_field 'f-three';
has_field 'f-four';

...Order the fields in an 'order_fields' sub in the form.

# put role fields between f-two and f-three
sub order_fields {
    my $self = shift;
    my @form_order = (1, 2, 6, 7, 8);
    my @role_order = (3, 4, 5);
    foreach my $field ( $self->all_fields ) {
        my $order;
        if ( $field->source eq __PACKAGE__ ) {
            $order = shift @form_order;
        }
        else {
            $order = shift @role_order;
        }
        $field->order($order);
    }
}

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.