See also HTML::FormHandler::Field for a description of the base field attributes.
The inheritance hierarchy of HTML::FormHandler Fields
DESCRIPTIONA form's fields are created from the 'has_field' and 'field_list' definitions. FormHandler processes the field lists and creates an array of HTML::FormHandler::Field objects. The ``type'' of a field determines which field class to use. The field class determines which attributes are valid for a particular field. A number of field classes are provided by FormHandler. You can customize the validation in your form on a per field basis, but validation that will be used for more than one field might be more easily handled in a custom field class.
Fields are accessed with "form->field('name')". Field errors are in "$field->errors".
If the 'field_name_space' is not set, fields will be loaded from the HTML::FormHandler::Field name space. If you provide a 'field_name_space' it will be searched before FormHandler. If you want to explicitly list the field's package, prefix it with a plus sign. The field_name_space plus the default name spaces 'HTML::FormHandler::Field' and 'HTML::FormHandlerX::Field' will be searched for fields.
has '+field_name_space' => ( default => 'MyApp::Form::Field' ); has_field 'name' => ( type => 'Text' ); # HTML::FormHandler::Field::Text has_field 'name' => ( type => '+My::FieldType' ); # My::Fieldtype has_field 'foo' => ( type => '+Foo' ); # MyApp::Form::Field::Foo or has_field 'foo' => ( type => 'Foo' ); # MyApp::Form::Field::Foo
The most basic type is ``Text'', which is usually a 'text' HTML element and a string data type. (If the type of a field is not specified, it will be set to 'Text'.) A ``Select'' field type is a HTML select element, and validates against the list of values provided in the 'options'. A ``Multiple'' type is like ``Select'' but it allows selecting more than one value at a time.
Many field classes contain only a list of constraints and transformations to apply. Some use the 'validate' method, which is called after the actions are applied. Some build a custom select list using 'build_options'.
There are two rough categories of Field classes: those that do extra processing and those that are simple validators. The 'Compound', 'Repeatable', and 'Select' fields are fields that are functional.
Field namesThe standard way to use FormHandler is with field names that match your database accessors. If you want to prepend the HTML field names with a name plus dot, you can set the form 'name' and use the 'html_prefix' flag. ``$name.'' will be stripped from the beginning of the HTML fields before processing by HFH, and will be added back in 'fif'. The field's 'html_name' convenience attribute will return this name for use in templates.
If you want the FormHandler field name to be different than the database accessor, set 'accessor' on your fields. (It defaults to the field name.) You could then use any name that you want for your field.
There are a number of name-related field attributes. The 'name' is the name used to identify this particular field in this fields array. The 'full_name' includes the names of all parents of this field, like 'address.street.streetname'. The 'html_name' is the same as the 'full_name' unless you have set the 'html_prefix' flag, in which case it includes the form name: 'myform.address.street.streetname'.
To retrieve a field by name, you can use either the full_name or a chain: "$form->field('address')->field('street')->field('streetname')" or: "$form->field('address.street.streetname')".
Creating custom fieldsSubclass a custom field from HTML::FormHandler::Field, or one of the existing subclasses. Almost everything that is done in a custom field class can also be done in a form. The advantage of a field class is that it can simplify declaration of often-repeated sets of attributes.
The simplest subclasses contain only a 'validate' routine or an 'apply' attribute, which is called by the base Field class from 'process'. Look at HTML::FormHandler::Field::Email, for example.
If the field's value will be an object instead of a simple scalar, such as a DateTime, and you want to use the transformed value to fill in the form, then you will also need a deflation or field class 'deflate' method to reformat the object into a form suitable for an HTML form field. See HTML::FormHandler::Manual::InflationDeflation for more info.
Some custom fields might only require setting certain attributes to defaults, such as the HTML::FormHandler::Field::Hour field, which set 'range_start' to 0 and 'range_end' to 23. A 'select' field might override the 'build_options' builder for the 'options' array, like HTML::FormHandler::Field::IntRange. A field may add additional attributes, such as 'label_format' in HTML::FormHandler::Field::IntRange, or set the 'required' message.
An alternative to new field classes for many field validations might be roles with collections of validations.
Other field packagesSome custom fields are supplied as CPAN packages, in the HTML::FormHandlerX name space.
Fields supplied by FormHandler
Basic FieldsAlthough there are a lot of fields provided (probably too many) a lot of them are ``convenience'' fields or ``name'' fields, where the main benefit is that the field type is a name that gives the main purpose of the field. Most of these fields could be replaced by a basic field with a bit of validation or some select options. A few of the fields are special purpose fields that won't be used very often.
The fields in this section are the basic fields, the commonly used fields that will be most often used in a form.
A string data type that will be formatted as an HTML text field. Has 'minlength' and 'maxlength' attributes.
A field formatted as a select element.
A field formatted as a checkbox. If not in params, will be forced to 'false' value by 'input_without_param' attribute (0 by default).
A hidden field.
A password field. The value is not re-displayed.
A textarea field. Has 'cols' and 'rows' attributes.
A file upload field that takes a filehandle or a Catalyst upload object (an object with a 'size' method).
A submit field.
A reset field.
Complex Fields (Compound and Repeatable)These fields are complex fields which contain a fair amount of special code. They do not map to a single HTML element; they contain multiple subfields.
A compound field is a field that has sub-fields. Compound fields can be created in two ways: 1) using a field class, 2) by declaration.
To create a compound field class, you must extend HTML::FormHandler::Field::Compound and use HTML::FormHandler::Moose to allow declaring fields:
package MyApp::Field::Duration; use HTML::FormHandler::Moose; extends 'HTML::FormHandler::Field::Compound'; has_field 'month' => (type => 'Integer'); has_field 'day' => ( type => 'Integer' ); has_field 'minutes' => ( type => 'Integer' );
Then in the form:
has_field 'my_duration' => ( type => '+Duration' );
To create a compound field by declaration, declare the containing compound field and subfields, prefixing the subfield names with the name of the containing compound field plus a dot:
package MyApp::Form; use HTML::FormHandler::Moose; extends 'HTML::FormHandler'; has_field 'duration' => ( type => 'Compound' ); has_field 'duration.month' => ( type => 'Integer' ); has_field 'duration.day' => ( type => 'Integer' ); has_field 'duration.year' => ( type => 'Integer' );
In an HTML form the name of the field must be the complete name with dots. The 'html_name' field attribute can be used to get this name, "$field->html_name".
A compound field can be used for a database relation that will have only one row (belongs_to or has_one). If the relation has a compound primary key, you may need to provide the primary key columns, either through hidden fields or by setting them in the "$form->value" hash before 'update_model' is called.
See also HTML::FormHandler::Field::Compound.
Repeatable fields are used for arrays of compound fields.
has_field 'addresses' => ( type => 'Repeatable' ); has_field 'addresses.address_id' => ( type => 'PrimaryKey' ); has_field 'addresses.street'; has_field 'addresses.city'; has_field 'addresses.country' => ( type => 'Select' );
The arrays will be built from arrays passed in the params, or from related ('has_many') rows in the database.
It is also used for arrays of single fields using the 'contains' keyword:
has_field 'tags' => ( type => 'Repeatable' ); has_field 'tags.contains' => ( type => '+Tag' );
See HTML::FormHandler::Field::Repeatable for more information.
Text FieldsFields subclassed from the Text field.
Positive or negative real value, formatted to two decimal places.
Date field that can be used by jQuery datepicker plugin.
A subclass of 'Date' with the ``%m/%d/%Y'' format.
Uses Email::Valid for validation.
Positive and negative integers. Can use range_start and range_end.
A positive integer field.
Float field that allows you to set size, precision, decimal_symbol, and decimal_symbol_for_db.
Compound FieldsFields subclassed from 'Compound'.
Compound field with possible subfields: years, months, weeks, days, hours, minutes, seconds, nanoseconds.
A compound field that requires you to provide the subfields that you want. (month/day/year/hour/minutes)
Checkbox FieldsFields that inherit from 'Checkbox'.
Checkbox that return 1 or 0.
Select FieldsFields that inherit from 'Select'.
Multiple select. Also sorts the selected options to the top of the select list.
SelectCSVA multiple select field for comma-separated values in the database. It expects database values like: '1,5,7'. The string will be inflated into an arrayref for validation and form filling, and will be deflated into a comma-separated string in the output value.
A field with three possible values: empty/0/1.
Integer select range field from 0-23.
Select field with range from 0-59.
An integer select field. Can set label format with 'label_format'.
Select field with range from 1 - 12.
Select field with range from 1 - 31.
Select field with month name labels, value 1-12.
Select field with range from 0-59.
A select field where the labels are the names of the week, and the values are 0-6.
Select field providing year list 5 years back and 10 years forward.
NoValue fieldsFields that inherit from 'NoValue'. None of these fields will provide a 'value' in the "$form->value" hashref.
Base class for fields that don't produce a 'value'.
Button field that is rendered by the Button widget.
Non-data field used for inserting HTML into the form. Probably now better handled by a Block or a rendering tag.
Example field for adding a repeatable element.
Example field for removing a repeatable element
For Bootstrap-style non-editable fields.
TextArea fieldsFields that inherit from 'TextArea'.
Password field. Sets 'noupdate' flag if empty and not required.
Password confirmation field.
Other fieldsThese fields inherit just from 'Field'.
A file field that does no processing. Most people probably want to use 'Upload' instead.
Hidden field that provides the primary key for Repeatable fields.
A Captcha field using GD::SecurityImage. Requires the use of the HTML::FormHandler::TraitFor::Captcha role, or similar code.
AUTHORFormHandler Contributors - see HTML::FormHandler
COPYRIGHT AND LICENSEThis software is copyright (c) 2016 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.