Boolean field

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EPrints 3 Reference: Directory Structure - Metadata Fields - Repository Configuration - XML Config Files - XML Export Format - EPrints data structure - Core API - Data Objects


Metadata Fields: Arclanguage - Base64 - Bigint - Boolean - Compound - Counter - Dataobjref - Date - Decimal - Email - Fields - Float - Id - Idci - Image - Int - Itemref - Keywords - Langid - Longtext - Longtext_counter - Multilang - Multipart - Name - Namedset - Pagerange - Recaptcha - Relation - Search - Secret - Set - Storable - Subject - Subobject - Text - Time - Timestamp - Url - Uuid


Description

Describes a simple yes/no value. Unless the field has the required property set, it can actually have a third setting of unset. This can be useful as it distinguishes between a "False" and a "don't know/haven't filled this in yet". For example when asking if a paper is refereed, this is a boolean field. However it's not required as often someone isn't sure, and does not want to click "no" when that's not necessarily true.

Inheritance

Additional Properties

Name Default Value Required Description Notes
input_style checkbox NO This controls how the field is rendered in input forms. May be one of menu, radio or checkbox.
input_rows n/a NO Number of rows for select box in input form. Only applicable if input_style => 'menu'. If so, must be configured within field definition.
false_first 0 NO Whether the false option should appear before the true option.

Required Phrases

In addition to the standard metadata field phrases:

menu style

If you use input_style=>"menu" then you need two phrases of the type:

datasetid + "_fieldopt_" + fieldname + "_TRUE"
datasetid + "_fieldopt_" + fieldname + "_FALSE"

These control the display of the items in the menu.

Example:

   <epp:phrase id="eprint_fieldopt_myboolean_TRUE">Certainly!</epp:phrase>
   <epp:phrase id="eprint_fieldopt_myboolean_FALSE">No way!</epp:phrase>

optional phrase to replace 'UNSPECIFIED' text

To overwrite the default 'UNSPECIFIED' option displayed when a boolean field is not required, a phrase with an underscore at the end can be used:

datasetid + "_fieldopt_" + fieldname + "_"

Example:

   <epp:phrase id="eprint_fieldopt_myboolean_">Don't know.</epp:phrase>

radio style

This uses a single phrase with two pins in it to indicate the locations of the radio buttons. The phrase id is:

datasetid + "_radio_" + fieldname

We suggest placing a <label> element around the radio button and it's title - as well as being good practice, this also means that in some browsers clicking on the text will select the button.

For example:

   <epp:phrase id="eprint_radio_myboolean"><label><epc:pin name="true"/>Yes, I like cheese.</label>
<label><epc:pin name="false"/>No, cheese is bad.</label></epp:phrase>

Database

Boolean fields are stored in the database as

fieldname VARCHAR(5)

API

See API page.

In the code these fields are stored as strings containing TRUE, FALSE or undef if they are not set.

Examples

Most basic example. Display a checkbox as this is the default.

{ 
   name => "no_request_email_button",
   type => "boolean",
}

Display as radio group of options. Allows TRUE, FALSE and UNSPECIFIED but phrases uses will determine labelling of options displaye.

{
    name => 'refereed',
    type => 'boolean',
    input_style => 'radio',
},

Display as drop down list of options. Allows only TRUE or FALSE as required is set to true.

{ 
    name => 'is_artwork', 
    type => 'boolean', 
    required => 1, 
    input_style => 'menu',
},