Examples of Programmatic label

These are examples of the Programmatic label definition. The examples presented here are non-normative and not testable. They serve to illustrate some common pitfalls about the definition and to help implementers of ACT rules understand it.

Implicit labels

The input element is a labeled control of the label element (implicit label). Therefore the label element is a programmatic label of the input element.

<label>Full name: <input type="text" name="full_name" /> </label>

Explicit labels

The input element is a labeled control of the label element (explicit label). Therefore the label element is a programmatic label of the input element.

<label for="fname">Full name:</label> <input type="text" id="fname" name="full_name" />

Aria-labelledby, single reference

The span element is referenced by the aria-labelledby attribute on the input element. Therefore, the span element is a programmatic label of the input element.

<span id="label_fname">Full name:</span> <input type="text" name="full_name" aria-labelledby="label_fname" />

Aria-labelledby, multiple references

Both span elements are referenced by the aria-labelledby attribute on the input element. Therefore, each span element is a programmatic label of the input element.

<span id="billing">Billing</span>
<span id="address">address</span>
<input type="text" name="billing_address" aria-labelledby="billing address" />

Conflicting label methods

The span element is referenced by the aria-labelledby attribute on the input element and the input element is a labeled control of the label. Therefore, the span element and the label are each a programmatic label of the input element.

<span id="label_fname">Full name:</span>
<label>Full name: <input type="text" name="full_name" aria-labelledby="label_fname"/></label>

Invalid label for attribute

The div element is not labelable. Therefore, it is not a labeled control for the label element and the label element is not a programmatic label for the div element.

<label for="bond">Full name</label>
<div id="bond">My name is Bond. James Bond.</div>

aria-labelledby on div

The span element is referenced by the aria-labelledby attribute on the div element. Therefore, the span element is a programmatic label of the div element. Note that the aria-labelledby attribute works on any element, not just on the labelable elements.

<span id="label_fname">Full name:</span>
<div aria-labelledby="label_fname">My name is Bond. James Bond.</div>

Glossary

Programmatic label

Element L is a programmatic label of target element T if either:

• T is a labeled control of L; or
• L is referenced by ID in the aria-labelledby attribute of T.

Note: a given element may have more than one programmatic label.