Link Widget in Drupal 7 Custom Forms
Via Will Vedder: if you want to embed a link widget (with Title and URL fields) in a form, you can do something like this (in your code that uses the Form API to build the form):
$form['my_link']() = array(
'#type' => 'link_field',
'#title' => t('CTA Link'),
'#description' => t('Optional Call to Action link.'),
'#field_name' => 'link_field',
'#field_parents' => array(),
'#language' => 'und',
'#delta' => 0,
);
That is different from simply rendering a link in the form:
$form['my_link']() = array(
'#type' => 'link',
'#title' => t('Example link'),
'#href' => 'http://foo.com',
);