Introduction
The field_select type field, part of the Settings API, allows the user to select a form field from a drop down.
Example
The following example shows a section with a field_select type field which has been limited to only include email type form fields.
array(
'title' => 'Field Select',
'fields' => array(
array(
'name' => 'email',
'label' => esc_html__( 'Email Field', 'sometextdomain' ),
'type' => 'field_select',
'required' => true,
'tooltip' => '<h6>' . esc_html__( 'Email Field', 'sometextdomain' ) . '</h6>' . esc_html__( 'Select which Gravity Form field will be used as the subscriber email.', 'sometextdomain' ),
'args' => array(
'input_types' => array( 'email' )
)
)
)
);
The code above will render a drop down similar to the following: