Plugin-settings form field for chosing a user? I'd like to be able to select a user for a settings field for my plugin. 

Is there a settings AttributeType that matches users? And a corresponding forms template for picking a user? 

(also interesting would be picking assets/elements from a certain section)
Copying from the widgets settings I made something that sort of works: 

Define the setting to be type mixed: 

protected function defineSettings()
{
    return array(
                 'jobsemail' =&gt; array(AttributeType::Mixed, 'required'=&gt;false),
                 );
}


Then create a settings.html like this: 

{% import "_includes/forms" as forms %}

{% set userInput %}
    &lt;div class="select"&gt;
        &lt;select id="jobsemail" name="jobsemail"&gt;
          &lt;option value=""&gt;No one&lt;/option&gt;
            {% for user in craft.users.group('Admin') %}
          &lt;option value="{{ user.id }}"{% if user.id == settings.jobsemail %} selected{% endif %}&gt;{{ user.name|t }}&lt;/option&gt;
            {% endfor %}
        &lt;/select&gt;
    &lt;/div&gt;
{% endset %}

{{ forms.field({
    label: "Email recipient"|t,
    instructions: "This person gets emailed when new jobs are added"|t,
    id: 'jobsemail',
}, userInput) }}


This gives you a basic SELECT drop-down list. It's ok here, because the number of admin users is low. It would be less suitable if there were 100s of users. 

Is a better solution with a real pop-up element picker would be nice!