Plugin-settings form field for chosing a user?

Question

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)

Answer 1

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' => array(AttributeType::Mixed, 'required'=>false),
                 );
}

Then create a settings.html like this:

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

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