<form {{action "add" on="submit"}}>
  <div class="input-group">
    {{input type="text" value=addInput placeholder=placeholder class="form-control"}}
    <div class="input-group-btn">
      {{#if checking}}
        <button class="btn btn-primary btn-disabled"><i class="icon icon-spinner icon-spin"></i></button>
      {{else}}
        <button class="btn btn-primary" {{action "add"}}><i class="icon icon-plus"></i></button>
      {{/if}}
      {{#if showDropdown}}
        <button type="button" class="btn btn-default dropdown-toggle" data-toggle="dropdown" aria-expanded="false"><span class="caret"></span></button>
        <ul class="dropdown-menu dropdown-menu-right" role="menu" style="min-width: 250px; max-height: 300px; overflow-y: auto;">
          <li role="presentation" class="dropdown-header">{{dropdownLabel}}</li>
          {{#if dropdownLoaded}}
            {{#each dropdownChoices as |item|}}
              <li>
                <a {{action "addObject" item}}>
                  {{identity-block identity=item}}
                </a>
              </li>
            {{/each}}
          {{else}}
            <li role="presentation" class="dropdown-header">
              <i class="icon icon-spinner icon-spin"></i> Loading...
            <</li>
          {{/if}}
        </ul>
      {{/if}}
    </div>
  </div>
</form>
