如何选择下拉菜单，点击下拉用的Watir项目的webdriver

Question

我的代码，点击下拉：

browser.select_list(:class => "ui-select-match").click 

我的代码从列表中选择：

browser.select_list(:name => "system-parameter").clear 
puts browser.select_list(:name => "system-parameter").options 
browser.select_list(:name => "system-parameter").select("Brand") 

HTML点击下拉菜单上：

<div class="ui-select-match" ng-hide="$select.open" ng-disabled="$select.disabled" ng-class="{'btn-default-focus':$select.focus}" placeholder="Select System Parameter"> 
    <span tabindex="-1" class="btn btn-default form-control ui-select-toggle" aria-label="Select box activate" ng-disabled="$select.disabled" ng-click="$select.activate()" style="outline: 0;"> 
    <span ng-show="$select.isEmpty()" class="ui-select-placeholder text-muted ng-binding">Select System Parameter</span> 
    <span ng-hide="$select.isEmpty()" class="ui-select-match-text pull-left ng-hide" ng-class="{'ui-select-allow-clear': $select.allowClear &amp;&amp; !$select.isEmpty()}" ng-transclude=""> 
    <span class="ng-binding ng-scope"></span> 
    </span> <i class="caret pull-right" ng-click="$select.toggle($event)"> 
    </i> <a ng-show="$select.allowClear &amp;&amp; !$select.isEmpty()" aria-label="Select box clear" style="margin-right: 10px" ng-click="$select.clear($event)" class="btn btn-xs btn-link pull-right ng-hide"> 
    <i class="glyphicon glyphicon-remove" aria-hidden="true"> 
    </i> 
    </a> 
    </span> 
    </div> 

HTML代码，从列表中选择：

<a href="javascript:void(0)" class="ui-select-choices-row-inner" uis-transclude-append=""> 
<div ng-bind-html="constant.Value | highlight: $select.search" name="Brand" class="ng-binding ng-scope">Brand</div> 
</a> 

<a href="javascript:void(0)" class="ui-select-choices-row-inner" uis-transclude-append=""> 
<div ng-bind-html="constant.Value | highlight: $select.search" name="Group" class="ng-binding ng-scope">Group</div> 
</a> 

<a href="javascript:void(0)" class="ui-select-choices-row-inner" uis-transclude-append=""> 
<div ng-bind-html="constant.Value | highlight: $select.search" name="Unit" class="ng-binding ng-scope">Unit</div> 
</a> 

我想单击下拉列表并且不能从列表中选择。