title: zk element if @load equals condition
body: <p>I have a list which I build in zul file.</p>
  
  <pre><code>&lt;listbox id="someId" model="@load(vm.searchResults)" selectedItem="@bind(vm.selectedItem)" vflex="1" multiple="true"&gt;
      &lt;listhead&gt;
          &lt;listheader label="${labels.l1}" width="150px" align="center"/&gt;
          &lt;listheader label="${labels.l2}" width="150px" align="center"/&gt;
          &lt;listheader label="${labels.l3}" width="100px" align="center"/&gt;
      &lt;listheader label="${labels.l4}" width="400px" align="center"/&gt;
      &lt;/listhead&gt;
      &lt;template name="model"&gt;
          &lt;listitem style="text-align: left;"&gt;
              &lt;listcell style="word-wrap: break-word; text-align: left;"&gt;
                  &lt;label value="@load(each.l1)"/&gt;
              &lt;/listcell&gt;
              &lt;listcell style="word-wrap: break-word; text-align: left;"&gt;
                  &lt;label value="@load(each.l2)"/&gt;
              &lt;/listcell&gt;
              &lt;listcell style="word-wrap: break-word; text-align: left;"&gt;
                  &lt;label value="@load(each.l3)"/&gt;
                  &lt;a action="" label="should be displayed when some param is equals to 3 " if="{each.someParam=='3'}"/&gt;
              &lt;/listcell&gt;
              &lt;listcell style="text-align: left;"&gt;
                  &lt;label value="@load(each.l4)"/&gt;
              &lt;/listcell&gt;
          &lt;/listitem&gt;
      &lt;/template&gt;
  &lt;/listbox&gt;
  </code></pre>
  
  <p>I need to display <strong>a</strong> element when each some param is 3. How do I get it?</p>
  
  <pre><code>&lt;a action="" label="should be displayed when some param is equals to 3 " if="{each.someParam=='3'}"/&gt;
  </code></pre>
  
  <p>I checked this 
  <a href="https://stackoverflow.com/questions/15332500/how-to-use-if-some-condition-in-zk-template-tag">How to use if=&quot;some condition&quot; in ZK template tag</a></p>
  
  <p>But it did not help me.</p>
  
  <p>I also tried</p>
  
  <pre><code>&lt;a action="" label="should be displayed when some param is equals to 3 " if="{@(each.someParam)=='3'}"/&gt;
  </code></pre>
  
  <p>Did not work either. <strong>'3'</strong> or <strong>3</strong> does not change anything. If I remove <strong>if</strong> condition <strong>a</strong> element is displayed. But I want to display it only when it meets if condition.</p>
  
  <p>Please help me</p>