title: ZK Binding NotifyChange not work on onChanging Event?
body: <p>I currently use ZK for web-development. Here is my case:</p>
  
  <p>I implement instant search, once text change=> perform search.</p>
  
  <p><strong>Zul File</strong></p>
  
  <pre><code>    &lt;textbox id="textSearch" sclass="search_text"&gt;
                                          &lt;attribute name="onChanging"&gt;                                   
                          lbOnChangingSearch.setValue(event.getValue());
                                              vm.onChangingTextSearch();                                  
                                          &lt;/attribute&gt;
                                      &lt;/textbox&gt;
                                      &lt;label id="lbOnChangingSearch" visible="false"&gt;&lt;/label&gt;
  
          &lt;grid id="gridChapter" model="@load(vm.chapterInPage)"&gt; 
            ....
          &lt;/grid&gt;
  </code></pre>
  
  <p><strong>Controller code</strong></p>
  
  <pre><code>ListModelList&lt;ChapterJoinComic&gt; chapterInPage;
  public ListModelList&lt;ChapterJoinComic&gt; getChapterInPage() {
      return chapterInPage;
  }
  
  @NotifyChange({ "topComics", "chapterInPage"} )
  @Command
      public void onChangingTextSearch() {
  
          FilterObject fo = getFilterObject();
          fo.setSearch_str(lbOnChangingSearch.getValue());
  
          // 
          doSearch(fo); // Change chapterInPage
  
  
         // Manually post Not
   BindUtils.postNotifyChange(null,null,this.chapterInPage,"chapterInPage");  
      }
  </code></pre>
  
  <p><strong>Problem</strong>
  After call onChangingText search, Grid dont update databinding.
  But if I continue change text (more call onChangingTextSearch ). The Grid will update, but the updated value is the previous value. </p>
  
  <p>It seems the Grid is a-step slower than my latest Model object.</p>
  
  <p><strong>Note</strong> If I use onOK instead of onChanging event, the databinding works well.</p>
  
  <p>Anyone can help me. Thanks in advance!</p>