betweenGo

It is relatively simple to dynamically create a dropdown from which you can jump to different parts of a page using JavaScript and ATG DSPEL.

First create the dropdown.

<form name="jumpTo" action=".">
  <dspel:droplet name="/atg/dynamo/droplet/ForEach">
    <dspel:param name="array" param="categories"/>
    <dspel:setvalue param="category" paramvalue="element"/>
    <dspel:oparam name="outputStart">
      <select name="names">
    </dspel:oparam>
    <dspel:oparam name="output">
      <dspel:getvalueof id="index" param="index"/>
      <c:set var="catShortName" value="cat${index}"/>
      <option value="<c:out value="${catShortName}"/>">
        <dspel:valueof param="category.name"/>
      </option>
    </dspel:oparam>
    <dspel:oparam name="outputEnd">
      </select>
    </dspel:oparam>
  </dspel:droplet>
</form>

Next create the button outside of the form for jumping to different parts of the page. I learned about the window.location.hash from this article. And I learned about how to access the selected value from the dropdown from this article.

 <input type="image" src="/img/buttons/update.gif"
   onClick="window.location.hash=
document.jumpTo.names.options[document.jumpTo.names.selectedIndex].value">

Finally you create the name anchors throughout your document.

<dspel:droplet name="/atg/dynamo/droplet/ForEach">
  <dspel:param name="array" param="categories"/>
  <dspel:setvalue param="category" paramvalue="element"/>
  <dspel:oparam name="output">

    <%-- magazine category --%>
    <dspel:getvalueof id="index" param="index"/>
    <c:set var="catShortName" value="cat${index}"/>
    <a name="<c:out value="${catShortName}"/>"
       id="<c:out value="${catShortName}"/>">
      <dspel:valueof param="category.name"/>
    </a>

  </dspel:oparam>
</dspel:droplet>

Related posts:

1. Unobtrusive JavaScript
2. Comparison of DSP and DSPEL
3. ATG ForEach Output with Separators Between Items
4. How to Set an Array Property in an ATG Form
5. Accessing RepositoryItems with JSTL