title: How to limit Visibility of a popup menu only to a certain Project Type?
body: <p>I am using menuContributions+popup to show a context menu in my plugin.xml. I need to limit it's visibility only to</p>
  
  <ol>
  <li>certain type of Project(e.g. Dynamic Web Project) (Menu should appear on right click of only parent project folder) and</li>
  <li>a particular folder(e.g Web Content) and it's sub folders inside the Project Folder structure.</li>
  </ol>
  
  <p>I was able to achieve the 1) condition to some extent by using</p>
  
  <pre><code>&lt;menuContribution locationURI="popup:common.new.menu?after=additions"&gt;
              &lt;command
                  label="Web Wiz"
                  commandId="commandId"
                  icon="icons/sample.gif"&gt;
                 &lt;visibleWhen&gt;
                    &lt;with  variable="selection"&gt;
                              &lt;iterate ifEmpty="false"
                          operator="or"&gt;
                       &lt;instanceof
                             value="org.eclipse.core.resources.IProject"/&gt;
                    &lt;/iterate&gt;
                    &lt;/with&gt;
                 &lt;/visibleWhen&gt;
              &lt;/command&gt;
          &lt;/menuContribution&gt;
  </code></pre>
  
  <p>but it appears for all kinds of projects...I need to limit it to only a <strong>Dynamic Web Project</strong>, so what should I add to meet this requirement in plugin.xml?</p>