plugins/org.eclipse.gmf.codegen.xtend.ui/plugin.xml

<?xml version="1.0" encoding="UTF-8"?>
<?eclipse version="3.4"?>
<plugin>
  <extension point="org.eclipse.ui.menus">
    <menuContribution locationURI="popup:org.eclipse.jdt.ui.PackageExplorer">
        <command
            commandId="org.eclipse.gmf.codegen.xtend.ui.handler.GenerationCommand"
            style="push">
            <visibleWhen
                  checkEnabled="false">
                  <iterate>
       <adapt type="org.eclipse.core.resources.IResource">
          <test property="org.eclipse.core.resources.name" 
                value="*.gmfgen"/>
       </adapt>
    </iterate>
            </visibleWhen>
        </command>
    </menuContribution>
    </extension>
    
   <extension
         point="org.eclipse.ui.popupMenus">
      <objectContribution
            adaptable="true"
            id="gmf.codegen.xtend.ui.executeTemplatesWithXtend2"
            nameFilter="*.gmfgen"
            objectClass="org.eclipse.core.resources.IFile">
         <action
               label="Generate Diagram Code (Xtend2)"
               class="org.eclipse.gmf.codegen.xtend.ui.handlers.ExecuteTemplatesActionWithXtend2"
               menubarPath="additions"
               enablesFor="1"
               id="gmf.codegen.xtend.ui.executeTemplatesActionWithXtend2">
         </action>
      </objectContribution>
    </extension>
    
</plugin>