[news.eclipse.platform.rcp] Synchronizing toggle state of Toolbar- and M

[vlr <robert.vogl@xxxxxx>]

Hi,

in my plugin.xml I have a certain command extension 
(org.eclipse.ui.commands) that is linked into two menuContributions: 
toolbar and menu (see below). Both menuContributions are of type 'toggle'.

How can I manage to keep the toggle state of these two items in sync 
(e.g. if the user toggles the state via the menu entry, the toolbar 
button must also change its state)?

Usually I would have expected such things should be done by the toolkit 
and not by the programmer...

Thanks in advance,

Excerpt from plugin.xml:
...
   <extension
         point="org.eclipse.core.expressions.definitions">
      <definition
            id="EditorIsOpen">
         <with
               variable="activeEditor">
            <instanceof
                  value="AbstractMyObjectEditor">
            </instanceof>
         </with>
      </definition>
   </extension>
   <extension
         point="org.eclipse.ui.commands">
      <command
            id="EnableMaskCommand"
            name="enable/disable Mask">
      </command>
   </extension>
   <extension
         point="org.eclipse.ui.menus">
      <menuContribution
            locationURI="toolbar:mainToolbar">
         <command
               commandId="EnableMaskCommand"
               icon="icons/edit.png"
               style="toggle">
            <visibleWhen
                  checkEnabled="true">
               <reference
                     definitionId="EditorIsOpen">
               </reference>
            </visibleWhen>
         </command>
      </menuContribution>
      <menuContribution
            locationURI="menu:edit">
         <command
               commandId="EnableMaskCommand"
               label="enable/disable Mask"
               style="toggle">
            <visibleWhen
                  checkEnabled="true">
               <reference
                     definitionId="EditorIsOpen">
               </reference>
            </visibleWhen>
         </command>
      </menuContribution>
   </extension>
   <extension
         point="org.eclipse.ui.handlers">
      <handler
            class="EnableMaskHandler"
            commandId="EnableMaskCommand">
      </handler>
   </extension>
...