[news.eclipse.platform] Re: Contribute both a command Id plus an action

["Gary E. Barnes" <gebarnes@xxxxxxxxxx>]

Paul Webster wrote:
> Once you get this far, you would use org.eclipse.ui.handlers to 
> declaratively add a handler for the Navigator view.
>
> You would set the handler element activeWhen clause to something like:
> [xml]
> <activeWhen>
>   <with variable="activePartId">
>     <equals value="org.eclipse.ui.views.ResourceNavigator"/>
>   </with>
> </activeWhen>
> [/xml]
>
>
> When you are executed you'll be able to retrieve the navigator view in 
> your execute(*) method using:
> IWorkbenchPart part = HandlerUtil.getActivePart(event);

I'm using 3.2.  There doesn't appear to be a HandlerUtil in 3.2.  So I'm doing,

        Object  ac = event.getApplicationContext ();
        if (! (ac instanceof IEvaluationContext)) {
            return null;
        }
        IEvaluationContext context = (IEvaluationContext)ac;
         ... = context.getVariable ("activePart");

> You can also simply supply a default handler in your command definition 
> (but you can only supply one).

Does that work in 3.2?  It is documented in the 3.2 Help files but if I 
specify a default  handler it never gets invoked.  Never even gets constructed 
(I put a breakpoint in the constructor).

<command id="com.apex.ui.menu.compile.analyze"
	defaultHandler="com.action.TestHandler"
	name="%Button.analyze.name"
	description="%Button.analyze.tooltip"
	categoryId="com.ui.category.compile">
</command>

The org.eclipse.ui.handlers documention in 3.2 says "A handler that specifies 
no conditions is a default handler." But that doesn't work either.  If I do this,

<handler commandId="com.ui.menu.compile.analyze"
	class="com.action.TestHandler">
<!--
	<activeWhen>
	    <with variable="activePartId">
		<equals value="org.eclipse.ui.views.ResourceNavigator"/>
	    </with>
	</activeWhen>
-->
</handler>
With the activeWhen commented out the handler is never invoked.  With the 
activeWhen not commented out then the handler is invoked.

Is there perhaps a way to specify an activeWhen expression that is simply a 
constant TRUE literal?  Looking at the documentation there doesn't seem to be 
a way.

	Gary