ADG - How to suppress some folders?

Question

I have an XML data tree I'm displaying. Some leaf nodes have child data that is used to drive a column display attribute. I don't necessarily want that data to be viewed with a folder icon.
That might be enough info. But I can't help be more verbose. Think of a debugger. A tree of structs. Each struct has member data. We have a snapshot of this member data over time and a slider to scrub through it. The leaf node has an array of data that we wish to drive it's value. But we don't want to see that as a folder.
for example:
struct Foo
     int var;
Foo foo;
foo.var = 1;
foo.var = 2;
on frame 1 would display as
(+) foo Foo
  |-  var   int   1
not
(+) foo Foo
  (+)  var   int   1
    |- 1
    |- 2
I have a custom item renderer for the value field that is driven by the array. That works fine. But I can't suppress the folder icon ( and expandability ).
Ideas?

Answer 1

What you're trying to do is deceptively simple. Just remove the columns from the group.
For example, the MXML for your
(+) Foo
     (+) foo
          |- var 1
structure would look something like this:
<mx:GroupingField name="Foo">
     <mx:summaries>
          <mx:SummaryRow summaryPlacement="group">
               <mx:fields>
                    <mx:SummaryField label="Foo" dataField="Foo" operation="SUM"/>
                    <mx:SummaryField label="var1" dataField="var1" operation="SUM"/>
               </mx:fields>
          </mx:SummaryRow>
     </mx:summaries>
</mx:GroupingField> 
<mx:columns>
     <mx:AdvancedDataGridColumn headerText="Foo" dataField="Foo" width="100"/>
     <mx:AdvancedDataGridColumn headerText="var" dataField="var1" width="100"/>
</mx:columns>
To get rid of it, simply do this to your mx:columns array:
<mx:columns>
      <mx:AdvancedDataGridColumn headerText="var" dataField="var1"  width="100"/>
</mx:columns>