Suppose you’re reporting test scores, grouped by age. You display the number of tests scored in an Text component in the group’s footerBand. The text of the Text component is an expression codeblock that calls the agCount( ) method:

{||this.parent.parent.agCount({||this.parent.rowset.fields[ "Score" ].value})}

To get to the Group object’s agCount( ) method from a component in the footerBand,

this is the component.

The component’s parent is the footerBand.

The footerBand’s parent is the Group.

The expression codeblock that is passed to agCount( ) also uses dot operators:

this is the Group object that performs the calculation.

The Group object’s parent is the StreamSource.

The StreamSource object contains the rowset.