Bug 139110 GUI enhancement to support create subquery more conveniently.
Description: GUI enhancement to support create subquery more conveniently. Steps to reproduce: Subquery means insert table/list inside another table/list item, and the inner table/list item doesn't has its own dataset binding. In latest build, if you want to creat a subquery structure, you have to use dataSetRow as binding expression for data items in inner table/list item. For example: 1. Insert a list, generate column data binding for it. 2. Add a group for the list. 3. Insert table to list group header which is used to display data rows in list group. Dont' bind table to dataset. 4. Insert a data to table detail row. 5. New a binding column for data, click to Open Expression Builder. The issue is that only "Availabel column bindings" is listed in Category but no "Available Data Sets". So I have to type dataSetRow[".."] by myself to generate correct subquery. For users, maybe they will mistakenly use "Available column bindings" which will generate expression like row._outer[".."] and get wrong result. So it is recommended to add "Available Data Sets" in Expression Builder for such case.
UI/org.eclipse.birt.report.designer.ui/src/org/eclipse/birt/report/designer/ui/dialogs/BindingExpressionProvider.java
return dataSeList;
		}
		if ( parent instanceof DataSetHandle )
		{
			return UIUtil.getColumnList( (DataSetHandle) parent );
		}
		return super.getChildrenList( parent );
	}
	public String getDisplayText( Object element )
	{
		if ( element instanceof DataSetHandle )
		{
			return ( (DataSetHandle) element ).getName( );
		}
		else if ( element instanceof ResultSetColumnHandle )
		{
			return ( (ResultSetColumnHandle) element ).getColumnName( );
		}
		return super.getDisplayText( element );
	}
	public String getInsertText( Object element )
	{
		if ( element instanceof ResultSetColumnHandle )
		{
			return DEUtil.getExpression( element );
		}
		return super.getInsertText( element );
	}
}