How to expose a .net Table Adapter's Data Adapter

I have a AVB.NET project working with SQL  Server 2005 that includes a DataSet with Table Adapters and Binding Sources for several tables.  I'd like to expose the Table Adapter's underlying DataAdapter so that I can monitor the progress of table fill operations using a Progress bar.  A portion of the auto-generated code shows:
Partial Public Class vw_MI_RequisitionTableAdapter
        Inherits Global.System.ComponentModel.Component
       
        Private WithEvents _adapter As Global.System.Data.SqlClient.SqlDataAdapter
       
        Private _connection As Global.System.Data.SqlClient.SqlConnection
       
        Private _commandCollection() As Global.System.Data.SqlClient.SqlCommand
       
        Private _clearBeforeFill As Boolean

and I have tried to add a Partial Class as follows:
Public ReadOnly Property DataAdapter() As System.Data.SqlClient.SqlDataAdapter
            Get
                'Here we return the private member of the tableadapter
                Return _adapter
            End Get
        End Property
    End Class
But the reference to _adapter is marked with the dreaded squiggly underline saying that it isn't declared.

What am I missing here.  And from a broader viewpoint, is there a better eay to tie a Progress Bar to a data table Fill?

Thanks