Object variable or With block variable not set

I am receiving this Message "Object variable or With block variable not set" I really would like to get over it. Please take a look on the piece of code.

 For i As Integer = 0 To textObjects.Count - 1
                    'Set the name of Column in TextObject.
                    textObjects(i).Text = String.Empty
                    If sdr.FieldCount > i Then
                        textObjects(i).Text = sdr.GetName(i)
                    End If
                Next

                'Load all the data rows in the Dataset.

THERE I GOT THE MESSAGE IN THE PIECE BELOW:
                While sdr.Read()
                    Dim dr As DataRow = dsLangues.Tables(0).Rows.Add()
                    For i As Integer = 0 To sdr.FieldCount - 1
                        dr(i) = sdr(i)
                    Next
                End While