Unless I'm mistaken NetTalk can't do this (if I am please tell me) so I decided to hack a solution. I put the following code
Access:InvoiceTransaction.Insert()
InsertResult:IsInvalid = TRUE
ItemCode:IsInvalid = TRUE
!loc:alert = 'Item Added'
loc:InvalidTab = 0
loc:Invalid = 'ITR:LocationID'
ItemCode = ''
InsertResult = 'Item added. Add another?'
ITR:Quantity = 1
ITR:Price = 0
ITR:Cost = 0
ITR:Notes = ''
p_web.ssv('ItemCode', ItemCode)
p_web.ssv('InsertResult', InsertResult)
p_web.ssv('ITR:Quantity', ITR:Quantity)
p_web.ssv('ITR:Price', ITR:Price)
p_web.ssv('ITR:Cost', ITR:Cost)
p_web.ssv('ITR:Notes', ITR:Notes)
do Refresh::ItemCode
It works fine except the reset field values don't show up in the forum. Except for [InsertResult] which is a display field.