i don't know about your question.. but check this out:
if t is a textbox, you are doing t = tf.InsertItemTemplate() and that could be an error.. don't you want to do the way around?? insert t into tf and then insert tf into the detailview????
Read this if you want to know how to get a correct reply for your question:
^^Took that from dparsons signature and he Took that from planoie's profile
My programs achieved a new certification (can you say the same?):
WORKS ON MY MACHINE