How to add editable text box to a custom annotation?

Hi,

I have been trying to create a custom annotation and have been successful in that front. However, I am stuck now. I want to add an editable text box to my custom annotation and I am at a loss at how to do so. The editable text box is to be used by the user as an input text box.

Please guide or provide some sample on this. I am on an urgent deadline. Quick help will be appreciated.

Thanks!