TinyMCE and rails

I am a rails n00b. I want to use tinyMCE instead of a textarea that got created automatically via scaffolding. so Im using tinyMCE hammer. the scaffolding automatically created this line

<%= f.text_area :descripcion %>

and I substituted it with

<%= tinymce(:descripcion) %>

When I load the view it looks just fine but when I try to submit the descripcion field of my model object is null.开发者_JS百科... help please

You need to keep the f. if you're in a form_for block:

<%= f.tinymce :descripcion %>