How to use evt_text_enter?

evt_text_enter(id) { | event | … }

I read above line in wxruby doc, if I’m not mistaken
it catch enter key pressed while editing a textbox
I tried to use it but it doesnot work

my code looks like this

evt_text_enter(@textbox.get_id) {|e| do_something(e)}

def do_something(e)
puts @textbox.get_value
end

how is the right way to use that event?