button

i create on form and on text field 'cmnt'

I want to add a comment with a data from a form field 'cmnt' , I can add an action to the form and write the next groovy code:

apiAccessor.getProcessAPI().addComment(rootProcessInstanceId, field_TextField1);

for that i done following . now in submit's button's > general tab > action > add action now there is two field

---- takes value of ----- now exactly where i have to write code ?

i tried by ---- takes value of -Code = give error Variable -- takes value of -- Code = give error

I am a new user of Bonita BPM version 6.2.3 Community edition. I have installed the application on Ubuntu Linux 32bit version 13.04 and 13.10. My Oracle Java version is 1.7.0_51.