android - Copy file with hook -

i'm working ionic application , need replace mainactivity generated, new 1 create. since use ibm mfp analytics plugin , other tests.

the hook creates:

#!/bin/bash gulp build 

in hook folder have:

hooks ---- before_build      ----            mainactivity.java           all_before_build.sh 

lo que necesito es agregar este hook la linea

cp mainactivity.java platforms/android/src/cl/my_app/android/ 

however, when execute hook error:

cp: cannot stat 'mainactivity.java': no such file or directory 

i know error not find file mainactivity.java, if is, explained above directory.

edit

the previous problem solved, leaving full path of mainactivity.java, when run application, works fine opens notepad code.