can i glue on a bit that is stopping my phone turn on?

I have a very old nokia 3310c and it just died on me. I changed the battery for my girlfriends fully charged battery and the phone is dead . I have tried to charge it by the socket plug but nothing. when I looked on internet I saw a diagram of the on /off switch problem . mine looks very similar , the tiny little bit has broken of so I was wondering if I could glue it back will it still work ??? please help !!!1