android - Facebook SDK4.0 Login using custom view -

i want log in user inside app using new facebook sdk custom view. here fragment's oncreateview():

@override public view oncreateview(layoutinflater inflater, viewgroup container,                          bundle savedinstancestate) {     mview = inflater.inflate(r.layout.fragment_login, container, false);      linearlayout facebook = (linearlayout) mview.findviewbyid(r.id.facebook_button);     facebook.setonclicklistener(new facebookloginlistener());      loginmanager.getinstance().registercallback(mcontext.mfacebookcallbackmanager,             new facebookcallback<loginresult>() {                 @override                 public void onsuccess(loginresult loginresult) {                     // app code                     log.d("resultado", "success");                 }                  @override                 public void oncancel() {                     // app code                     log.d("resultado", "cancel");                 }                  @override                 public void onerror(facebookexception exception) {                     // app code                     log.d("resultado", exception.tostring());                 }              });      return mview;  }  @override public void onattach(activity activity) {     mcontext = (mainactivity) activity;     super.onattach(activity); }    public class facebookloginlistener implements view.onclicklistener {     @override     public void onclick(view view) {         loginmanager.getinstance().loginwithreadpermissions(                 loginfragment.this,                 arrays.aslist("email"));      } } 

and on mainactivity

@override protected void oncreate(bundle savedinstancestate) {     facebooksdk.sdkinitialize(getapplicationcontext());     setcontentview(r.layout.activity_main);     mfacebookcallbackmanager = callbackmanager.factory.create(); }  @override protected void onactivityresult(int requestcode, int resultcode, intent data) {     super.onactivityresult(requestcode, resultcode, data);     mfacebookcallbackmanager.onactivityresult(requestcode, resultcode, data); } 

the facebook login activity shows i'm not getting callback... correct way implement login?