java - How call method from second activitty and return value -

i have 2 activity, first on activity "loginactivity",and second activity "student_ activity". please till me how call method "call" second activity , return value bool first activity know user if id , password correct or not correct. first activity id , password "edittext" send id , password method in second activity sure data server.

code first activity :

    public class loginactivity extends activity{         edittext edtid;         edittext edtpassword;         button btn1;         sharedpreferences prefs;           @override             public void oncreate(bundle savedinstancestate) {                 super.oncreate(savedinstancestate);                 setcontentview(r.layout.login);                  prefs = this.getsharedpreferences(this.getapplicationcontext().getpackagename(), context.mode_private);                 edtid=(edittext)findviewbyid(r.id.idstudent);                 edtpassword=(edittext)findviewbyid(r.id.passwordstudent);                  btn1=(button)findviewbyid(r.id.btnlogin);                   btn1.setonclicklistener(new onclicklistener() {                     @override                     public void onclick(view v) {                         createloginsession(integer.parseint(edtid.gettext().tostring()),edtpassword.gettext().tostring()); //here call second activity sure data                           intent intent = new intent(loginactivity.this,tofi.android.student_activity.class);                             startactivity(intent);                                   finish();                         startactivity(new intent(loginactivity.this,com.jcxavier.widget.test.badgebuttontestactivity.class));                     }                 });                }     //this method store data in sharedpreferences data in second activity           public void createloginsession(int id, string password){              sharedpreferences.editor editor = prefs.edit();              editor.putint("id", id);              editor.putstring("password", password);              editor.commit();             }     } 

code second activity is:

   public class student_activity { sharedpreferences prefs = this.getsharedpreferences(this.getapplicationcontext().getpackagename(), context.mode_private);      public void oncreate(bundle icicle) {                 super.oncreate(icicle);                 setcontentview(r.layout.program_student);                 newsloader call = new newsloader();     call.execute(this, true);                    }                private context context;             private boolean pullfromserver = false;             class newsloader extends asynctask<object, void, list<student>> {                 private context context;                 private boolean pullfromserver = false;                  protected list<student> doinbackground(object... params) {                     context = (context) params[0];                     pullfromserver = (boolean) params[1];                     datasource.open();                     if (pullfromserver) {     //get attribute sharedpreferences                           int id = prefs.getint("id", 24);                         string password = prefs.getstring("password","wce");     // studenthandler class sure password content method call send server , //return value if correct or not correct , return value type bool.                         bool s;                         s = studenthandler.getinstance().call(context,id,password);         }          }      } 

1. call startactivityforresult() (documentation) , override onactivityresult() (documentation) in first activity.

2. in second activity perform whatever validation need (this done in first activity passing data via intent) , call setresult(int resultcode, intent data) (documentation) , finish(); second activity.

if using startactivityforresult() not feasible situation, can use setresult() , startactivity(), pass data need via intent, , validate in onactivityresult().

i skimmed on this, here's example of in action.