android - Launching Activity from Fragment -

i have activity single fragment asks user login. once person logs in, new activity launched. question is, once the person enters credentials , hits login button on fragment should

a)the fragment alert current activity first , there start new activity. example, here fragment:

public class loginfragment extends fragment implements view.onclicklistener { private button loginbutton; private clickedinterface clickedinterface;  public loginfragment() {     // required empty public constructor }  static interface clickedinterface{     public void buttonclicked(view v); }  @override public view oncreateview(layoutinflater inflater, viewgroup container,                          bundle savedinstancestate) {     view view = inflater.inflate(r.layout.fragment_login, container, false);     loginbutton = (button)view.findviewbyid(r.id.fragment_login_loginbutton);     loginbutton.setonclicklistener(this);     return view; }  @override public void onattach(activity activity) {     super.onattach(activity);     this.clickedinterface = (clickedinterface)activity; }  @override public void ondetach() {     super.ondetach();     clickedinterface = null; }  @override public void onclick(view v) {     switch (v.getid()){         case r.id.fragment_login_loginbutton:{             clickedinterface.buttonclicked(v);             break;         }     } } 

and here activity using clickedinterface method:

    @override public void buttonclicked(view v) {     switch (v.getid()){         case r.id.fragment_login_loginbutton:{             //do stuff             break;         }     } } 

or

b)launch new activity right fragment?

thank you

it totally depends on business logic have in fragment, , whether you're using in multiple activities. example, might have share button, , button sends intent rate app in play store.

in sharing scenario, might want each activity have different share text. in case, reference of activity, check implements interface, delegate activity:

// share scenario (delegate activity)  if (getactivity() instanceof mycallback) {     ((mycallback)getactivity()).launchmyintent(); // todo handle callback in activity } 

however, if know fact want 1 behaviour regardless of in app (like rating button), might make sense send intent straight fragment.

// rating scenario (send intent fragment  getactivity().startactivity(myintent);