android - Switching between activities along with fragments -

i have functionality below.

start activity -> in oncreate(), display fragment1

in activity 1, fragment1, using getactivity() method activity instance.

activity1

//replace fragment replacelistfragment(new fragment1(), r.id.fragment_main_layout_container); 

here fragment1 code.

    public void onactivitycreated(bundle savedinstancestate) {         super.onactivitycreated(savedinstancestate);         activity = (activity1) getactivity();     } 

navigate activity b -> in oncreate(), display fragment2

activity2

//replace fragment replacelistfragment(new fragment2(), r.id.fragment_main_layout_container); 

here fragment2 code.

    public void onactivitycreated(bundle savedinstancestate) {         super.onactivitycreated(savedinstancestate);         activity = (activity2) getactivity();     } 

here button click code in fragment2

            finish();             intent intent = new intent(activity, activity1.class);             startactivity(intent); 

first navigation i.e., activity1 activity2 works fine. when moved activity2, in fragment2, have button, clicking on should redirect activity1. in oncreate() of activity1, placing fragment1, thought getactivity() of fragment1 should give activity1's instance. it's giving activity2's instance @ point.

thanks in advance.