android - how change fragment textview with own java class? -

i tried change textview in activity of fragment in 3 cases, can't change textview.
there solution change textview of fragment in own fragment_activity or main_activity?

fragment.java

@override     public void oncreate(bundle savedinstancestate) {         super.oncreate(savedinstancestate);         if (getarguments() != null) {             mparam1 = getarguments().getstring(arg_param1);             mparam2 = getarguments().getstring(arg_param2);         }           textview textview = (textview) getview().findviewbyid(r.id.textview1);         textview.settext("done!");     }       @override     public view oncreateview(layoutinflater inflater, viewgroup container,                              bundle savedinstancestate) {         view view = inflater.inflate(r.layout.fragment_blank_fragment2, container, false);         textview tv = (textview) view.findviewbyid(r.id.textview1);         tv.settext("done!");         return view;     }      @override     public void onactivitycreated (bundle savedinstancestate) {         super.onactivitycreated(savedinstancestate);          textview tv = (textview) getview().findviewbyid(r.id.textview1);         tv.settext("done!");     } 

fragment.xml

...  <textview         android:textcolor="@color/myblack"         android:id="@+id/textview1"         android:layout_width="wrap_content"         android:layout_height="wrap_content"         android:text="test"         android:textappearance="?android:attr/textappearancemedium"         /> .... 

calling fragment class view in mainactivity:

@override     public void oncreate(bundle savedinstancestate) {         super.oncreate(savedinstancestate);         setcontentview(r.layout.main_weixin);          getwindow().setsoftinputmode(windowmanager.layoutparams.soft_input_state_always_hidden);         instance = this;  ...   view view2 = mli.inflate(r.layout.fragment_blank_fragment2, null);            views.add(view2); ... } 

thing know

1. in oncreate of fragment getview() returns null because still view in not created.
2. create method in fragment set value textview activity using fragment instance.

example : fragment

public class fragment1 extends fragment {       textview tv;     @override     public view oncreateview(layoutinflater inflater, viewgroup container, bundle savedinstancestate) {          view view = inflater.inflate(r.layout.fragment_blank_fragment2, container, false);         tv = (textview) view.findviewbyid(r.id.textview1);         tv.settext("done!");         return view;      }      public void setviewtext(string text){         tv.settext(text);     } } 

activity

public class myactivity extends fragmentactivity {      fragment1 fragment1;      @override     protected void oncreate(bundle arg0) {         super.oncreate(arg0);         setcontentview(r.layout.activity_fragment);         //as using static fragment create fragment instance using findfragmentbyid(id)         fragment1 = (fragment1) getsupportfragmentmanager().findfragmentbyid(r.id.fragment1);          fragment1.setviewtext("message");      } } 

visit official doc communicating other fragments
happy_coding :)