android - Why isn't one of my tabs acting like the others? -

i'm still working on passing data between each fragment in tab navigation app. using callbacks set , value, didn't work properly. switched current method of calling methods in activity set , values, that's acting strange well.

when run app first fragment (first tab) gets value, , able change it. when swipe second tab, value not should be. when swipe third tab, value correct. value persistent on first , third tab (fragment), second tab doesn't want cooperate.

example:

• start - persistent_value = 0
• tab1 displayed - value shown 0
• change value on tab1 - persistent_value = 9
• swipe tab2 - value shown 0
• swipe tab3 - value shown 9
• change value on tab3 - persistent_value = 34
• swipe tab2 - value shown 0
• swipe tab1 - value shown 34

i'm not sure why second tab not updating, while both first , third are. doing wrong, or there i'm not aware of here?

here's example code i'm using try , solve problem.

public class mainactivity extends activity implements actionbar.tablistener {      sectionspageradapter msectionspageradapter;     viewpager mviewpager;      int persistent_value = 0;       public void setpersistentvalue(int value) {         this. persistent_value = value;     }      public int getpersistentvalue() {         return this.persistent_value;     }      @override     protected void oncreate(bundle savedinstancestate) {         super.oncreate(savedinstancestate);         setcontentview(r.layout.activity_main);          final actionbar actionbar = getactionbar();         actionbar.setnavigationmode(actionbar.navigation_mode_tabs);          msectionspageradapter = new sectionspageradapter(getfragmentmanager(), this);          mviewpager = (viewpager) findviewbyid(r.id.pager);         mviewpager.setadapter(msectionspageradapter);           mviewpager.setonpagechangelistener(new viewpager.simpleonpagechangelistener() {             @override             public void onpageselected(int position) {                 actionbar.setselectednavigationitem(position);             }         });           (int = 0; < msectionspageradapter.getcount(); i++) {             actionbar.addtab(                 actionbar.newtab()                     .settext(msectionspageradapter.getpagetitle(i))                     .settablistener(this));         }     }      @override     public void ontabselected(actionbar.tab tab, fragmenttransaction fragmenttransaction) {         mviewpager.setcurrentitem(tab.getposition());     }      public class sectionspageradapter extends fragmentpageradapter {          private context context;          public sectionspageradapter(fragmentmanager fm) {             super(fm);         }          public sectionspageradapter(fragmentmanager fm, context context) {             super(fm);             this.context = context;         }          @override         public int getcount() {             // show 3 total pages.             return 3;         }          @override         public charsequence getpagetitle(int position) {             locale l = locale.getdefault();             switch (position) {                 case 0:                     return getresources().getstring(r.string.tab_one_title);                 case 1:                     return getresources().getstring(r.string.tab_two_title);                 case 2:                     return getresources().getstring(r.string.tab_three_title);             }             return null;         }     }      public class mainfragment extends fragment {          private static final string arg_section_type = "section type";          int persistent_value;          public mainfragment(){}          public mainfragment(int sectionnumber) {             bundle args = new bundle();             args.putint(arg_section_type, sectionnumber);             setarguments(args);         }          @override         public view oncreateview(layoutinflater inflater, viewgroup container, bundle savedinstancestate) {             view rootview = inflater.inflate(r.layout.fragment_main, container, false);              persistent_value = ((mainactivity)getactivity()).getpersistentvalue;              textview textview = (textview) rootview.findviewbyid(r.id.the_value);             textview.settext(integer.tostring(this.persistent_value));              return rootview;         }          @override         public void onpause() {             super.onpause();             ((mainactivity)getactivity()).setpersistentvalue(this.persistent_value);         }          @override         public void onresume() {             super.onresume();             persistent_value = ((mainactivity)getactivity()).getpersistentvalue;              view rootview = getview();             textview textview = (textview) rootview.findviewbyid(r.id.the_value);             textview.settext(integer.tostring(this.persistent_value));         }     } } 

it seems in wrong way.

if need pass data between fragments, need use interface , not going pass data directly 1 fragment another, instead going pass activity first receiver fragment

please refer link fragment - fragment communication

http://developer.android.com/training/basics/fragments/communicating.html