Issue in frgment replace in FragmentStatePagerAdapter tabhoast matireal design android -

i want integrate tabhoast material design android write below code

public class activitypaymentmodule extends appcompatactivity implements materialtablistener {  private viewpager pager; private materialtabhost tabhost; private viewpageradapter pageradapter; private resources res; public static int tabposition = 0;  private allmethods allmethods;  private string titles[]={"tab1","tab2, "tab3","tab4"};  @override protected void oncreate(bundle savedinstancestate) {     super.oncreate(savedinstancestate);     setcontentview(r.layout.activity_payment_module);     res = this.getresources();      allmethods = new allmethods(activitypaymentmodule.this);      toolbar toolbar = (toolbar) this.findviewbyid(r.id.toolbar);     toolbar.settitletextcolor(color.white);     toolbar.settitle("demo");     this.setsupportactionbar(toolbar);      initcontrols();     setpageradapter(); }  private void initcontrols() {     tabhost = (materialtabhost)findviewbyid(r.id.materialtabhost);      pager = (viewpager) this.findviewbyid(r.id.pager);      pageradapter =  new viewpageradapter(getsupportfragmentmanager()); }  private void setpageradapter() {     pager.setadapter(pageradapter);     tabhost.setaccentcolor(color.white);     pager.setonpagechangelistener(new viewpager.simpleonpagechangelistener() {         @override         public void onpageselected(int position) {             // when user swipe selected tab change             tabposition = position;             tabhost.setselectednavigationitem(position);         }     });      (int = 0; < pageradapter.getcount(); i++) {         tabhost.addtab(                 tabhost.newtab()                         .settext(titles[i])                         .settablistener(this)         );     } }  @override public void ontabselected(materialtab materialtab) {     pager.setcurrentitem(materialtab.getposition()); }  @override public void ontabreselected(materialtab materialtab) { }  @override public void ontabunselected(materialtab materialtab) {  }  private class viewpageradapter extends fragmentstatepageradapter {     public viewpageradapter(fragmentmanager fm) {         super(fm);     }     @override     public fragment getitem(int position) {           if (position == 0) {             return new fragment1();         }else if (position == 1) {             return new fragment2();         }else if(position == 2){             return new fragment3();         }          else {             return new fragment4();         }     }     @override     public int getcount() {         return 4;     }     @override     public charsequence getpagetitle(int position) {         return titles[position];     } }  @override public boolean oncreateoptionsmenu(menu menu) {     // inflate menu; adds items action bar if present.     getmenuinflater().inflate(r.menu.income_menu, menu);     menu.finditem(r.id.action_dasbboard).setvisible(false);     menu.finditem(r.id.action_feedback).setvisible(false);     return true; } @override public boolean onoptionsitemselected(menuitem item) {     switch (item.getitemid()) {         // respond action bar's up/home button         case r.id.terms:              intent browserintent2 = new intent(intent.action_view, uri.parse("http://worldofrental.com/terms-of-service/"));             startactivity(browserintent2);             return true;         case r.id.policy:              intent browserintent3 = new intent(intent.action_view, uri.parse("http://worldofrental.com/privacy-policy/"));             startactivity(browserintent3);         case r.id.action_dasbboard:              return true;          case r.id.action_help:              intent browserintent = new intent(intent.action_view, uri.parse("http://worldofrental.com/help-center/"));             startactivity(browserintent);             return true;      }     return super.onoptionsitemselected(item); }  @override public void onbackpressed() {     super.onbackpressed();     this.finish(); } 

}

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i face 2 issues: (1) when first time load screen @ time fragment1() , fragment2() both called. (2)when swipe fragment @ time fragment replace position not maintain when swipe fragment1() right left @ time fragment3() , fragment2() both called

when run above code @ first time fragment1() , fragment2() both fragment called. , when swipe fragment position not maintain replacing idea how can solve ? suggestions appreciable.