android - Andriod Listview fast scroll to bottom automatically when scroll in the middle -

i have listview fastscroll enabled , functioning properly, issue when scroll in middle scroll bar automatically comes bottom , not stick particular position. have idea please share.

following main code list adapter:

    public class contactadapter extends arrayadapter<user> implements filterable, sectionindexer {         private static string sections = "";    // rest variable declaration      public contactadapter(context context, list<user> users,fragmentmanager fragmentmanager,string section) {             super(context, r.layout.contact_row, new distinctmodelslist<>(users));             this.users = users;              this.sections=section;             this.layoutinflater = ((activity)context).getlayoutinflater();             filter = new contactsfilter();             this.fragmentmanager=fragmentmanager;         }      // rest view function , static modal class declaration        @override         public int getpositionforsection(int section) {             log.d("listview", "get position section");             (int i=0; < this.getcount(); i++) {                 try {                     string item = this.getitem(i).getdisplayname().touppercase();                     if (item.charat(0) == sections.charat(section))                         return i;                 }catch (exception e){                  }             }             return 0;         }          @override         public int getsectionforposition(int arg0) {             log.d("listview", "get section");              return 0;         }          @override         public object[] getsections() {             string[] sectionsarr = new string[sections.length()];             (int i=0; < sections.length(); i++)                 sectionsarr[i] = "" + sections.charat(i);             return sectionsarr;         }     }