android - addOnScrollListener, pass base and limit -

i learning how use onscrolllistner

the recyclerokhttphandler class execute select base 0 , limit 5 server. want execute again recyclerokhttphandler new data , examle base 5 limit 10. when adding below on onscrolllistner

       handler.execute().get(); 

i got error :

cannot execute task: task has been executed (a task can executed once) 

ok understand cannot execute again task , how should passe base , limit ?

this (it working) execute class images server, need pass base 0 , limit 5

   final recyclerokhttphandler handler = new recyclerokhttphandler( this, new recyclerokhttphandler.myinterface() {         @override         public void mymethod(arraylist result) {             madapter_first = new myadapter(result,searchactivity.this);             madapter_first.notifydatasetchanged();             mrecyclerview_first.setadapter(madapter_first);         }     },"girls",base,limit);      try {          handler.execute().get();      } catch (exception e) {        log.d("searchactivity error", "error in mrecyclerview_first");          e.printstacktrace();     } 

and addonscrolllistener,

 mrecyclerview_first.addonscrolllistener(new recyclerview.onscrolllistener() {          @override         public void onscrolled(recyclerview recyclerview, int dx, int dy) {             super.onscrolled(recyclerview, dx, dy);              visibleitemcount = mrecyclerview_first.getchildcount();             totalitemcount = mlayoutmanager.getitemcount();             firstvisibleitem = mlayoutmanager.findfirstvisibleitemposition();              if (loading) {                 if (totalitemcount > previoustotal) {                     loading = false;                     previoustotal = totalitemcount;                     system.out.println("previoustotal:" + previoustotal);                     system.out.println("totalitemcount:" + totalitemcount);                     system.out.println("visibleitemcount:" + visibleitemcount);                  }             }             if (!loading && (totalitemcount - visibleitemcount)                     <= (firstvisibleitem + visiblethreshold)) {                 // end has been reached                 system.out.println(totalitemcount);                  log.i("yaeye!", "end called");          //       base =string.valueof(firstvisibleitem);        //         limit=string.valueof(visibleitemcount);                  //                 try {                     handler.execute().get();                  } catch (exception e) {                     log.d("searchactivity error", "error in mrecyclerview_first");                      e.printstacktrace();                 }                 loading = true;             }         }     }); 

this class recyclerokhttphandler

public class recyclerokhttphandler extends asynctask<string, void, string> {     private context mcontext;     private myinterface mlistener;     public string category;     public string basestart;     public string limitend;     public recyclerokhttphandler(context context, myinterface mlistener, string categ, string base, string limit){         mcontext = context;         this.mlistener  = mlistener;         category=categ;         basestart=base;         limitend=limit;     }     public interface myinterface {         public void mymethod(arraylist result);     }      private final string fetch_url = "http://justedhak.com/old-files/recyclerview_data.php";     // arraylist<listitem> listitem;     arraylist<categorylist> listitem;     int resulta;      okhttpclient httpclient = new okhttpclient();     listview list;     string myjson;     jsonarray peoples = null;     inputstream inputstream = null;      @override     protected string doinbackground(string... params) {         log.d("okhttp fetch_url", fetch_url);            requestbody formbody = new formencodingbuilder()                 .add("category", category)                 .add("base", basestart)                 .add("limit", limitend)                 .build();         request request = new request.builder()                 .url(fetch_url)                 .post(formbody)                 .build();           string result = null;         try {             response response = httpclient.newcall(request).execute();             if (!response.issuccessful()) throw new ioexception("unexpected code " + response);             inputstream = response.body().bytestream();             bufferedreader reader = new bufferedreader(new inputstreamreader(inputstream, "utf-8"), 8);             stringbuilder sb = new stringbuilder();             string line = null;             while ((line = reader.readline()) != null)             {                 sb.append(line + "\n");             }             result = sb.tostring();             resulta = 1; //"success             //  return response.body().bytes();         } catch (exception e) {             toast.maketext(mcontext, "connection failed, check connection",                     toast.length_long).show();             e.printstacktrace();        }         {             try{if(inputstream != null)inputstream.close();}catch(exception squish){}         }         return result;     }     @override     protected void onpostexecute(string result){         if( resulta ==1){             myjson=result;             log.e("result",result);              showlist();         }         else{             log.e("d","there error on postexecute in okhhttphandler.java");          }     }      protected void showlist(){         try {              jsonobject jsonobj = new jsonobject(myjson);             peoples = jsonobj.getjsonarray("result");             system.out.println("length:"+peoples.length());             int j_length=peoples.length()-1;             //jsonobject maxj  = peoples.getjsonobject(peoples.length() - 1);             // max of arrray              jsonobj= peoples.getjsonobject(j_length);              string j_id=  jsonobj.getstring("id");             int _id = integer.parseint(j_id);             system.out.println(j_id);              //max of             databasehandler db = new databasehandler(mcontext);             string db_id="";             db_id = db.getmax();             if (db_id== null)             {                 db_id="0";             }             int d_id = integer.parseint(db_id);             log.e("db_id", db_id);             log.e("j_id",j_id);              //  if (_id < d_id) {             system.out.println("getting json result ");              listitem = new arraylist<categorylist>();             (int = 0; < peoples.length(); i++) {                 jsonobject c = peoples.getjsonobject(i);                  string id = c.getstring("id");                 string url = c.getstring("url");                    listitem.add(new categorylist(id, url));             }              if (mlistener != null)                 mlistener.mymethod(listitem);           } catch (jsonexception e) {             e.printstacktrace();         }     }      } 

i read problem again, , solution might create new recyclerokhttphandler each time. that's error message says , that's how asynctasks work. if call .execute() once cannot call again, have create new object.

still should override onpostexecute() else blocking ui thread. have @ asynctask. need code recyclerokhttphandler more...