java - Android ListView not showing but the data from json is there -

the problem list not showing, network connection fine. tried running app several times. 1/10 runs, list there , can see data database. don't know problem i'm using volley data

package com.example.wackyroad.internannouncement;   public class mainactivity extends listactivity {  private static final string get_url = "http://xxx"; private static final string tag_id = "id"; private static final string tag_title = "title"; private static final string tag_content = "content"; private static final string tag_date = "date"; private arraylist<hashmap<string, string>> listarraylist = new arraylist<hashmap<string, string>>(); private progressdialog pdialog; private listadapter adapter;  @override protected void oncreate(bundle savedinstancestate) {     super.oncreate(savedinstancestate);     setcontentview(r.layout.activity_main);      getannouncement();     updatelist();  }  @override public boolean oncreateoptionsmenu(menu menu) {     // inflate menu; adds items action bar if present.     getmenuinflater().inflate(r.menu.menu_main, menu);     return true; }  @override public boolean onoptionsitemselected(menuitem item) {     // handle action bar item clicks here. action bar     // automatically handle clicks on home/up button, long     // specify parent activity in androidmanifest.xml.     int id = item.getitemid();      //noinspection simplifiableifstatement     if (id == r.id.refresh) {         return true;     }      return super.onoptionsitemselected(item); }   private void getannouncement() {     stringrequest postrequest = new stringrequest(request.method.post, get_url,             new response.listener<string>() {                 @override                 public void onresponse(string response) {                      try {                         jsonobject jsonresponse = new jsonobject(response);                          try {                             jsonarray data = jsonresponse.getjsonarray("announcements");                              (int = 0; < data.length(); i++) {                                 jsonobject c = data.getjsonobject(i);                                  hashmap<string, string> map = new hashmap<string, string>();                                 map.put(tag_id, c.getstring("announcement_id"));                                 map.put(tag_title,  c.getstring("announcement_title"));                                 map.put(tag_content, c.getstring("announcement_content"));                                 map.put(tag_date, c.getstring("announcement_date"));                                 listarraylist.add(map);                             }                          } catch (exception e) {                             e.printstacktrace();                          }                     } catch (exception e) {                         e.printstacktrace();                     }                     pdialog.dismiss();                 }             },             new response.errorlistener() {                 @override                 public void onerrorresponse(volleyerror error) {                     error.printstacktrace();                     pdialog.dismiss();                 }             }      ) {     };      pdialog = new progressdialog(mainactivity.this);     pdialog.setmessage("getting announcements..");     pdialog.show();      volley.newrequestqueue(getapplication()).add(postrequest);  }  private void updatelist() {      adapter = new simpleadapter(this, listarraylist,             r.layout.activity_lv_list, new string[]{tag_id, tag_title, tag_content,             tag_date}, new int[]{r.id.tv_id, r.id.tv_title, r.id.tv_content, r.id.tv_date});       setlistadapter(adapter);      listview lv = getlistview();     lv.setonitemclicklistener(new adapterview.onitemclicklistener() {          @override         public void onitemclick(adapterview<?> parent, view view,                                 int position, long id) {             string tv_id = ((textview) view.findviewbyid(r.id.tv_id)).gettext().tostring();             intent = new intent(getapplicationcontext(), announcement_details.class);             i.putextra("id", tv_id);             startactivity(i);          }     }); }   } 

i tried logging jsonresponse , data fetched. here's jsondata

02-08 10:34:38.676    6258-6258/com.example.wackyroad.internannouncement d/jsonresponse﹕ {"announcements":[{"announcement_title":"sample title here","announcement_content":"sample content","announcement_id":"1","announcement_date":"2016-02-04"},{"announcement_title":"sample title","announcement_content":"sample content again","announcement_id":"2","announcement_date":"2016-02-04"},{"announcement_title":"it's not working","announcement_content":"i don't know","announcement_id":"3","announcement_date":"2016-02-08"}],"message":"post available!","success":1} 

i think problem in population of data in listview

getannouncement() asynchronous operation. have call updatelist() method after request completed.