android - Populating GridView from JSON using Async Task -

i trying populate grid view json received server. need populate gridview results obtained. below activity file populating grid view

public class opentableactivity extends activity {      string seruri, method;     opentableadapter op;      arraylist<hashmap<string, string>> tablelist = new arraylist<hashmap<string, string>>();      @override     protected void oncreate(bundle savedinstancestate) {         super.oncreate(savedinstancestate);         setcontentview(r.layout.open_table);          linearlayout layout = (linearlayout) findviewbyid(r.id.opentablelinear);         layout.setontouchlistener(new ontouchlistener() {             @override             public boolean ontouch(view view, motionevent ev) {                 hidekeyboard(view);                 return false;             }         });         gettables();             gridview gridview = (gridview) findviewbyid(r.id.grid);         gridview.setadapter(new opentableadapter(this));         button btn = (button) findviewbyid(r.id.table_home_btn);         btn.setonclicklistener(homebtn);     }      public boolean gettables() {          seruri = "tables.json";          method = "get";         webserviceasynctask webservicetask = new webserviceasynctask(opentableactivity.this);         webservicetask.execute(seruri, method, this);          return true;      }      public void writejsonarray(final jsonarray result, context contextinstance) {           try {              (int = 0; < result.length(); i++) {                 jsonobject c = result.getjsonobject(i);                   string tablabel = c.getstring("tablabel");                 string tabstatus = c.getstring("tabstatus");                  hashmap<string, string> map = new hashmap<string, string>();                   map.put("table_name", tablabel);                 map.put("table_status", tabstatus);                  tablelist.add(map);             }         } catch (jsonexception e) {             e.printstacktrace();         }      } 

below adapter class grid view

public class opentableadapter extends baseadapter {     private context mcontext;     string ordernumber;     opentableactivity openinstance;     string tablelabel;     string tablestatus;     //arraylist<hashmap<string, string>> tablist = null;      public opentableadapter(context c) {         // todo auto-generated constructor stub         mcontext = c;         //tablist = tablelist;     }       @override     public int getcount() {         // todo auto-generated method stub         openinstance = new opentableactivity();         return openinstance.tablelist.size();     }      @override     public object getitem(int arg0) {         // todo auto-generated method stub         return null;     }      @override     public long getitemid(int arg0) {         // todo auto-generated method stub         return 0;     }      @override     public view getview(int position, view convertview, viewgroup parent) {         view view = null;         if (convertview == null) {             layoutinflater li = (layoutinflater) mcontext                     .getsystemservice(context.layout_inflater_service);             view = li.inflate(r.layout.button, null);         } else {             view = convertview;         }         button btn = (button) view.findviewbyid(r.id.button);         openinstance = new opentableactivity();          (hashmap<string, string> map : openinstance.tablelist)             (java.util.map.entry<string, string> mapentry : map.entryset()) {                 string key = mapentry.getkey();                 string value = mapentry.getvalue();                 btn.settext(key); 

the tablelist populated correctly in writejsonarray. control goes adapter class gridview.setadapter(new opentableadapter(this));. executes nothing there. had put breakpoints see actual flow comes below method , nothing executed thereafter. there no error in trace , it's not executing anything.

public opentableadapter(context c) {     // todo auto-generated constructor stub     mcontext = c;  } 

i believe due incorrect context passed when comes async task 'post execute' method. tried passing context still same issue. please advise. thanks.

you have not initialized gridview

gridview gridview = (gridview) findviewbyid(r.id.gridview); 

you have edited post , have gridview initialized that's not problem.

initialize minflater in constructor of baseadapter class.also pass hashmap construcotr , use same in getview.

what doing in getview wrong openinstance = new opentableactivity() wrong. can start activity calling startactivity.

   layoutinflater minflater;      public opentableadapter(context c) {     mcontext = c;     minflater = layoutinflater.from(c);      tablist = tablelist;     } 

in getview

         viewholder holder;                if (convertview == null) {                   convertview = minflater.inflate(r.layout.button,                           parent, false);                  holder = new viewholder();                    holder.btn = (button) convertview.findviewbyid(r.id.button);                    convertview.settag(holder);              } else {                  holder = (viewholder) convertview.gettag();              }   // use tablelist data set text button using position index                         hashmap<string, string>> map = tablist.get(position)                  // use map set text button now.                      holder.btn.settext(key);             return convertview;      } 

use viewholder. http://developer.android.com/training/improving-layouts/smooth-scrolling.html

   static class viewholder    {      button btn;    }