java - Cannot resolve symbol (variables) -

i new android, great if me error "cannot resolve symbol ..." in variables:

- value 1

- banner_id

- full_id

my code following:

package com.example.sienstranslation.siensapp;  import android.content.intent; import android.net.uri; import android.support.v7.app.appcompatactivity; import android.os.bundle; import android.view.view; import android.widget.textview;  import com.android.volley.request; import com.android.volley.response; import com.android.volley.volleyerror; import com.android.volley.toolbox.stringrequest; import com.android.volley.toolbox.volley; import com.google.android.gms.appdatasearch.getrecentcontextcall;  import org.json.jsonexception; import org.json.jsonobject;  import java.util.hashmap; import java.util.map;  public class main3activity extends appcompatactivity {      @override     protected void oncreate(bundle savedinstancestate) {         super.oncreate(savedinstancestate);         setcontentview(r.layout.activity_main3);          intent intent=getintent();         double precio = intent.getextras().getdouble("precio");         string precio_rounded = string.format("%.2f", precio);         textview txtcambio = (textview) findviewbyid(r.id.textview4);         txtcambio.settext("precio total: "+ precio_rounded + " €");     }      void makepostrequest() {         string posting_url ="http://ipaddress/app.php";         // url path ok         stringrequest postrequest = new stringrequest(request.method.post, posting_url ,                 new response.listener<string>() {                     @override                     public void onresponse(string response) {                         try {                             jsonobject jsonresponse = new jsonobject(response);                             value1= jsonresponse.getstring("precio_rounded");                          } catch (jsonexception e) {                             e.printstacktrace();                             banner_id = null;                             full_id = null;                         }                     }                 },                 new response.errorlistener() {                     @override                     public void onerrorresponse(volleyerror error) {                         error.printstacktrace();                         value1= null;                     }                 }         ) {             // here params add url using post method             @override             protected map<string, string> getparams() {                 map<string, string> params = new hashmap<>();                 params.put("app", getstring(r.string.app_name));                 //params.put("2ndparamname","valueof2ndparam");                 return params;             }         };         volley.newrequestqueue(this).add(postrequest);     } 

thank time

at first , declare banner_id & full_id ;

public class main3activity extends appcompatactivity {  public int banner_id,full_id; 

then clean-rebuild project .