web services - Convert android AsyncTask call to a separate class and call from all activities -

i new android development. have asynctask function in application. calling http request activities. in each activity using following class connect server, in activities called twice !!.

basically web developer , in such cases use single class can accessed entire application(web) , use common function same activity. difference input , out put changed.

my doubt in case can use ( convert) such function or class ? assume

1. create android class ( can accessed activities )
2. just make json string need specific server ( process in server )
3. just pass created json created class , made http connect )
4. process returned data server
5. pass corresponding activity

so can use same function activities , can avoid duplicate query

can convert code such manner ?

my code

public class mainactivity extends activity {         @override     protected void oncreate(bundle savedinstancestate) {         super.oncreate(savedinstancestate);         setrequestedorientation (activityinfo.screen_orientation_portrait);         setcontentview(r.layout.activity_main);                  login loginuser = new login();         loginuser.execute("");   }           private class login extends asynctask<string, integer, string> {           @override         protected string doinbackground(string... surl) {             try {           string path = "http://www.domain_name.com/app/checksession.php";          httpclient client = new defaulthttpclient();         httpconnectionparams.setconnectiontimeout(client.getparams(), 10000);                   httpresponse response;                 jsonobject json = new jsonobject();                 try {                     httppost post = new httppost(path);                     json.put("access_token", "123456");                       post.setheader("json", json.tostring());                     stringentity se = new stringentity(json.tostring());                     se.setcontentencoding((header) new basicheader(http.content_type, "application/json"));                     post.setentity(se);                response = client.execute(post);                     /* checking response */                     if (response != null) {                         inputstream in = response.getentity().getcontent();                           string = convertstreamtostring(in);                          jsonobject jsono = stringtojsonobj(a);                         string passedstringvalue = jsono.getstring("result");                          if(passedstringvalue.equals("1")){                             flags=1;                             //log.v("tagg", "success");                         }                         else {                             flags=0;                             //log.v("tagg", "failed !");                         }                     }                 } catch (exception e) {                     e.printstacktrace();                 }                     } catch (exception e) {             }             return null;         }          @override         protected void onpreexecute() {               super.onpreexecute();             showdialogue("login processing", "loading");         }          @override         protected void onprogressupdate(integer... progress) {             super.onprogressupdate(progress);         }          @override         protected void onpostexecute(string result) {             if(flags.equals(1)){             itent homepage = new intent(mainactivity.this, registerdevice.class);             startactivity(homepage);             finish();             }             else {                 intent homepage = new intent(mainactivity.this, loginactivity.class);                 startactivity(homepage);                 finish();             }             super.onpostexecute(result);         }      }  } 

please 1 help/advise in advance

extract class different file , make public

    public class login extends asynctask<object, integer, string> {         private iloginlistener listener;          @override         protected string doinbackground(object... arg0) {             try {                this.listener = (iloginlistener) arg0[0];               //you can send url in obj array               string theurl = (string) arg0[1];           string path = "http://www.domain_name.com/app/checksession.php";          httpclient client = new defaulthttpclient();         httpconnectionparams.setconnectiontimeout(client.getparams(), 10000);                   httpresponse response;                 jsonobject json = new jsonobject();                 try {                     httppost post = new httppost(path);                     json.put("access_token", "123456");                       post.setheader("json", json.tostring());                     stringentity se = new stringentity(json.tostring());                     se.setcontentencoding((header) new basicheader(http.content_type, "application/json"));                     post.setentity(se);                response = client.execute(post);                     /* checking response */                     if (response != null) {                         inputstream in = response.getentity().getcontent();                           string = convertstreamtostring(in);                          jsonobject jsono = stringtojsonobj(a);                         string passedstringvalue = jsono.getstring("result");                          if(passedstringvalue.equals("1")){                             flags=1;                             //log.v("tagg", "success");                         }                         else {                             flags=0;                             //log.v("tagg", "failed !");                         }                     }                 } catch (exception e) {                     e.printstacktrace();                 }                     } catch (exception e) {             }             return null;         }          @override         protected void onpreexecute() {               super.onpreexecute();             showdialogue("login processing", "loading");         }          @override         protected void onprogressupdate(integer... progress) {             super.onprogressupdate(progress);         }          @override         protected void onpostexecute(string result) {             listener.loginsessionchecklistener(flag.equals(1));             super.onpostexecute(result);         }      } 

regarding other question, have interface that, this:

    public interface iloginlistener {          public void loginsessionchecklistener(someneeded value);       } 

i implement interface in class need postexecute result , in overriden method can want result of task. class user this:

public class someclass implements iloginlistener {       //call class:      login logintask = new login();      object[] someparams = new object[2];      //add listener     someparams[0] = someclass.this     //add url      someparams[1] = someurlstring;      logintask.execute(someparams);     @override    public void loginsessionchecklistener(someneeded value){     //do stuff results     } }