java - Callback in android(Network call in separate class) -

i have layout xml name main.xml , have main.java class in class send network call , data rest service.but want separate network call in anohther class.how can that.

main.xml

<linearlayout xmlns:android="http://schemas.android.com/apk/res/android"     xmlns:tools="http://schemas.android.com/tools"     android:layout_width="match_parent"     android:layout_height="match_parent"     android:orientation="vertical"     tools:context=".mainactivity" >      <textview         android:layout_width="wrap_content"         android:layout_height="wrap_content"         android:text="@string/hello_world" />     <button         android:id="@+id/callsubclass"         android:layout_width="match_parent"         android:layout_height="wrap_content"         android:text="call sub-class" />     <textview         android:id="@+id/result"         android:layout_width="match_parent"         android:layout_height="wrap_content" />  </linearlayout> 

main.java

 protected void oncreate(bundle savedinstancestate) {         super.oncreate(savedinstancestate);         setcontentview(r.layout.activity_main);         buttoncallsubclass = (button)findviewbyid(r.id.callsubclass);         textresult = (textview)findviewbyid(r.id.result);         // can set network call here , update textview         textresult .settext(result);     } 

rest service response ={"id":1958,"content":"hello, world!"}

my separate nework.java class

string url1 = string.format("http://rest-service.guides.spring.io/greeting");         jsonobjectrequest jsonobjreq = new jsonobjectrequest(request.method.get,                 url1, null,                 new response.listener<jsonobject>() {                      @override                     public void onresponse(jsonobject response) {                         log.d("test", response.tostring());                         string token="a";                         string id="";                         string result="";                         try {                             id= response.get("id").tostring();                             result= response.get("content").tostring();                         }catch (jsonexception e){                             e.printstacktrace();                             toast.maketext(getapplicationcontext(),                                     "error: " + e.getmessage(),                                     toast.length_long).show();                         }                       } 

now want network call in separate class give solution.