java - Service losing bind (mBoundService = null) -

i've got working version fragment pasing json string main activity has tcp socket service bound it:

main_activity:

...   private serviceconnection mconnection = new serviceconnection() {         @override         public void onserviceconnected(componentname name, ibinder service) {             mboundservice = ((socket_service.localbinder) service).getservice();         }          @override         public void onservicedisconnected(componentname name) {             mboundservice = null;             log.d("tcp client: main_activity", "onservicedisconnected called!");         }     };      ...         public void writebyte(string jsonobject) {             if (mboundservice != null) {                 mboundservice.sendmessage(jsonobject);             }         }     ... 

fragment:

... main_activity activity = (main_activity) getactivity();         activity.writebyte(jsonobject.tostring());  ... 

---------------------------------------------------------------------------------------------

i'd create separate class (no fragment) create json string, pass main_activity passes service. did that, it's not working, because mboundservice gets value "null" , cant pass service anymore.

fragment:

json pwmjason = new json();         pwmjason.cratepwmjson(pwm1,pwm2,pwm3,pwm4,pwm5,pwm6,pwm7); 

json.class:

package de.l.led.control.background;  import android.app.fragment; import android.util.log;  import org.json.jsonarray; import org.json.jsonexception; import org.json.jsonobject;  import de.l.led.control.main_activity;   public class json extends main_activity{      public void cratepwmjson(int pwm1, int pwm2, int pwm3, int pwm4, int pwm5, int pwm6, int pwm7){         jsonobject jsonobject = new jsonobject();         jsonarray jsonarray = new jsonarray();          try {             //jsonarray.put("");             jsonarray.put(pwm1 * 64);             jsonarray.put(pwm2 * 64);             jsonarray.put(pwm3 * 64);             jsonarray.put(pwm4 * 64);             jsonarray.put(pwm5 * 64);             jsonarray.put(pwm6 * 64);             jsonarray.put(pwm7 * 64);             jsonobject.put("pwms", jsonarray);          } catch (jsonexception e) {             e.printstacktrace();         }         log.d("jso", "received json string: " + jsonobject.tostring());         main_activity activity = new main_activity();         activity.writebyte(jsonobject.tostring());     }  } 

any ideas?

thanks

i propose use this:

public class jsonhelper{      public static string cratepwmjson(int pwm1, int pwm2, int pwm3, int pwm4, int pwm5, int pwm6, int pwm7){         jsonobject jsonobject = new jsonobject();         jsonarray jsonarray = new jsonarray();          try {             //jsonarray.put("");             jsonarray.put(pwm1 * 64);             jsonarray.put(pwm2 * 64);             jsonarray.put(pwm3 * 64);             jsonarray.put(pwm4 * 64);             jsonarray.put(pwm5 * 64);             jsonarray.put(pwm6 * 64);             jsonarray.put(pwm7 * 64);             jsonobject.put("pwms", jsonarray);          } catch (jsonexception e) {             e.printstacktrace();         }         log.d("jso", "received json string: " + jsonobject.tostring());         return jsonobject.tostring();     } } 

then in fragment can call like:

string pwmjsonasstring = jsonhelper().cratepwmjson(pwm1,pwm2,pwm3,pwm4,pwm5,pwm6,pwm7); main_activity activity = (main_activity) getactivity(); activity.writebyte(pwmjsonasstring);