Android - Google Fit - Get user's speed -

i'm building app needs user's current speed using google fit's android api. api finds datatype.type_speed without problem, using finddatasources method, speed value never gets returned. code follows:

private void buildfitnessclient() {     mclient = new googleapiclient.builder(this)             .addapi(fitness.sensors_api)             .addscope(new scope(scopes.fitness_location_read))             .addconnectioncallbacks(new googleapiclient.connectioncallbacks() {                 @override                 public void onconnected(bundle bundle) {                     showtoast("connected");                     //calls fitness api                       fitness.sensorsapi.finddatasources(mclient, new datasourcesrequest.builder()                             // @ least 1 datatype must specified.                             .setdatatypes(datatype.type_speed)                             .build())                             .setresultcallback(new resultcallback<datasourcesresult>() {                                 @override                                 public void onresult(datasourcesresult datasourcesresult) {                                     string text = "";                                     (datasource datasource : datasourcesresult.getdatasources()) {                                         text += "data source type: " + datasource.getdatatype().getname() + "\n";                                          if(datasource.getdatatype().equals(datatype.type_speed) && mlistener == null) {                                             showtoast("mlistener");                                             registerfitnessdatalistener(datasource, datatype.type_speed);                                         }                                     }                                      tvaveragespeed.settext(text);                                 }                             });                 }                  @override                 public void onconnectionsuspended(int i) {                     if(i == googleapiclient.connectioncallbacks.cause_network_lost)                         showtoast("connection lost. cause: network lost");                     else if(i == googleapiclient.connectioncallbacks.cause_service_disconnected)                         showtoast("connection lost. cause: service disconnected");                 }             })             .addonconnectionfailedlistener(new googleapiclient.onconnectionfailedlistener() {                 @override                 public void onconnectionfailed(connectionresult connectionresult) {                     log.d(tag, "connection failed. reason: " + connectionresult);                      if(!connectionresult.hasresolution()) {                         //show localized error dialog                         googleplayservicesutil.geterrordialog(connectionresult.geterrorcode(),                                 mainactivity.this, 0).show();                         return;                     }                      if(!authinprogress) {                         try {                             log.d(tag, "attempting resolve failed connection");                             authinprogress = true;                             connectionresult.startresolutionforresult(mainactivity.this,                                     request_oauth);                         }catch(intentsender.sendintentexception e) {                             showtoast("exception while starting resolution activity");                         }                     }                 }             }).build(); }  private void registerfitnessdatalistener(datasource datasource, datatype datatype) {     mlistener = new ondatapointlistener() {         @override         public void ondatapoint(datapoint datapoint) {             for(field field : datapoint.getdatatype().getfields()) {                 value val = datapoint.getvalue(field);                 showtoast("val");                 tvaveragespeed.settext(val.tostring());             }         }     };      fitness.sensorsapi.add(             mclient,             new sensorrequest.builder()                     .setdatasource(datasource)                     .setdatatype(datatype)                     .setsamplingrate(10, timeunit.seconds)                     .build(),             mlistener)             .setresultcallback(new resultcallback<status>() {                                    @override                                    public void onresult(status status) {                                        if(status.issuccess()) {                                            showtoast("speed listener registered");                                        }else{                                            showtoast("problem while registering listener");                                        }                                    }                                }             ); } 

what doing wrong? thank you

i not of here, setadd after .setdatatypes

.setdatasourcetypes(datasource.type_derived) 

and make sure got permissions right

.addapi(fitness.sensors_api) .addscope(new scope(scopes.fitness_location_read)) 

when creating api client object. in either case speed not common data source, instead use distance , divide time accordingly.