android - How access dial pad during the call? -

i working on conference manager application .i using action_call function making call , action_dial dialing number.but call going separate , dial action separate.can me?here code

private void call(int profileid) {

    profiledo profile = adapter.getprofile(profileid);      int stepcount = 0;     long previousstepdelay = 0;     (stepdo step : profile.getsteps()) {         intent callintent;          string url = "tel:" + step.getvalue();         stepcount++;         if (stepcount == 1) {              callintent = new intent(intent.action_call, uri.parse(url));             startactivity(callintent);          } else {             try {                 thread.sleep(previousstepdelay * 1000);                 system.out.println("hai");              } catch (interruptedexception e) {                 e.printstacktrace();             }              callintent = new intent(intent.action_dial, uri.parse(url));              startactivity(callintent);          }         previousstepdelay = step.getdelay();      } } 

}