Here you can find all states of call, just make handle this states, like i did:
public class PhoneState extends PhoneStateListener {
@Override
public void onCallStateChanged(int state, String incomingNumber) {
switch (state) {
case TelephonyManager.CALL_STATE_IDLE:
//Some Action
break;
case TelephonyManager.CALL_STATE_OFFHOOK:
break;
case TelephonyManager.CALL_STATE_RINGING:
//Some Action
break;
//case TelephonyManager.ANOTHER_STATE: ...
}
}
}