добавьте открытый метод в MainActivity, к которому можно обратиться из вашего второго класса:
public class MainActivity extends AppCompatActivity {
TextView tv;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
tv=(TextView)findViewById(R.id.info);
}
public void onSubmit(View v) {
TelephonyManager tm=(TelephonyManager)getSystemService(Context.TELEPHONY_SERVICE);
tm.listen(new SecondActivity(this),PhoneStateListener.LISTEN_SIGNAL_STRENGTHS);
String opname="\nOperator ID:"+" "+tm.getNetworkOperator();
opname=opname+"\nOperator Name:"+" "+tm.getNetworkOperatorName();
int phoneType=tm.getPhoneType();
String ptype="";
switch(phoneType)
{
case TelephonyManager.PHONE_TYPE_CDMA:
ptype="\nPhone Type: CDMA\n";
break;
case TelephonyManager.PHONE_TYPE_GSM:
ptype="\nPhone Type: GSM\n";
break;
case TelephonyManager.PHONE_TYPE_SIP:
ptype="\nPhone Type: SIP\n";
break;
case TelephonyManager.PHONE_TYPE_NONE:
ptype="\nPhone Type: NONE\n";
break;
}
tv.setText(opname+ptype);
}
//declare a public method which is accessable in onSignalStrengthsChanged callback in the second class.
public void do_what_you_wanna_do_with_these_two_values(double value1,double value2){
tv.setText("here are my values: "+String.valueOf(value1)+" , "+String.valueOf(value1));
}
}
и используйте его для передачи информации в MainActivity:
public class SecondActivity extends PhoneStateListener {
Context mcontext;
double value1=0,value2=0;
String error,ss;
private MainActivity first_activity_instance;
public SecondActivity(Context context){
mcontext=context;
first_activity_instance =(MainActivity)mcontext;
}
public void onSignalStrengthsChanged(SignalStrength signalStrength){
super.onSignalStrengthsChanged(signalStrength);
if (signalStrength.isGsm()) {
value1=signalStrength.getGsmBitErrorRate();
error="\nGsmBitErrorRate:"+value1;
value2=signalStrength.getGsmSignalStrength();
ss="\nGsmSignalStrength:"+value2;
//now pass them to your to your activity instance
first_activity_instance.do_what_you_wanna_do_with_these_two_values(value1,value2);
}
}
}