"Connected" even when wifi is off

Question

Mission is to check if the mobile is connected on internet or not. I have problem. It shows "Connected" even when wifi is off. Here is my class.

public class InterneProvjera {
    Context context;
    @SuppressLint("MissingPermission")
    public InterneProvjera(Context context){
        this.context = context;
    }

    public boolean isNetworkAvailable() {
        ConnectivityManager connectivity = (ConnectivityManager) this.context.getSystemService(Context.CONNECTIVITY_SERVICE);
        if (connectivity != null) {
            NetworkInfo[] info = connectivity.getAllNetworkInfo();
            if (info != null) {
                for (NetworkInfo i: info) {
                    if (i.getState() == NetworkInfo.State.CONNECTED)
                        return true;
                }
            }
        }
        return false;
    }
}

And here is in the main activity :

InterneProvjera interneProvjera = new InterneProvjera(this);
        String tKonekcija = (interneProvjera.isNetworkAvailable()) ?  "Connected" : "No connection";
        txtIspis.setText(tKonekcija);

Sorry if its trivial question im new in android programming. Ps: is there any Connection listener and how to check internet signal strength (3G, 4G, wifi)?

Answer 1

You should use BroadcastReceiver to check the network status using ConnectivityManager

Below is the code to check in your activity if network is connected or not. If connected, it will show you name of network in Toast:

ConnectivityStatusReceiver.java

public class ConnectivityStatusReceiver extends BroadcastReceiver {

  @Override
  public void onReceive(Context context, Intent intent) {

    final ConnectivityManager connMgr = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);

    NetworkInfo activeNetworkInfo = connMgr.getActiveNetworkInfo();

    if (activeNetworkInfo != null) {
      Toast.makeText(context, activeNetworkInfo.getTypeName() + " connected", Toast.LENGTH_SHORT).show();
    } else {
      Toast.makeText(context, "No Internet or Network connection available", Toast.LENGTH_LONG).show();
    }
  }

}

MainActivity.java

public class MainActivity extends AppCompatActivity {
  ConnectivityStatusReceiver connectivityStatusReceiver;

  @Override
  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    connectivityStatusReceiver = new ConnectivityStatusReceiver();
  }

  @Override
  protected void onResume() {
    super.onResume();
    IntentFilter intentFilter = new IntentFilter(ConnectivityManager.CONNECTIVITY_ACTION);
    registerReceiver(connectivityStatusReceiver, intentFilter);
  }

  @Override
  protected void onDestroy() {
    super.onDestroy();
    if (connectivityStatusReceiver != null) {
      // unregister receiver
      unregisterReceiver(connectivityStatusReceiver);
    }
  }
}