Unfortunately, <project name> has stopped

Question

I want Android get Wifi Router Name. MainActivity.java has this code. But When I run I get the following error Unfortunately, has stopped. Thanks

WifiManager wifiMgr = (WifiManager) getActivity().getSystemService(Context.WIFI_SERVICE);
WifiInfo wifiInfo = wifiMgr.getConnectionInfo();
String WifiName = wifiInfo.getSSID();

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

    TextView outputWifiName = (TextView) findViewById(R.id.sysInf);

    outputWifiName.setText(WifiName);

}

private Activity getActivity() {
    // TODO Auto-generated method stub
    return null;
}

Answer 1

Your getActivity returns null you should initialize wifiMgr inside onCreate

WifiManager wifiMgr =null;
WifiInfo wifiInfo = null;
String WifiName = null;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    setContentView(R.layout.activity_main);
     wifiMgr= (WifiManager) this.getSystemService(Context.WIFI_SERVICE);
     wifiInfo = wifiMgr.getConnectionInfo();
    WifiName = wifiInfo.getSSID();
    TextView outputWifiName = (TextView) findViewById(R.id.sysInf);

    outputWifiName.setText(WifiName);

}