判断wifi或者3g是否打开的方法

 public boolean goodNet() {
  ConnectivityManager manager = (ConnectivityManager) getSystemService(CONNECTIVITY_SERVICE);
  NetworkInfo networkinfo = manager.getActiveNetworkInfo();
  if (networkinfo == null || !networkinfo.isAvailable()) {

   return false;
  }

  return true;
 }

如果返回true说明3g或者wifi已经连接，反之返回false

 

 private void checkNetworkInfo() {//判断使用的是那种网络
  ConnectivityManager conMan = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE); // mobile
                           // 3G
                           // Data
                           // Network
  State mobile = conMan.getNetworkInfo(ConnectivityManager.TYPE_MOBILE)
    .getState();

  State wifi = conMan.getNetworkInfo(ConnectivityManager.TYPE_WIFI)
    .getState();

 }