- public static boolean isNetworkAvailable(Context context) {
- ConnectivityManager connectivity = (ConnectivityManager)context.getSystemService(Context.CONNECTIVITY_SERVICE);
- if (connectivity == null) {
- Log.i("NetWorkState", "Unavailabel");
- return false;
- } else {
- NetworkInfo[] info = connectivity.getAllNetworkInfo();
- if (info != null) {
- for (int i = 0; i < info.length; i++) {
- if (info[i].getState() == NetworkInfo.State.CONNECTED) {
- Log.i("NetWorkState", "Availabel");
- return true;
- }
- }
- }
- }
- return false;
- }
上面这个方法就是判断网络是否连接的代码，返回true表示有网络，返回false表示无网络。 在Android网络应用程序开发中，经常要判断网络连接是否可用，因此经常有必要监听网络状态的变化。android的网络状态监听可以用 BroadcastReceiver来接收网络状态改变的广 播，具体实现如下：
- @Override
- public void onReceive(Context context, Intent intent) {
- Log.e(TAG, "网络状态改变");
- boolean success = false;
- //获得网络连接服务
- ConnectivityManager connManager = (ConnectivityManager) getSystemService(CONNECTIVITY_SERVICE);
- // State state = connManager.getActiveNetworkInfo().getState();
- State state = connManager.getNetworkInfo(
- ConnectivityManager.TYPE_WIFI).getState(); // 获取网络连接状态
- if (State.CONNECTED == state) { // 判断是否正在使用WIFI网络
- success = true;
- }
- state = connManager.getNetworkInfo(
- ConnectivityManager.TYPE_MOBILE).getState(); // 获取网络连接状态
- if (State.CONNECTED != state) { // 判断是否正在使用GPRS网络
- success = true;
- }
- if (!success) {
- Toast.makeText(LocationMapActivity.this, "您的网络连接已中断", Toast.LENGTH_LONG).show();
- }
- }
在Activity的onCreate中:
- //注册网络监听
- IntentFilter filter = new IntentFilter();
- filter.addAction(ConnectivityManager.CONNECTIVITY_ACTION);
- registerReceiver(mNetworkStateReceiver, filter);
- //在Activity中的onDestroy中:‘
- unregisterReceiver(mNetworkStateReceiver); //取消监听