Android判断网络连接状态

• 需要相关权限

<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>
<uses-permission android:name="android.permission.ACCESS_WIFI_STATE"/>
<uses-permission android:name="android.permission.INTERNET"/>

• 在界面中，存在一个按钮，单击按钮的情况下，判断当前的网络连接状态，分别在连接网络状态和未连接网络状态下，提示相关信息。代码如下：

public class MainActivity extends Activity {

private Button button;//对应的按钮
    private ConnectivityManager connetivityManager;//
    private NotificationManager notificationManager;// 通知用户网络状况
    private BroadcastReceiver broadcastReceiver = new BroadcastReceiver() {

@Override
        public void onReceive(Context contex, Intent intent) {
            // TODO Auto-generated method stub
            // 网络状况
            NetworkInfo mobileInfo = connetivityManager
                    .getNetworkInfo(ConnectivityManager.TYPE_MOBILE);
            NetworkInfo wifiInfo = connetivityManager
                    .getNetworkInfo(ConnectivityManager.TYPE_WIFI);

Notification.Builder builder = new Notification.Builder(
                    MainActivity.this);
            builder.setContentTitle("提示信息");
            builder.setSmallIcon(R.drawable.ic_launcher);
            if (!mobileInfo.isConnected() && !wifiInfo.isConnected()) {
                builder.setContentText("网络状态有异常");
            } else {
                builder.setContentText("网络正常");
            }
            notificationManager.notify(1001, builder.build());
        }
    };

@Override
    protected void onCreate(Bundle savedInstanceState) {
        // TODO Auto-generated method stub
        super.onCreate(savedInstanceState);
        setContentView(R.layout.mainactivity);
        button = (Button) findViewById(R.id.button1);
        button.setOnClickListener(new OnClickListener() {

@Override
            public void onClick(View arg0) {
                // TODO Auto-generated method stub
                IntentFilter intentFilter = new IntentFilter();
                intentFilter.addAction(ConnectivityManager.CONNECTIVITY_ACTION);
                registerReceiver(broadcastReceiver, intentFilter);
                connetivityManager = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);
                notificationManager = (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);
            }
        });
    }

// 卸载广播
    @Override
    protected void onPause() {
        // TODO Auto-generated method stub
        super.onPause();
        if (broadcastReceiver != null) {
            unregisterReceiver(broadcastReceiver);
        }
    }
}