Android 網絡狀態變化的監聽

1.在流量網頁，時實現斷網，提醒等功能。

　需要權限

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

2.注冊一個BroadcastReceiver來接受網絡狀態的變化

public class NetworkChange extends BroadcastReceiver {
    @Override
    public void onReceive(Context context, Intent intent) {
        ConnectivityManager connectivityManager= (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
        NetworkInfo networkInfo=connectivityManager.getNetworkInfo(ConnectivityManager.TYPE_MOBILE);
        NetworkInfo wifiinfo=connectivityManager.getNetworkInfo(ConnectivityManager.TYPE_WIFI);
        if(!networkInfo.isConnected()&&!wifiinfo.isConnected()){

            /**
             *
             */
            Toast.makeText(context,"網絡不可用!",Toast.LENGTH_SHORT).show();

        }else{
            if(wifiinfo.isConnected()){
                Toast.makeText(context,"wifi連接中!",Toast.LENGTH_SHORT).show();

            }
            if(networkInfo.isConnected()){
                Toast.makeText(context,"流量連接中!",Toast.LENGTH_SHORT).show();

            }
        }

    }
}

3.在activity總注冊接收器即可：

public class MainActivity extends AppCompatActivity {

   private IntentFilter intentFilter;
    private NetworkChange networkChange;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        /**
         * 監聽網絡狀態
         */
        intentFilter=new IntentFilter();
        intentFilter.addAction("android.net.conn.CONNECTIVITY_CHANGE");
        networkChange=new NetworkChange();
        registerReceiver(networkChange,intentFilter);
     
    }

 /**
     * 動態注冊接受者，記得取消注冊
     */
    @Override
    protected void onDestroy() {
        super.onDestroy();
        unregisterReceiver(networkChange);
    }
}