只要連接更改 ，您就必須使用Brodcast Receiver註冊列表程序，然後像這樣檢查互聯網連接。
public class NetworkConnectivityListener {
\t private static final String TAG = "NetworkConnectivityListener";
\t private static final boolean DBG = true;
\t private Context mContext;
\t private State mState;
\t private boolean mListening;
\t private String mReason;
\t private boolean mIsFailover;
\t boolean isWifiConnected = false;
\t boolean isMobileConnected = false;
\t private static NetworkConnectivityListener Networkobject;
\t private MainThreadBus mThreadBus;
\t public static NetworkConnectivityListener newInstance() {
\t \t if (Networkobject == null) {
\t \t \t Networkobject = new NetworkConnectivityListener();
\t \t }
\t \t return Networkobject;
\t }
\t /** Network connectivity information */
\t private NetworkInfo mNetworkInfo;
\t /**
\t * In case of a Disconnect, the connectivity manager may have already
\t * established, or may be attempting to establish, connectivity with another
\t * network. If so, {@code mOtherNetworkInfo} will be non-null.
\t */
\t private NetworkInfo mOtherNetworkInfo;
\t private ConnectivityBroadcastReceiver mReceiver;
\t private class ConnectivityBroadcastReceiver extends BroadcastReceiver {
\t \t @SuppressWarnings("deprecation")
\t \t @Override
\t \t public void onReceive(Context context, Intent intent) {
\t \t \t String action = intent.getAction();
\t \t \t if (!action.equals(ConnectivityManager.CONNECTIVITY_ACTION)
\t \t \t \t \t || mListening == false) {
\t \t \t \t Log.d(TAG, "onReceived() called with " + mState.toString()
\t \t \t \t \t \t + " and " + intent);
\t \t \t \t return;
\t \t \t }
\t \t \t ConnectivityManager connMgr = (ConnectivityManager) context
\t \t \t \t \t .getSystemService(Context.CONNECTIVITY_SERVICE);
\t \t \t NetworkInfo networkInfo = connMgr
\t \t \t \t \t .getNetworkInfo(ConnectivityManager.TYPE_WIFI);
\t \t \t if (networkInfo != null)
\t \t \t \t isWifiConnected = networkInfo.isConnected();
\t \t \t networkInfo = connMgr
\t \t \t \t \t .getNetworkInfo(ConnectivityManager.TYPE_MOBILE);
\t \t \t if (networkInfo != null)
\t \t \t \t isMobileConnected = networkInfo.isConnected();
\t \t \t Log.d("network status", "wifi == " + isWifiConnected
\t \t \t \t \t + " and mobile == " + isMobileConnected);
\t \t \t boolean noConnectivity = intent.getBooleanExtra(
\t \t \t \t \t ConnectivityManager.EXTRA_NO_CONNECTIVITY, false);
\t \t \t if (noConnectivity) {
\t \t \t \t mState = State.NOT_CONNECTED;
\t \t \t } else {
\t \t \t \t mState = State.CONNECTED;
\t \t \t }
\t \t \t mNetworkInfo = (NetworkInfo) intent
\t \t \t \t \t .getParcelableExtra(ConnectivityManager.EXTRA_NETWORK_INFO);
\t \t \t mOtherNetworkInfo = (NetworkInfo) intent
\t \t \t \t \t .getParcelableExtra(ConnectivityManager.EXTRA_OTHER_NETWORK_INFO);
\t \t \t mReason = intent.getStringExtra(ConnectivityManager.EXTRA_REASON);
\t \t \t mIsFailover = intent.getBooleanExtra(
\t \t \t \t \t ConnectivityManager.EXTRA_IS_FAILOVER, false);
\t \t \t System.out.println("Printing the MYTest" + mNetworkInfo);
\t \t \t if (DBG) {
\t \t \t \t Log.d(TAG,
\t \t \t \t \t \t "onReceive(): mNetworkInfo="
\t \t \t \t \t \t \t \t + mNetworkInfo
\t \t \t \t \t \t \t \t + " mOtherNetworkInfo = "
\t \t \t \t \t \t \t \t + (mOtherNetworkInfo == null ? "[none]"
\t \t \t \t \t \t \t \t \t \t : mOtherNetworkInfo + " noConn="
\t \t \t \t \t \t \t \t \t \t \t \t + noConnectivity) + " mState="
\t \t \t \t \t \t \t \t + mState.toString());
\t \t \t }
\t \t \t mThreadBus.post(getState());
\t \t }
\t };
\t public enum State {
\t \t UNKNOWN,
\t \t /** This state is returned if there is connectivity to any network **/
\t \t CONNECTED,
\t \t /**
\t \t * This state is returned if there is no connectivity to any network.
\t \t * This is set to true under two circumstances:
\t \t * <ul>
\t \t * <li>When connectivity is lost to one network, and there is no other
\t \t * available network to attempt to switch to.</li>
\t \t * <li>When connectivity is lost to one network, and the attempt to
\t \t * switch to another network fails.</li>
\t \t */
\t \t NOT_CONNECTED
\t }
\t /**
\t * Create a new NetworkConnectivityListener.
\t */
\t public NetworkConnectivityListener() {
\t \t mState = State.UNKNOWN;
\t \t mReceiver = new ConnectivityBroadcastReceiver();
\t }
\t /**
\t * This method starts listening for network connectivity state changes.
\t *
\t * @param context
\t */
\t public synchronized void startListening(Context context,Bus bus) {
\t \t if (!mListening) {
\t \t \t mContext = context;
\t \t \t mThreadBus=new MainThreadBus(bus);
\t \t \t IntentFilter filter = new IntentFilter();
\t \t \t filter.addAction(ConnectivityManager.CONNECTIVITY_ACTION);
\t \t \t context.registerReceiver(mReceiver, filter);
\t \t \t mListening = true;
\t \t }
\t }
\t /**
\t * This method stops this class from listening for network changes.
\t */
\t public synchronized void stopListening() {
\t \t if (mListening) {
\t \t \t mContext.unregisterReceiver(mReceiver);
\t \t \t mContext = null;
\t \t \t mNetworkInfo = null;
\t \t \t mOtherNetworkInfo = null;
\t \t \t mIsFailover = false;
\t \t \t mReason = null;
\t \t \t mThreadBus=null;
\t \t \t mListening = false;
\t \t }
\t }
\t public State getState() {
\t \t return mState;
\t }
\t /**
\t * Return the NetworkInfo associated with the most recent connectivity
\t * event.
\t *
\t * @return {@code NetworkInfo} for the network that had the most recent
\t * connectivity event.
\t */
\t public NetworkInfo getNetworkInfo() {
\t \t return mNetworkInfo;
\t }
\t /**
\t * If the most recent connectivity event was a DISCONNECT, return any
\t * information supplied in the broadcast about an alternate network that
\t * might be available. If this returns a non-null value, then another
\t * broadcast should follow shortly indicating whether connection to the
\t * other network succeeded.
\t *
\t * @return NetworkInfo
\t */
\t public NetworkInfo getOtherNetworkInfo() {
\t \t return mOtherNetworkInfo;
\t }
\t /**
\t * Returns true if the most recent event was for an attempt to switch over
\t * to a new network following loss of connectivity on another network.
\t *
\t * @return {@code true} if this was a failover attempt, {@code false}
\t * otherwise.
\t */
\t public boolean isFailover() {
\t \t return mIsFailover;
\t }
\t /**
\t * An optional reason for the connectivity state change may have been
\t * supplied. This returns it.
\t *
\t * @return the reason for the state change, if available, or {@code null}
\t * otherwise.
\t */
\t public String getReason() {
\t \t return mReason;
\t }
\t public boolean iswifiConnected() {
\t \t return isWifiConnected;
\t }
\t public boolean ismobileConnected() {
\t \t return isMobileConnected;
\t }
\t public class MainThreadBus extends Bus {
\t \t private final Bus mBus;
\t \t private final Handler mHandler = new Handler(Looper.getMainLooper());
\t \t public MainThreadBus(final Bus bus) {
\t \t \t if (bus == null) {
\t \t \t \t throw new NullPointerException("bus must not be null");
\t \t \t }
\t \t \t mBus = bus;
\t \t }
\t \t @Override
\t \t public void post(final Object event) {
\t \t \t System.out.println("Printing the Value of Send" + event);
\t \t \t if (Looper.myLooper() == Looper.getMainLooper()) {
\t \t \t \t mBus.post(event);
\t \t \t } else {
\t \t \t \t mHandler.post(new Runnable() {
\t \t \t \t \t @Override
\t \t \t \t \t public void run() {
\t \t \t \t \t \t mBus.post(event);
\t \t \t \t \t }
\t \t \t \t });
\t \t \t }
\t \t }
\t }
}
我在這裏使用otto，但您可以使用偵聽器。