Question

我试图从CONNECTIVITY_ACTION接收BroadcastMessages：

    // register BroadcastReceiver on network state changes
    final IntentFilter mIFNetwork = new IntentFilter();
    mIFNetwork.addAction(android.net.ConnectivityManager.CONNECTIVITY_ACTION); //"android.net.conn.CONNECTIVITY_CHANGE"
    registerReceiver(mIRNetwork, mIFNetwork);

和接收者是：

private BroadcastReceiver mIRNetwork = new BroadcastReceiver() {
    @Override
    public void onReceive(final Context context, final Intent intent) {

        android.util.Log.i(TAG,"mIRNetwork: Network State Received: "+intent.getAction());
        Bundle extras = intent.getExtras();
        if (extras!=null){
                android.util.Log.i(TAG,"mIRNetwork: ACTION_BACKGROUND_DATA_SETTING_CHANGED: "+extras.getString(ConnectivityManager.ACTION_BACKGROUND_DATA_SETTING_CHANGED));
                android.util.Log.i(TAG,"mIRNetwork: CONNECTIVITY_ACTION: "+extras.getString(ConnectivityManager.CONNECTIVITY_ACTION));
                android.util.Log.i(TAG,"mIRNetwork: EXTRA_EXTRA_INFO: "+extras.getString(ConnectivityManager.EXTRA_EXTRA_INFO));
                android.util.Log.i(TAG,"mIRNetwork: EXTRA_NO_CONNECTIVITY: "+extras.getString(ConnectivityManager.EXTRA_NO_CONNECTIVITY));
                android.util.Log.i(TAG,"mIRNetwork: EXTRA_REASON: "+extras.getString(ConnectivityManager.EXTRA_REASON));

            }
        }

简而言之，总是空的。我认为，如果我松散WiFi连接，我应该得到EXTRA_NO_CONNECTIVITY（因为它是互联网的唯一途径）或至少从列表中的东西。但没有运气。如果我断开我的WiFi AP接收器获取他的消息，但有额外的空。当我再次打开我的WiFi接收器发射但没有额外的时候......为什么会这样？如何知道该应用程序丢失了任何网络连接？我想是这样的。

Answer 1

你不能得到额外的但你可以通过这种方式获得数据

private class ConnectivityBroadcastReceiver extends BroadcastReceiver {

    @Override
    public void onReceive(Context context, Intent intent) {
        boolean noConnectivity = intent.getBooleanExtra(ConnectivityManager
                .EXTRA_NO_CONNECTIVITY, false);
        NetworkInfo info1 = (NetworkInfo) intent.getParcelableExtra(ConnectivityManager
                .EXTRA_NETWORK_INFO);
        NetworkInfo info2 = (NetworkInfo) intent.getParcelableExtra(ConnectivityManager
                .EXTRA_OTHER_NETWORK_INFO);
        String reason = intent.getStringExtra(ConnectivityManager.EXTRA_REASON);
        boolean failOver = intent.getBooleanExtra(ConnectivityManager.EXTRA_IS_FAILOVER, false);
        Log.d("MY_TAG", "onReceive(): mNetworkInfo=" + info1 + " mOtherNetworkInfo = " +
                (info2 == null ? "[none]" : info2 + " noConn=" + noConnectivity));
    }
}

有关详细信息，请参阅此

http://code.google.com/p/androidwisprclient/source/browse/trunk/src/com/joan/pruebas/NetworkConnectivityListener.java?r=2

Answer 2

Dharmendras answer很好。但请注意，EXTRA_NETWORK_INFO现已弃用（自Api等级14以来），Android文档会说明以下内容：

由于NetworkInfo可能因UID而异，因此应用程序应始终通过getActiveNetworkInfo()获取网络信息。

这实际上让我们很容易。您可以重复使用之前可能执行的连接检查，并执行以下操作：

private class ConnectivityBroadcastReceiver extends BroadcastReceiver {

    @Override
    public void onReceive(Context context, Intent intent) {
        unregisterReceiver(this)
        checkConnection();
    }
}

private void checkConnection() {
    ConnectivityManager cm = (ConnectivityManager) getSystemService(CONNECTIVITY_SERVICE);
    if (cm.getActiveNetworkInfo() != null && cm.getActiveNetworkInfo()
            .isConnectedOrConnecting()) {
        // do something
    }
}

_{假设您在注册广播的活动中。}

这还有一个额外的好处，即尽可能短暂地监听连接广播的最佳实践，outlined here：）

用于CONNECTIVITY_ACTION的BroadcastReceiver始终在intent.getExtras（）中返回null

2 个答案: