Android でネットワーク ステータスの変化とオフライン イベントを検出する方法

<code class="java">public class ConnectionChangeReceiver extends BroadcastReceiver {
    @Override
    public void onReceive(Context context, Intent intent) {
        ConnectivityManager connectivityManager = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
        NetworkInfo activeNetInfo = connectivityManager.getActiveNetworkInfo();
        NetworkInfo mobNetInfo = connectivityManager.getNetworkInfo(ConnectivityManager.TYPE_MOBILE);

        if (activeNetInfo != null) {
            Toast.makeText(context, "Active Network Type: " + activeNetInfo.getTypeName(), Toast.LENGTH_SHORT).show();
        }

        if (mobNetInfo != null) {
            Toast.makeText(context, "Mobile Network Type: " + mobNetInfo.getTypeName(), Toast.LENGTH_SHORT).show();
        }
    }
}</code>

<code class="xml"><uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" /></code>

<code class="xml"><receiver android:name="com.blackboard.androidtest.receiver.ConnectionChangeReceiver"
          android:label="NetworkConnection">
    <intent-filter>
        <action android:name="android.net.conn.CONNECTIVITY_CHANGE" />
    </intent-filter>
</receiver></code>

<code class="java">BroadcastReceiver receiver = new ConnectionChangeReceiver();
IntentFilter filter = new IntentFilter("android.net.conn.CONNECTIVITY_CHANGE");
context.registerReceiver(receiver, filter);</code>