BroadcastReceiver wird immer vom Netzwerk getrennt

Question

Ich habe Android Developers tutorial für Managing Network Usage gefolgt.
Scheint wie die BroadcastReceiver immer vom Netzwerk getrennt werden.
Ich habe versucht, meine App über AVD und ein Telefon über ADB verbunden, aber beide funktionieren nicht.
Ich habe auch das Beispiel heruntergeladen und nur zum Überprüfen kopieren, aber es scheint, es ist ein Fehler.
Ich lasse den Code, aber es ist das gleiche auf der Website.

import android.app.Activity; 
import android.content.BroadcastReceiver; 
import android.content.Context; 
import android.content.Intent; 
import android.content.IntentFilter; 
import android.content.SharedPreferences; 
import android.net.ConnectivityManager; 
import android.net.NetworkInfo; 
import android.os.AsyncTask; 
import android.os.Bundle; 
import android.preference.PreferenceManager; 
import android.webkit.WebView; 
import android.widget.Toast; 

import org.xmlpull.v1.XmlPullParserException; 

import java.io.IOException; 
import java.io.InputStream; 
import java.net.HttpURLConnection; 
import java.net.URL; 
import java.text.DateFormat; 
import java.text.SimpleDateFormat; 
import java.util.Calendar; 
import java.util.List; 

public class NetworkActivity extends Activity { 

    public static final String WIFI = "Wi-Fi"; 
    public static final String ANY = "Any"; 
    private static final String FEED_URL = "http://formulapassion.it/feed"; 

    private static boolean wifiConnected = false; 
    private static boolean mobileConnected = false; 
    public static boolean refreshDisplay = true; 

    public static String sPref = null; 

    private NetworkReceiver receiver = new NetworkReceiver(); 

    @Override 
    public void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 

     // Filter added dinamically 
     IntentFilter filter = new IntentFilter(ConnectivityManager.CONNECTIVITY_ACTION); 
     receiver = new NetworkReceiver(); 
     this.registerReceiver(receiver, filter); 
    } 

    @Override 
    public void onStart() { 
     super.onStart(); 

     SharedPreferences sharedPrefs = PreferenceManager.getDefaultSharedPreferences(this); 
     sPref = sharedPrefs.getString("listPref", "Wi-Fi"); 

     updateConnectedFlags(); 

     if (refreshDisplay) { 
      loadPage(); 
     } 
    } 

    @Override 
    public void onDestroy() { 
     super.onDestroy(); 
     if (receiver != null) { 
      this.unregisterReceiver(receiver); 
     } 
    } 

    private void updateConnectedFlags() { 
     ConnectivityManager connMgr = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE); 

     NetworkInfo activeInfo = connMgr.getActiveNetworkInfo(); 
     if (activeInfo != null && activeInfo.isConnected()) { 
      wifiConnected = activeInfo.getType() == ConnectivityManager.TYPE_WIFI; 
      mobileConnected = activeInfo.getType() == ConnectivityManager.TYPE_MOBILE; 
     } else { 
      wifiConnected = false; 
      mobileConnected = false; 
     } 
    } 

    private void loadPage() { 
     if (((sPref.equals(ANY)) && (wifiConnected || mobileConnected)) 
       || ((sPref.equals(WIFI)) && (wifiConnected))) { 
      new DownloadXmlTask().execute(FEED_URL); 
     } 
     else { 
      showErrorPage(); 
     } 
    } 

    private void showErrorPage() { 
     setContentView(R.layout.news_feed_webview); 

     // The specified network connection is not available. Displays error message. 
     WebView myWebView = (WebView) findViewById(R.id.main_webview); 
     myWebView.loadData("Errore! Nessuna connessione", 
       "text/html", null); 
    } 

    private class DownloadXmlTask extends AsyncTask<String, Void, String> { 
       /* */ 
    } 

    private String loadXmlFromNetwork(String urlString) throws XmlPullParserException, IOException { 
       /* */ 
    } 

    public class NetworkReceiver extends BroadcastReceiver { 

     @Override 
     public void onReceive(Context context, Intent intent) { 
      ConnectivityManager connMgr = 
        (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE); 
      NetworkInfo networkInfo = connMgr.getActiveNetworkInfo(); 

      if (WIFI.equals(sPref) && networkInfo != null 
        && networkInfo.getType() == ConnectivityManager.TYPE_WIFI) { 
       refreshDisplay = true; 
       Toast.makeText(context, "Connesso", Toast.LENGTH_SHORT).show(); 
      } else if (ANY.equals(sPref) && networkInfo != null) { 
       refreshDisplay = true; 
      } else { 
       refreshDisplay = false; 
       Toast.makeText(context, "Disconnesso", Toast.LENGTH_SHORT).show(); 
      } 

     } 
    } 
} 

und meine Manifest:

<?xml version="1.0" encoding="utf-8"?> 
<manifest xmlns:android="http://schemas.android.com/apk/res/android" 
    package=""> 

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

    <uses-sdk xmlns:tools="http://schemas.android.com/tools" 
     tools:overrideLibrary="android.support.v14.preference,android.support.v7.appcompat,android.support.v7.preference,android.support.graphics.drawable,android.support.compat,android.support.v4,android.support.coreutils,android.support.mediacompat,android.support.coreui,android.support.fragment,android.support.v7.recyclerview" /> 

    <application 
     android:allowBackup="true" 
     android:icon="@mipmap/ic_launcher" 
     android:label="@string/app_name" 
     android:supportsRtl="true" 
     android:theme="@style/Theme.MyCustomTheme.Light" > 
    <!-- android:theme="@style/Theme.AppCompat.Light"> --> 

     <activity 
      android:name=".MainActivity" > 
      <intent-filter> 
       <action android:name="android.intent.action.MAIN" /> 

       <category android:name="android.intent.category.LAUNCHER" /> 
      </intent-filter> 
     </activity> 

     <activity 
      android:name=".FirstTimeActivity" 
      android:theme="@style/Theme.AppCompat.NoActionBar" /> 

     <receiver android:name=".NetworkActivity$NetworkReceiver"> 
      <intent-filter> 
       <action android:name="android.net.conn.CONNECTIVITY_CHANGE" /> 
      </intent-filter> 
     </receiver> 

     <activity 
      android:name=".SettingsActivity" 
      android:parentActivityName=".MainActivity" > 
       <action android:name="android.intent.action.MANAGE_NETWORK_USAGE" /> 
       <category android:name="android.intent.category.DEFAULT" /> 
     </activity> 

     <activity android:name=".NetworkActivity"> 
     </activity> 

    </application> 

</manifest> 

Answer 1

Sie benötigen WiFi State Change Listener Aktion hinzufügen, wenn Sie mit einem WLAN verbunden sind wie folgt aus:

<receiver android:name=".NetworkActivity$NetworkReceiver"> 
      <intent-filter> 
       <action android:name="android.net.conn.CONNECTIVITY_CHANGE" /> 
       <action android:name="android.net.wifi.WIFI_STATE_CHANGED" /> 
      </intent-filter> 
</receiver>