Detect network changes

app/src/main/AndroidManifest.xml

@@ -23,15 +23,21 @@
           android:versionName="1.7.1">
 
     <uses-permission android:name="android.permission.VIBRATE"/>
+
     <uses-permission
         android:name="android.permission.READ_EXTERNAL_STORAGE"
         android:maxSdkVersion="18"/>
+
     <uses-permission
         android:name="android.permission.WRITE_EXTERNAL_STORAGE"
         android:maxSdkVersion="18"/>
+
     <uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED"/>
+
     <uses-permission android:name="android.permission.INTERNET"/>
 
+    <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
+
     <application
         android:name=".HabitsApplication"
         android:allowBackup="true"

app/src/main/java/org/isoron/uhabits/receivers/ConnectivityReceiver.java

@@ -0,0 +1,52 @@
+/*
+ * Copyright (C) 2016 Álinson Santos Xavier <isoron@gmail.com>
+ *
+ * This file is part of Loop Habit Tracker.
+ *
+ * Loop Habit Tracker is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or (at your
+ * option) any later version.
+ *
+ * Loop Habit Tracker is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package org.isoron.uhabits.receivers;
+
+import android.content.*;
+import android.net.*;
+import android.support.annotation.*;
+
+import org.isoron.uhabits.*;
+import org.isoron.uhabits.sync.*;
+
+import static android.content.Context.*;
+
+public class ConnectivityReceiver extends BroadcastReceiver
+{
+    @Override
+    public void onReceive(@Nullable Context context, @Nullable Intent intent)
+    {
+        if (context == null) return;
+        if (intent == null) return;
+
+        AppComponent component =
+            ((HabitsApplication) context.getApplicationContext()).getComponent();
+
+        NetworkInfo networkInfo =
+            ((ConnectivityManager) context.getSystemService(
+                CONNECTIVITY_SERVICE)).getActiveNetworkInfo();
+
+        boolean isConnected =
+            (networkInfo != null && networkInfo.isConnectedOrConnecting());
+
+        SyncManager syncManager = component.getSyncManager();
+        syncManager.onNetworkStatusChanged(isConnected);
+    }
+}

app/src/main/java/org/isoron/uhabits/sync/SyncManager.java

@@ -40,6 +40,7 @@ import io.socket.emitter.*;
 
 import static io.socket.client.Socket.*;
 
+@AppScope
 public class SyncManager implements CommandRunner.Listener
 {
     public static final String EVENT_AUTH = "auth";
@@ -80,15 +81,20 @@ public class SyncManager implements CommandRunner.Listener
     @NonNull
     private CommandParser commandParser;
 
+    private boolean isListening;
+
     @Inject
     public SyncManager(@AppContext @NonNull Context context,
                        @NonNull Preferences prefs,
                        @NonNull CommandRunner commandRunner,
                        @NonNull CommandParser commandParser)
     {
+        Log.i("SyncManager", this.toString());
+
         this.prefs = prefs;
         this.commandRunner = commandRunner;
         this.commandParser = commandParser;
+        this.isListening = false;
 
         pendingConfirmation = new LinkedList<>();
         pendingEmit = new LinkedList<>(Event.getAll());
@@ -118,19 +124,31 @@ public class SyncManager implements CommandRunner.Listener
         if (readyToEmit) emitPending();
     }
 
+    public void onNetworkStatusChanged(boolean isConnected)
+    {
+        if(!isListening) return;
+        if(isConnected) socket.connect();
+        else socket.disconnect();
+    }
+
     public void startListening()
     {
         if (!prefs.isSyncFeatureEnabled()) return;
         if (groupKey.isEmpty()) return;
+        if (isListening) return;
 
+        isListening = true;
         socket.connect();
         commandRunner.addListener(this);
     }
 
     public void stopListening()
     {
+        if(!isListening) return;
+
         commandRunner.removeListener(this);
         socket.close();
+        isListening = false;
     }
 
     private void connect(@AppContext @NonNull Context context, String serverURL)

app/src/main/java/org/isoron/uhabits/sync/SyncService.java

@@ -21,11 +21,13 @@ package org.isoron.uhabits.sync;
 
 import android.app.*;
 import android.content.*;
+import android.net.*;
 import android.os.*;
 import android.support.v7.app.*;
 
 import org.isoron.uhabits.*;
 import org.isoron.uhabits.preferences.*;
+import org.isoron.uhabits.receivers.*;
 
 public class SyncService extends Service implements Preferences.Listener
 {
@@ -33,6 +35,8 @@ public class SyncService extends Service implements Preferences.Listener
 
     private Preferences prefs;
 
+    private ConnectivityReceiver connectivityReceiver;
+
     public SyncService()
     {
     }
@@ -59,6 +63,10 @@ public class SyncService extends Service implements Preferences.Listener
 
         startForeground(99999, notification);
 
+        connectivityReceiver = new ConnectivityReceiver();
+        IntentFilter filter = new IntentFilter(ConnectivityManager.CONNECTIVITY_ACTION);
+        this.registerReceiver(connectivityReceiver, filter);
+
         HabitsApplication app = (HabitsApplication) getApplicationContext();
         syncManager = app.getComponent().getSyncManager();
         syncManager.startListening();
@@ -76,6 +84,7 @@ public class SyncService extends Service implements Preferences.Listener
     @Override
     public void onDestroy()
     {
+        unregisterReceiver(connectivityReceiver);
         syncManager.stopListening();
     }
 }