[android] set connectivity state pro-actively

platform/android/MapboxGLAndroidSDK/src/main/java/com/mapbox/mapboxsdk/MapboxAccountManager.java

@@ -8,6 +8,7 @@ import android.text.TextUtils;
 import com.mapbox.mapboxsdk.constants.MapboxConstants;
 import com.mapbox.mapboxsdk.exceptions.InvalidAccessTokenException;
 import com.mapbox.mapboxsdk.exceptions.MapboxAccountManagerNotStartedException;
+import com.mapbox.mapboxsdk.net.ConnectivityReceiver;
 import com.mapbox.mapboxsdk.telemetry.MapboxEventManager;
 
 public class MapboxAccountManager {
@@ -40,11 +41,16 @@ public class MapboxAccountManager {
      */
     public static MapboxAccountManager start(Context context, String accessToken) {
         if (mapboxAccountManager == null) {
+            //Create a new account manager
             mapboxAccountManager = new MapboxAccountManager(context, accessToken);
+
+            //Initialize the event manager
+            MapboxEventManager.getMapboxEventManager().initialize(context, accessToken);
+
+            //Register a receiver to listen for connectivity updates
+            ConnectivityReceiver.instance(context);
         }
 
-        MapboxEventManager eventManager = MapboxEventManager.getMapboxEventManager();
-        eventManager.initialize(mapboxAccountManager.applicationContext, mapboxAccountManager.accessToken);
         return mapboxAccountManager;
     }
 
@@ -92,8 +98,7 @@ public class MapboxAccountManager {
     public boolean isConnected() {
         ConnectivityManager cm = (ConnectivityManager) applicationContext.getSystemService(Context.CONNECTIVITY_SERVICE);
         NetworkInfo activeNetwork = cm.getActiveNetworkInfo();
-        boolean result = (activeNetwork != null && activeNetwork.isConnected());
-        return result;
+        return (activeNetwork != null && activeNetwork.isConnected());
     }
 
 }

platform/android/MapboxGLAndroidSDK/src/main/java/com/mapbox/mapboxsdk/net/ConnectivityListener.java

@@ -0,0 +1,10 @@
+package com.mapbox.mapboxsdk.net;
+
+/**
+ * Receives updates on connectivity state
+ */
+public interface ConnectivityListener {
+
+    void onNetworkStateChanged(boolean connected);
+
+}

platform/android/MapboxGLAndroidSDK/src/main/java/com/mapbox/mapboxsdk/net/ConnectivityReceiver.java

@@ -0,0 +1,88 @@
+package com.mapbox.mapboxsdk.net;
+
+import android.content.BroadcastReceiver;
+import android.content.Context;
+import android.content.Intent;
+import android.content.IntentFilter;
+import android.net.ConnectivityManager;
+import android.net.NetworkInfo;
+import android.support.annotation.NonNull;
+import android.util.Log;
+
+import java.util.List;
+import java.util.concurrent.CopyOnWriteArrayList;
+
+/**
+ * Interface definition for a callback to be invoked when connectivity changes.
+ * Not public api.
+ */
+public class ConnectivityReceiver extends BroadcastReceiver {
+    private static final String TAG = ConnectivityReceiver.class.getSimpleName();
+    private static ConnectivityReceiver INSTANCE;
+
+    /**
+     * Get or create the singleton instance
+     */
+    public static synchronized ConnectivityReceiver instance(Context context) {
+        if (INSTANCE == null) {
+            //Register new instance
+            INSTANCE = new ConnectivityReceiver();
+            context.registerReceiver(INSTANCE, new IntentFilter("android.net.conn.CONNECTIVITY_CHANGE"));
+
+            //Add default listeners
+            INSTANCE.addListener(new NativeConnectivityListener());
+        }
+
+        return INSTANCE;
+    }
+
+    private List<ConnectivityListener> listeners = new CopyOnWriteArrayList<>();
+
+    private ConnectivityReceiver() {
+    }
+
+    /**
+     * @see BroadcastReceiver#onReceive(Context, Intent)
+     */
+    @Override
+    public void onReceive(Context context, Intent intent) {
+        boolean connected = isConnected(context);
+        Log.v(TAG, "Connected: " + connected);
+
+        //Loop over listeners
+        for (ConnectivityListener listener : listeners) {
+            listener.onNetworkStateChanged(connected);
+        }
+    }
+
+    /**
+     * Add a listener to be notified
+     *
+     * @param listener the listener to add
+     */
+    public void addListener(@NonNull ConnectivityListener listener) {
+        listeners.add(listener);
+    }
+
+    /**
+     * Remove a listener
+     *
+     * @param listener the listener to remove
+     */
+    public void removeListener(@NonNull ConnectivityListener listener) {
+        listeners.remove(listener);
+    }
+
+    /**
+     * Get current connectivity state
+     *
+     * @param context current Context
+     * @return true if connected
+     */
+    public boolean isConnected(Context context) {
+        ConnectivityManager cm = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
+        NetworkInfo activeNetwork = cm.getActiveNetworkInfo();
+        return (activeNetwork != null && activeNetwork.isConnected());
+    }
+
+}

platform/android/MapboxGLAndroidSDK/src/main/java/com/mapbox/mapboxsdk/net/NativeConnectivityListener.java

@@ -0,0 +1,34 @@
+package com.mapbox.mapboxsdk.net;
+
+/**
+ * Updates the native library's connectivity state
+ */
+class NativeConnectivityListener implements ConnectivityListener {
+
+    static {
+        System.loadLibrary("mapbox-gl");
+    }
+
+    private long nativePtr;
+    private boolean invalidated;
+
+    NativeConnectivityListener(long nativePtr) {
+        this.nativePtr = nativePtr;
+    }
+
+    NativeConnectivityListener() {
+        initialize();
+    }
+
+    @Override
+    public void onNetworkStateChanged(boolean connected) {
+        nativeOnConnectivityStateChanged(connected);
+    }
+
+    protected native void nativeOnConnectivityStateChanged(boolean connected);
+
+    protected native void initialize();
+
+    @Override
+    protected native void finalize() throws Throwable;
+}