Fix conflicts in friendlist refresh.

app/src/main/java/org/communiquons/android/comunic/client/data/helpers/FriendsListHelper.java

@@ -14,6 +14,7 @@ import org.json.JSONArray;
 import org.json.JSONObject;
 
 import java.util.ArrayList;
+import java.util.concurrent.locks.ReentrantLock;
 
 /**
  * Friends list functions
@@ -32,6 +33,9 @@ public class FriendsListHelper {
     private FriendsListDbHelper fdbHelper;
     private Context mContext;
 
+    //Friends list access lock
+    public static ReentrantLock ListAccessLock = new ReentrantLock();
+
     /**
      * Public constructor
      *
@@ -56,10 +60,22 @@ public class FriendsListHelper {
     /**
      * Get and return the friends list
      *
-     * @return The list of firned
+     * @return The list of friends
      */
     public ArrayList<Friend> get() {
-        return fdbHelper.get_list();
+
+        //Acquire friends list lock
+        FriendsListHelper.ListAccessLock.lock();
+
+        //Fetch the list
+        ArrayList<Friend> list;
+        try {
+            list = fdbHelper.get_list();
+        } finally {
+            FriendsListHelper.ListAccessLock.unlock();
+        }
+
+        return list;
     }
 
     /**

app/src/main/java/org/communiquons/android/comunic/client/data/runnables/FriendRefreshLoopRunnable.java

@@ -47,10 +47,19 @@ public class FriendRefreshLoopRunnable implements Runnable {
                 //Get the latest version of the list
                 ArrayList<Friend> friendsList = friendsListHelper.download();
 
+                //Acquire a lock over the friend list
+                FriendsListHelper.ListAccessLock.lock();
+
+                try {
                     //Save it (only in case of success)
                     if (friendsList != null)
                         friendsDBHelper.update_list(friendsList);
 
+                } finally {
+                    //Release the lock
+                    FriendsListHelper.ListAccessLock.unlock();
+                }
+
                 try {
                     object.wait(500); //TODO: increase the value
                 } catch (Exception e) {