Added ChangedEvent.
diff --git a/ndn-cpp/util/changed-event.cpp b/ndn-cpp/util/changed-event.cpp
new file mode 100644
index 0000000..24a87bd
--- /dev/null
+++ b/ndn-cpp/util/changed-event.cpp
@@ -0,0 +1,19 @@
+/**
+ * Copyright (C) 2013 Regents of the University of California.
+ * @author: Jeff Thompson <jefft0@remap.ucla.edu>
+ * See COPYING for copyright and distribution information.
+ */
+
+#include "changed-event.hpp"
+
+using namespace std;
+
+namespace ndn {
+
+void ChangedEvent::fire()
+{
+ for (unsigned int i = 0; i < listeners_.size(); ++i)
+ listeners_[i]();
+}
+
+}