[ElmSharp] Fix RenderPost event remove Handler

 - evas event callback was not deleted when there is no more handler
 - EventHandler was null when there is no handler
 - So, should use GetInvocationList().Length to check exist of handler

Change-Id: I17bed9a3fea81bae6120c24cae476f33528a9053

diff --git a/src/ElmSharp/ElmSharp/EvasObject.cs b/src/ElmSharp/ElmSharp/EvasObject.cs
index 9c5b71b..83ace1b 100644 (file)
--- a/src/ElmSharp/ElmSharp/EvasObject.cs
+++ b/src/ElmSharp/ElmSharp/EvasObject.cs
@@ -216,7 +216,7 @@ namespace ElmSharp
             remove
             {
                 _renderPost -= value;
-                if (_renderPost?.GetInvocationList().Length == 0)
+                if (_renderPost == null)
                 {
                     Interop.Evas.evas_event_callback_del(Interop.Evas.evas_object_evas_get(RealHandle), Interop.Evas.ObjectCallbackType.RenderPost, _renderPostCallback);
                     _renderPostCallback = null;