fix a notifier error that can't set icon from its exe file

source/paint/image.cpp

@@ -34,10 +34,27 @@
 #include "detail/image_bmp.hpp"
 #include "detail/image_ico.hpp"
 
+#include "image_accessor.hpp"
+
 namespace nana
 {
 namespace paint
 {
+#if defined(NANA_WINDOWS)
+	HICON image_accessor::icon(const nana::paint::image& img)
+	{
+		auto ico = dynamic_cast<paint::detail::image_ico*>(img.image_ptr_.get());
+		if (ico && ico->ptr())
+			return *(ico->ptr());
+		return nullptr;
+	}
+#else
+	int image_accessor::icon(const image&)
+	{
+		return 0;
+	}
+#endif
+
 	namespace detail
 	{
 		//class image_ico

source/paint/image_accessor.hpp

@@ -0,0 +1,30 @@
+/*
+*	Paint Image Accessor
+*	Nana C++ Library(http://www.nanapro.org)
+*	Copyright(C) 2003-2016 Jinhao(cnjinhao@hotmail.com)
+*
+*	Distributed under the Boost Software License, Version 1.0.
+*	(See accompanying file LICENSE_1_0.txt or copy at
+*	http://www.boost.org/LICENSE_1_0.txt)
+*
+*	@file nana/paint/image_accessor.hpp
+*	@brief A declaration of class image_accessor. It is used to access image private data, internal use.
+*/
+#ifndef NANA_PAINT_IMAGE_ACCESS_HEADER_INCLUDED
+#define NANA_PAINT_IMAGE_ACCESS_HEADER_INCLUDED
+namespace nana
+{
+	namespace paint
+	{
+		class image_accessor
+		{
+		public:
+#if defined(NANA_WINDOWS)
+			static HICON icon(const image&);
+#else
+			static int icon(const image&);
+#endif
+		};
+	}
+}
+#endif