fix the strange behavior of Korean ime composition window.

Because Hangul is a combination character, WM_IME_STARTCOMPOSITION is only called once when the IME input is started, so the position of the composition window is strange.

Therefore, I solved the problem by controlling the state of characters combined using WM_IME_COMPOSITION and WM_IME_CHAR.

We have also improved to support other IME languages such as Chinese and Japanese.

source/gui/widgets/combox.cpp

@@ -773,6 +773,13 @@ namespace nana
 				API::dev::lazy_refresh();
 			}
 
+			void trigger::key_ime(graph_reference, const arg_ime& arg)
+			{
+				drawer_->editor()->respond_ime(arg);
+				if (drawer_->editor()->try_refresh())
+					API::dev::lazy_refresh();
+			}
+
 			void trigger::key_char(graph_reference, const arg_keyboard& arg)
 			{
 				drawer_->editor()->respond_char(arg);

source/gui/widgets/skeletons/text_editor.cpp

@@ -1163,6 +1163,43 @@ namespace nana {
 				impl_->capacities.acceptive = acceptive;
 			}
 
+			bool text_editor::respond_ime(const arg_ime& arg)
+			{
+				if (!API::window_enabled(window_))
+					return false;
+
+				if (select_.a != select_.b)
+				{
+					points_.caret = _m_erase_select(false);
+				}
+
+				for (size_t i = 0; i < composition_size_; ++i)
+				{
+					backspace(false, false);
+				}
+
+				if (arg.ime_reason == arg_ime::reason::composition)
+				{
+					composition_size_ = arg.composition_string.length();
+					points_.caret = _m_put(std::move(arg.composition_string), false);
+
+					_m_reset_content_size(true);
+					textbase().text_changed();
+
+					if (this->_m_adjust_view())
+						impl_->cview->sync(false);
+
+					reset_caret();
+					impl_->try_refresh = sync_graph::refresh;
+				}
+				else
+				{
+					composition_size_ = 0;
+				}
+
+				return true;
+			}
+
 			bool text_editor::respond_char(const arg_keyboard& arg)	//key is a character of ASCII code
 			{
 				if (!API::window_enabled(window_))

source/gui/widgets/spinbox.cpp

@@ -621,6 +621,13 @@ namespace nana
 				API::dev::lazy_refresh();
 			}
 
+			void drawer::key_ime(graph_reference, const arg_ime& arg)
+			{
+				impl_->editor()->respond_ime(arg);
+				if (impl_->editor()->try_refresh())
+					API::dev::lazy_refresh();
+			}
+
 			void drawer::key_press(graph_reference, const arg_keyboard& arg)
 			{
 				if (impl_->editor()->respond_key(arg))

source/gui/widgets/textbox.cpp

@@ -152,6 +152,13 @@ namespace drawerbase {
 				API::dev::lazy_refresh();
 		}
 
+		void drawer::key_ime(graph_reference, const arg_ime& arg)
+		{
+			editor_->respond_ime(arg);
+			if (editor_->try_refresh())
+				API::dev::lazy_refresh();
+		}
+
 		void drawer::key_press(graph_reference, const arg_keyboard& arg)
 		{
 			editor_->respond_key(arg);