fix listbox thread-safe issue(#329)

include/nana/gui/widgets/listbox.hpp

@@ -1028,6 +1028,7 @@ namespace nana
 				template<typename T>
 				void append_model(const T& t)
 				{
+					nana::internal_scope_guard lock;
 					_m_try_append_model(const_virtual_pointer{ &t });
 					_m_update();
 				}

source/gui/widgets/listbox.cpp

@@ -5380,6 +5380,7 @@ namespace nana
 
 		void listbox::auto_draw(bool enabled) noexcept
 		{
+			internal_scope_guard lock;
 			auto & ess = _m_ess();
 			if (ess.auto_draw != enabled)
 			{
@@ -5390,6 +5391,7 @@ namespace nana
 
 		void listbox::scroll(bool to_bottom, size_type cat_pos)
 		{
+			internal_scope_guard lock;
 			auto & ess = _m_ess();
 			auto cats = this->size_categ();
 
@@ -5488,6 +5490,7 @@ namespace nana
 
 		rectangle listbox::content_area() const
 		{
+			internal_scope_guard lock;
 			auto & ess = _m_ess();
 			auto carea = ess.content_area();
 			carea.x += ess.header.margin();
@@ -5534,29 +5537,34 @@ namespace nana
 
 		listbox::cat_proxy listbox::at(size_type pos)
 		{
+			internal_scope_guard lock;
 			check_range(pos, size_categ());
 			return{ &_m_ess(), pos };
 		}
 
 		const listbox::cat_proxy listbox::at(size_type pos) const
 		{
+			internal_scope_guard lock;
 			check_range(pos, size_categ());
 			return{ &_m_ess(), pos };
 		}
 
 		listbox::item_proxy listbox::at(const index_pair& abs_pos)
 		{
+			internal_scope_guard lock;
 			return at(abs_pos.cat).at(abs_pos.item);
 		}
 
 		const listbox::item_proxy listbox::at(const index_pair& pos_abs) const
 		{
+			internal_scope_guard lock;
 			return at(pos_abs.cat).at(pos_abs.item);
 		}
 
 		// Contributed by leobackes(pr#97)
 		listbox::index_pair listbox::cast( const point& pos ) const
 		{
+			internal_scope_guard lock;
 			auto & ess=_m_ess();
 			auto _where = ess.where(pos);
 
@@ -5568,27 +5576,32 @@ namespace nana
 
 		auto listbox::column_at(size_type pos, bool disp_order) -> column_interface&
 		{
+			internal_scope_guard lock;
 			return _m_ess().header.at(pos, disp_order);
 		}
 
 		auto listbox::column_at(size_type pos, bool disp_order) const -> const column_interface&
 		{
+			internal_scope_guard lock;
 			return _m_ess().header.at(pos, disp_order);
 		}
 
 		auto listbox::column_size() const ->size_type
 		{
+			internal_scope_guard lock;
 			return _m_ess().header.cont().size();
 		}
 
 		//Contributed by leobackes(pr#97)
 		listbox::size_type listbox::column_from_pos ( const point& pos ) const
 		{
+			internal_scope_guard lock;
 			return _m_ess().column_from_pos(pos.x);
 		}
 
 		void listbox::checkable(bool chkable)
 		{
+			internal_scope_guard lock;
 			auto & ess = _m_ess();
 			if(ess.checkable != chkable)
 			{
@@ -5599,11 +5612,13 @@ namespace nana
 
 		auto listbox::checked() const -> index_pairs
 		{
+			internal_scope_guard lock;
 			return _m_ess().lister.pick_items(false);
 		}
 
 		void listbox::clear(size_type cat)
 		{
+			internal_scope_guard lock;
 			auto & ess = _m_ess();
 
 			auto origin = ess.content_view->origin();
@@ -5627,6 +5642,7 @@ namespace nana
 
 		void listbox::clear()
 		{
+			internal_scope_guard lock;
 			auto & ess = _m_ess();
 
 			ess.lister.clear();
@@ -5641,6 +5657,7 @@ namespace nana
 
 		void listbox::erase(size_type cat)
 		{
+			internal_scope_guard lock;
 			auto & ess = _m_ess();
 
 			auto origin = ess.content_view->origin();
@@ -5665,6 +5682,7 @@ namespace nana
 
 		void listbox::erase()
 		{
+			internal_scope_guard lock;
 			auto & ess = _m_ess();
 			ess.lister.erase();
 			ess.calc_content_size();
@@ -5673,6 +5691,8 @@ namespace nana
 		
 		void listbox::erase(index_pairs indexes)
 		{
+			internal_scope_guard lock;
+
 			std::sort(indexes.begin(), indexes.end(), [](const index_pair& pos1, const index_pair& pos2)
 			{
 				return (pos1 > pos2);
@@ -5722,6 +5742,7 @@ namespace nana
 			if(ip.empty())
 				return ip;
 
+			internal_scope_guard lock;
 			auto * ess = ip._m_ess();
 			auto _where = ip.pos();
 
@@ -5744,48 +5765,57 @@ namespace nana
 
 		bool listbox::sortable() const
 		{
+			internal_scope_guard lock;
 			return _m_ess().header.sortable();
 		}
 
 		void listbox::sortable(bool enable)
 		{
+			internal_scope_guard lock;
 			_m_ess().header.sortable(enable);
 		}
 
 		void listbox::set_sort_compare(size_type col, std::function<bool(const std::string&, nana::any*, const std::string&, nana::any*, bool reverse)> strick_ordering)
 		{
+			internal_scope_guard lock;
 			_m_ess().header.at(col).weak_ordering = std::move(strick_ordering);
 		}
 
         /// sort() and ivalidate any existing reference from display position to absolute item, that is: after sort() display offset point to different items
         void listbox::sort_col(size_type col, bool reverse)
 		{
+			internal_scope_guard lock;
 			_m_ess().lister.sort_column(col, &reverse);
 		}
 
 		auto listbox::sort_col() const -> size_type
 		{
+			internal_scope_guard lock;
 			return _m_ess().lister.sort_attrs().column;
 		}
 
         /// potencially ivalidate any existing reference from display position to absolute item, that is: after sort() display offset point to different items
 		void listbox::unsort()
 		{
+			internal_scope_guard lock;
 			this->sort_col(npos, false);
 		}
 
 		bool listbox::freeze_sort(bool freeze)
 		{
+			internal_scope_guard lock;
 			return !_m_ess().lister.active_sort(!freeze);
 		}
 
 		auto listbox::selected() const -> index_pairs
 		{
+			internal_scope_guard lock;
 			return _m_ess().lister.pick_items(true);   // absolute positions, no relative to display
 		}
 
 		void listbox::show_header(bool sh)
 		{
+			internal_scope_guard lock;
 			_m_ess().header.visible(sh);
 			_m_ess().update();
 		}
@@ -5797,6 +5827,7 @@ namespace nana
 
 		void listbox::move_select(bool upwards)  ///<Selects an item besides the current selected item in the display.
 		{
+			internal_scope_guard lock;
 			_m_ess().lister.move_select(upwards, true, true);
 			_m_ess().update();
 		}
@@ -5829,6 +5860,7 @@ namespace nana
 
 		listbox& listbox::category_icon(std::function<void(paint::graphics& graph, const rectangle& rt_icon, bool expanded)> icon_renderer)
 		{
+			internal_scope_guard lock;
 			_m_ess().ctg_icon_renderer.swap(icon_renderer);
 			_m_ess().update();
 			return *this;
@@ -5836,6 +5868,7 @@ namespace nana
 
 		listbox& listbox::category_icon(const paint::image& img_expanded, const paint::image&& img_collapsed)
 		{
+			internal_scope_guard lock;
 			_m_ess().ctg_icon_renderer = [img_expanded, img_collapsed](paint::graphics& graph, const rectangle& rt_icon, bool expanded)
 			{
 				if (expanded)