std::string_view

source/gui/programming_interface.cpp

@@ -393,8 +393,13 @@ namespace API
 		{
 			if (shortkey)
 			{
+#ifdef _nana_std_has_string_view
+				auto off_x = (shortkey_position ? graph.text_extent_size(std::string_view{ text.c_str(), shortkey_position }).width : 0);
+				auto key_px = static_cast<int>(graph.text_extent_size(std::wstring_view{ &shortkey, 1 }).width);
+#else
 				auto off_x = (shortkey_position ? graph.text_extent_size(text.c_str(), shortkey_position).width : 0);
 				auto key_px = static_cast<int>(graph.text_extent_size(&shortkey, 1).width);
+#endif
 
 				unsigned ascent, descent, inleading;
 				graph.text_metrics(ascent, descent, inleading);

source/gui/widgets/checkbox.cpp

@@ -78,7 +78,11 @@ namespace nana{ namespace drawerbase
 				}
 
 				//draw crook
+#ifdef _nana_std_has_string_view
+				auto txt_px = graph.text_extent_size(std::wstring_view( L"jN", 2 )).height + 2;
+#else
 				auto txt_px = graph.text_extent_size(L"jN", 2).height + 2;
+#endif
 				impl_->crook.draw(graph, wdg->bgcolor(), wdg->fgcolor(), rectangle(0, txt_px > 16 ? (txt_px - 16) / 2 : 0, 16, 16), API::element_state(*wdg));
 			}
 

source/gui/widgets/label.cpp

@@ -83,7 +83,11 @@ namespace nana
 
 					auto pre_font = graph.typeface();	//used for restoring the font
 
+#ifdef _nana_std_has_string_view
+					const unsigned def_line_pixels = graph.text_extent_size(std::wstring_view{ L" ", 1 }).height;
+#else
 					const unsigned def_line_pixels = graph.text_extent_size(L" ", 1).height;
+#endif
 
 					font_ = pre_font;
 					fblock_ = nullptr;
@@ -170,7 +174,11 @@ namespace nana
 
 					auto ft = graph.typeface();	//used for restoring the font
 
+#ifdef _nana_std_has_string_view
+					const unsigned def_line_pixels = graph.text_extent_size(std::wstring_view(L" ", 1)).height;
+#else
 					const unsigned def_line_pixels = graph.text_extent_size(L" ", 1).height;
+#endif
 
 					font_ = ft;
 					fblock_ = nullptr;

source/gui/widgets/skeletons/text_editor.cpp

@@ -3147,7 +3147,11 @@ namespace nana{	namespace widgets
 				maskstr.append(n, mask_char_);
 				return graph_.text_extent_size(maskstr);
 			}
+#ifdef _nana_std_has_string_view
+			return graph_.text_extent_size(std::basic_string_view<char_type>(str, n));
+#else
 			return graph_.text_extent_size(str, static_cast<unsigned>(n));
+#endif
 		}
 
 		bool text_editor::_m_adjust_view()
@@ -3500,7 +3504,12 @@ namespace nana{	namespace widgets
 				for (auto & ent : reordered)
 				{
 					std::size_t len = ent.end - ent.begin;
+
+#ifdef _nana_std_has_string_view
+					unsigned str_w = graph_.text_extent_size(std::wstring_view{ ent.begin, len }).width;
+#else
 					unsigned str_w = graph_.text_extent_size(ent.begin, len).width;
+#endif
 
 					if ((text_draw_pos.x + static_cast<int>(str_w) > text_area_.area.x) && (text_draw_pos.x < text_right))
 					{
@@ -3519,7 +3528,11 @@ namespace nana{	namespace widgets
 				for (auto & ent : reordered)
 				{
 					const auto len = ent.end - ent.begin;
+#ifdef _nana_std_has_string_view
+					auto ent_px = graph_.text_extent_size(std::wstring_view(ent.begin, len)).width;
+#else
 					auto ent_px = graph_.text_extent_size(ent.begin, len).width;
+#endif
 
 					extra_space = false;
 
@@ -3589,7 +3602,11 @@ namespace nana{	namespace widgets
 				auto pos = text_coord.x + text_len;
 				if (b.x != pos || text_coord.y != b.y)
 				{
+#ifdef _nana_std_has_string_view
+					auto whitespace_w = graph_.text_extent_size(std::wstring_view{ L" ", 1 }).width;
+#else
 					auto whitespace_w = graph_.text_extent_size(L" ", 1).width;
+#endif
 					graph_.rectangle(::nana::rectangle{ text_draw_pos, { whitespace_w, line_h_pixels } }, true);
 				}
 			}

source/gui/widgets/treebox.cpp

@@ -1163,7 +1163,11 @@ namespace nana
 
 				virtual unsigned item_height(graph_reference graph) const override
 				{
+#ifdef _nana_std_has_string_view
+					return graph.text_extent_size(std::wstring_view{ L"jH{", 3 }).height + 8;
+#else
 					return graph.text_extent_size(L"jH{", 3).height + 8;
+#endif
 				}
 
 				virtual unsigned item_width(graph_reference graph, const item_attribute_t& attr) const override