diff --git a/include/nana/gui/msgbox.hpp b/include/nana/gui/msgbox.hpp
index ea60bcf6..fe6ae1ff 100644
--- a/include/nana/gui/msgbox.hpp
+++ b/include/nana/gui/msgbox.hpp
@@ -206,6 +206,9 @@ namespace nana
 
 			return _m_open(contents, true);
 		}
+
+		/// Sets a verifier to verify the user input.
+		void verify(std::function<bool(window)> verifier);
 	private:
 		void _m_fetch_args(std::vector<abstract_content*>&);
 
@@ -221,6 +224,7 @@ namespace nana
 		window owner_;
 		::nana::string description_;
 		::nana::string title_;
+		std::function<bool(window)> verifier_;
 	};
 }//end namespace nana
 
diff --git a/include/nana/gui/widgets/label.hpp b/include/nana/gui/widgets/label.hpp
index dc79eb1c..c6488e5b 100644
--- a/include/nana/gui/widgets/label.hpp
+++ b/include/nana/gui/widgets/label.hpp
@@ -69,6 +69,8 @@ namespace nana
 		/// "corrected" size that changes lines to fit the text into the specified width
 		nana::size measure(unsigned allowed_width_in_pixel) const;
 
+		static ::nana::size measure(::nana::paint::graphics&, const ::nana::string&, unsigned allowed_width_in_pixel, bool format_enabled, align h_align, align_v v_align);
+
 		label& text_align(align horizontal_align, align_v vertical_align= align_v::top);
 	private:
 		//Overrides widget's virtual function
diff --git a/include/nana/gui/widgets/spinbox.hpp b/include/nana/gui/widgets/spinbox.hpp
index f752c880..a1a85021 100644
--- a/include/nana/gui/widgets/spinbox.hpp
+++ b/include/nana/gui/widgets/spinbox.hpp
@@ -93,8 +93,8 @@ namespace nana
 		void range(double begin, double last, double step);
 
 		/// Sets the string spin values.
-		void range(std::initializer_list<std::string> steps_utf8);
-		void range(std::initializer_list<std::wstring> steps);
+		void range(std::initializer_list<std::string> values_utf8);
+		void range(std::initializer_list<std::wstring> values);
 
 		/// Gets the spined value
 		::nana::string value() const;
@@ -102,22 +102,9 @@ namespace nana
 		int to_int() const;
 		double to_double() const;
 
-		/// Sets a predicator that determines whether accepts the current user input.
-		/// @param pred Predicator to determines the input.
-		void set_accept(std::function<bool(::nana::char_t)> pred);
-
-		/// Sets the spinbox that only accepts integer input.
-		void set_accept_integer();
-
-		/// Sets the spinbox that only accepts real number input.
-		void set_accept_real();
-
-		/// Removes the accept excluding predicate accept.
-		void remove_accept();
-
-		/// Sets the qualifications
-		void qualify(std::wstring prefix, std::wstring suffix);
-		void qualify(const std::string & prefix_utf8, const std::string& suffix_utf8);
+		/// Sets the modifiers
+		void modifier(std::wstring prefix, std::wstring suffix);
+		void modifier(const std::string & prefix_utf8, const std::string& suffix_utf8);
 	private:
 		::nana::string _m_caption() const;
 		void _m_caption(::nana::string&&);
diff --git a/source/gui/detail/window_manager.cpp b/source/gui/detail/window_manager.cpp
index 27806ee4..f594e6a0 100644
--- a/source/gui/detail/window_manager.cpp
+++ b/source/gui/detail/window_manager.cpp
@@ -321,7 +321,7 @@ namespace detail
 			//Thread-Safe Required!
 			std::lock_guard<decltype(mutex_)> lock(mutex_);
 			if (impl_->wd_register.available(parent) == false)
-				return nullptr;
+				throw std::invalid_argument("invalid parent/owner handle");
 
 			core_window_t * wd;
 			if(is_lite)
diff --git a/source/gui/msgbox.cpp b/source/gui/msgbox.cpp
index e74a0b33..a13f3c82 100644
--- a/source/gui/msgbox.cpp
+++ b/source/gui/msgbox.cpp
@@ -20,6 +20,7 @@
 #include <nana/gui/place.hpp>
 #include <nana/datetime.hpp>
 #include <nana/internationalization.hpp>
+#include <functional>
 #if defined(NANA_WINDOWS)
 	#include <windows.h>
 #elif defined(NANA_X11)
@@ -473,7 +474,7 @@ namespace nana
 		: public ::nana::form
 	{
 	public:
-		inputbox_window(window owner, const ::nana::string & desc, const ::nana::string& title, std::size_t contents, unsigned fixed_pixels)
+		inputbox_window(window owner, const ::nana::string & desc, const ::nana::string& title, std::size_t contents, unsigned fixed_pixels, const std::vector<unsigned>& each_height)
 			: form(owner, API::make_center(owner, 500, 300), appear::decorate<>())
 		{
 			desc_.create(*this);
@@ -483,6 +484,10 @@ namespace nana
 			btn_ok_.create(*this);
 			btn_ok_.i18n(i18n_eval("OK"));
 			btn_ok_.events().click.connect_unignorable([this]{
+
+				if (verifier_ && !verifier_(handle()))
+					return;
+
 				close();
 				valid_input_ = true;
 			});
@@ -500,8 +505,15 @@ namespace nana
 			ss << "margin=10 vert <desc weight=" << desc_extent.height << "><vert margin=[10]";
 			
 			for (std::size_t i = 0; i < contents; ++i)
-				ss << "<weight=27 margin=[3] input_"<<i<<">";
-			height += 28 * contents;
+			{
+				unsigned px = 27;
+				if (each_height[i] > 27)
+					px = each_height[i];
+
+				ss << "<weight="<<px<<" margin=[3] input_" << i << ">";
+
+				height += px + 1;
+			}
 
 			ss << "><margin=[15] weight=38<><buttons arrange=80 gap=10 weight=170>>";
 
@@ -520,8 +532,10 @@ namespace nana
 			caption(title);
 		}
 
-		void set_input(const std::vector<window>& inputs)
+		void set_input(const std::vector<window>& inputs, std::function<bool(window)> verifier)
 		{
+			verifier_ = std::move(verifier);
+
 			std::size_t index = 0;
 			for (auto wd : inputs)
 			{
@@ -543,6 +557,7 @@ namespace nana
 		::nana::button	btn_cancel_;
 		bool	valid_input_{ false };
 		::nana::place	place_;
+		std::function<bool(window)> verifier_;
 	};
 
 	//class integer
@@ -603,7 +618,7 @@ namespace nana
 
 		impl->spinbox.create(impl->dock, rectangle{ static_cast<int>(label_px + 10), 0, value_px, 0 });
 		impl->spinbox.range(impl->begin, impl->last, impl->step);
-		impl->spinbox.set_accept_integer();
+		//impl->spinbox.set_accept_integer(); //deprecated
 
 		//Workaround for no implementation of std::to_wstring by MinGW.
 		ss.str(L"");
@@ -613,8 +628,8 @@ namespace nana
 
 		impl->dock.events().resized.connect_unignorable([impl, label_px, value_px](const ::nana::arg_resized& arg)
 		{
-			impl->label.size({ label_px, arg.height });
-			impl->spinbox.size({ value_px, arg.height });
+			impl->label.size({ label_px, 24 });
+			impl->spinbox.size({ value_px, 24 });
 		});
 
 		impl->spinbox.events().destroy.connect_unignorable([impl]
@@ -690,7 +705,7 @@ namespace nana
 
 		impl->spinbox.create(impl->dock, rectangle{ static_cast<int>(label_px + 10), 0, value_px, 0 });
 		impl->spinbox.range(impl->begin, impl->last, impl->step);
-		impl->spinbox.set_accept_real();
+		//impl->spinbox.set_accept_real();	//deprecated
 
 		//Workaround for no implementation of std::to_wstring by MinGW.
 		ss.str(L"");
@@ -700,8 +715,8 @@ namespace nana
 
 		impl->dock.events().resized.connect_unignorable([impl, label_px, value_px](const ::nana::arg_resized& arg)
 		{
-			impl->label.size({ label_px, arg.height });
-			impl->spinbox.size({ value_px, arg.height });
+			impl->label.size({ label_px, 24 });
+			impl->spinbox.size({ value_px, 24 });
 		});
 
 		impl->spinbox.events().destroy.connect_unignorable([impl]
@@ -790,15 +805,17 @@ namespace nana
 
 			for (auto & s : impl->options)
 				impl->combox.push_back(s);
+
+			impl->combox.option(0);
 		}
 
 		impl->dock.events().resized.connect_unignorable([impl, label_px, value_px](const ::nana::arg_resized& arg)
 		{
 			impl->label.size({ label_px, arg.height });
 			if (value_px)
-				impl->combox.size({ value_px, arg.height });
+				impl->combox.size({ value_px, 24 });
 			else
-				impl->textbox.size({arg.width - label_px - 10, arg.height});
+				impl->textbox.size({arg.width - label_px - 10, 24});
 		});
 
 		auto & wdg = (value_px ? static_cast<widget&>(impl->combox) : static_cast<widget&>(impl->textbox));
@@ -890,12 +907,12 @@ namespace nana
 		left += 104;
 		impl->wdg_day.create(impl->dock, rectangle{ left, 0, 38, 0 });
 		impl->wdg_day.range(1, ::nana::date::month_days(today.year, today.month), 1);
-		impl->wdg_day.set_accept_integer();
+		//impl->wdg_day.set_accept_integer();	//deprecated
 
 		left += 48;
 		impl->wdg_year.create(impl->dock, rectangle{left, 0, 50, 0});
 		impl->wdg_year.range(1601, 9999, 1);
-		impl->wdg_year.set_accept_integer();
+		//impl->wdg_year.set_accept_integer();	//deprecated
 
 		impl->wdg_month.option(today.month - 1);
 
@@ -911,15 +928,15 @@ namespace nana
 		{
 			impl->label.size({ label_px, arg.height });
 			auto sz = impl->wdg_month.size();
-			sz.height = arg.height;
+			sz.height = 24;
 			impl->wdg_month.size(sz);
 
 			sz = impl->wdg_day.size();
-			sz.height = arg.height;
+			sz.height = 24;
 			impl->wdg_day.size(sz);
 
 			sz = impl->wdg_year.size();
-			sz.height = arg.height;
+			sz.height = 24;
 			impl->wdg_year.size(sz);
 		});
 
@@ -970,35 +987,40 @@ namespace nana
 			title_(std::move(title))
 	{}
 
+	void inputbox::verify(std::function<bool(window)> verifier)
+	{
+		verifier_ = std::move(verifier);
+	}
+
 	void inputbox::_m_fetch_args(std::vector<abstract_content*>&)
 	{}
 
 
 	bool inputbox::_m_open(std::vector<abstract_content*>& contents, bool modal)
 	{
+		std::vector<unsigned> each_pixels;
 		unsigned label_px = 0, fixed_px = 0;
 		paint::graphics graph({ 5, 5 });
 		for (auto p : contents)
 		{
-			auto px = graph.text_extent_size(p->label()).width;
-			if (px > label_px)
-				label_px = px;
+			auto px = label::measure(graph, p->label(), 150, true, align::right, align_v::center);
+			if (px.width > label_px)
+				label_px = px.width;
 
-			px = p->fixed_pixels();
-			if (px > fixed_px)
-				fixed_px = px;
+			px.width = p->fixed_pixels();
+			if (px.width > fixed_px)
+				fixed_px = px.width;
+
+			each_pixels.push_back(px.height);
 		}
 
-		if (label_px > 120)
-			label_px = 120;
-
-		inputbox_window input_wd(owner_, description_, title_, contents.size(), label_px + 10 + fixed_px);
+		inputbox_window input_wd(owner_, description_, title_, contents.size(), label_px + 10 + fixed_px, each_pixels);
 
 		std::vector<window> inputs;
 		for (auto p : contents)
 			inputs.push_back(p->create(input_wd, label_px));
 
-		input_wd.set_input(inputs);
+		input_wd.set_input(inputs, verifier_);
 
 		if (modal)
 			input_wd.modality();
diff --git a/source/gui/widgets/label.cpp b/source/gui/widgets/label.cpp
index e6969835..8c534c67 100644
--- a/source/gui/widgets/label.cpp
+++ b/source/gui/widgets/label.cpp
@@ -837,6 +837,14 @@ namespace nana
 			return impl->renderer.measure(*graph_ptr, limited, impl->text_align, impl->text_align_v);
 		}
 
+		::nana::size label::measure(paint::graphics& graph, const ::nana::string& str, unsigned allowed_width_in_pixel, bool format_enabled, align h_align, align_v v_align)
+		{
+			drawerbase::label::renderer rd;
+			rd.format(format_enabled);
+			rd.parse(str);
+			return rd.measure(graph, allowed_width_in_pixel, h_align, v_align);
+		}
+
 		label& label::text_align(align th, align_v tv)
 		{
 			internal_scope_guard isg;
diff --git a/source/gui/widgets/spinbox.cpp b/source/gui/widgets/spinbox.cpp
index 5981d0ea..94a11715 100644
--- a/source/gui/widgets/spinbox.cpp
+++ b/source/gui/widgets/spinbox.cpp
@@ -53,7 +53,11 @@ namespace nana
 				virtual ~range_interface() = default;
 
 				virtual std::wstring value() const = 0;
-				virtual bool value(const std::wstring&) = 0;
+
+				//sets a new value, the diff indicates whether the new value is different from the current value.
+				//returns true if the new value is acceptable.
+				virtual bool value(const std::wstring& new_value, bool& diff) = 0;
+
 				virtual bool check_value(const std::wstring&) const = 0;
 				virtual void spin(bool increase) = 0;
 			};
@@ -74,29 +78,57 @@ namespace nana
 					return ss.str();
 				}
 
-				bool value(const std::wstring& value_str) override
+				bool value(const std::wstring& value_str, bool & diff) override
 				{
 					std::wstringstream ss;
 					ss << value_str;
 
 					T v;
 					ss >> v;
-					if (begin_ <= v && v <= last_)
-					{
-						value_ = v;
-						return true;
-					}
-					return false;
+					if (v < begin_ || last_ < v)
+						return false;
+	
+					diff = (value_ != v);
+					value_ = v;
+					return true;
 				}
 
-				bool check_value(const std::wstring& value_str) const override
+				bool check_value(const std::wstring& str) const override
 				{
-					std::wstringstream ss;
-					ss << value_str;
+					if (str.empty())
+						return true;
 
-					T v;
-					ss >> v;
-					return (begin_ <= v && v <= last_);
+					auto size = str.size();
+					std::size_t pos = 0;
+					if (str[0] == '+' || str[0] == '-')
+						pos = 1;
+
+					if (std::is_same<T, int>::value)
+					{
+						for (; pos < size; ++pos)
+						{
+							auto ch = str[pos];
+							if (ch < '0' || '9' < ch)
+								return false;
+						}
+					}
+					else
+					{
+						bool dot = false;
+						for (; pos < size; ++pos)
+						{
+							auto ch = str[pos];
+							if (('.' == ch) && (!dot))
+							{
+								dot = true;
+								continue;
+							}
+
+							if (ch < '0' || '9' < ch)
+								return false;
+						}
+					}
+					return true;
 				}
 
 				void spin(bool increase) override
@@ -145,11 +177,12 @@ namespace nana
 					return texts_[pos_];
 				}
 
-				bool value(const std::wstring& value_str) override
+				bool value(const std::wstring& value_str, bool & diff) override
 				{
 					auto i = std::find(texts_.cbegin(), texts_.cend(), value_str);
 					if (i != texts_.cend())
 					{
+						diff = (*i == value_str);
 						pos_ = i - texts_.cbegin();
 						return true;
 					}
@@ -158,12 +191,15 @@ namespace nana
 
 				bool check_value(const std::wstring& str) const override
 				{
-					for (auto & s : texts_)
+					if (str.empty())
+						return true;
+
+					auto i = std::find_if(texts_.cbegin(), texts_.cend(), [&str](const std::wstring& value)
 					{
-						if (s.find(str) != s.npos)
-							return true;
-					}
-					return false;
+						return (value.find(str) != value.npos);
+					});
+
+					return (i != texts_.cend());
 				}
 
 				void spin(bool increase) override
@@ -198,7 +234,7 @@ namespace nana
 					timer_.elapse([this]
 					{
 						range_->spin(buttons::increase == spin_stated_);
-						_m_text();
+						reset_text();
 						API::update_window(editor_->window_handle());
 
 						auto intv = timer_.interval();
@@ -219,7 +255,15 @@ namespace nana
 					editor_->set_accept([this](::nana::char_t ch)
 					{
 						auto str = editor_->text();
-						str += ch;
+						auto pos = editor_->caret().x;
+						if (ch == '\b')
+						{
+							if (pos > 0)
+								str.erase(pos - 1, 1);
+						}
+						else
+							str.insert(pos, 1, ch);
+
 						return range_->check_value(str);
 					});
 
@@ -229,7 +273,7 @@ namespace nana
 					if (!range_)
 						range_.reset(new range_numeric<int>(0, 100, 1));
 
-					_m_text();
+					reset_text();
 
 					API::tabstop(wd);
 					API::eat_tabstop(wd, true);
@@ -251,10 +295,12 @@ namespace nana
 
 				bool value(const ::nana::string& value_str)
 				{
-					if (!range_->value(value_str))
+					bool diff;
+					if (!range_->value(value_str, diff))
 						return false;
-
-					_m_text();
+					
+					if (diff)
+						reset_text();
 					return true;
 				}
 
@@ -262,17 +308,17 @@ namespace nana
 				{
 					range_.swap(ptr);
 
-					_m_text();
+					reset_text();
 				}
 
-				void qualify(std::wstring&& prefix, std::wstring&& suffix)
+				void modifier(std::wstring&& prefix, std::wstring&& suffix)
 				{
-					surround_.prefix = std::move(prefix);
-					surround_.suffix = std::move(suffix);
+					modifier_.prefix = std::move(prefix);
+					modifier_.suffix = std::move(suffix);
 
 					if (editor_)
 					{
-						_m_text();
+						reset_text();
 						API::update_window(editor_->window_handle());
 					}
 				}
@@ -296,7 +342,7 @@ namespace nana
 				void mouse_wheel(bool upwards)
 				{
 					range_->spin(!upwards);
-					_m_text();
+					reset_text();
 				}
 
 				bool mouse_button(const ::nana::arg_mouse& arg, bool pressed)
@@ -315,10 +361,11 @@ namespace nana
 						{
 							API::capture_window(editor_->window_handle(), true);
 							range_->spin(buttons::increase == spin_stated_);
-							_m_text();
+							reset_text();
 							timer_.start();
 						}
-						_m_draw_spins(spin_stated_);
+						else
+							_m_draw_spins(spin_stated_);
 						return true;
 					}
 
@@ -369,16 +416,20 @@ namespace nana
 					else
 						editor_->text_area({ 2, 2, graph_->width() - spins_r.width - 2, spins_r.height - 2 });
 				}
-			private:
-				void _m_text()
+
+				void reset_text()
 				{
-					if (editor_)
-					{
-						std::wstring text = surround_.prefix + range_->value() + surround_.suffix;
-						editor_->text(std::move(text));
-						_m_draw_spins(spin_stated_);
-					}
+					if (!editor_)
+						return;
+
+					if (API::is_focus_window(editor_->window_handle()))
+						editor_->text(range_->value());
+					else
+						editor_->text(modifier_.prefix + range_->value() + modifier_.suffix);
+
+					_m_draw_spins(spin_stated_);
 				}
+			private:
 
 				::nana::rectangle _m_spins_area() const
 				{
@@ -436,11 +487,11 @@ namespace nana
 				std::unique_ptr<range_interface> range_;
 				::nana::timer timer_;
 
-				struct surround_data
+				struct modifiers
 				{
 					std::wstring prefix;
 					std::wstring suffix;
-				}surround_;
+				}modifier_;
 			};
 
 			//class drawer
@@ -469,8 +520,9 @@ namespace nana
 				impl_->render();
 			}
 
-			void drawer::focus(graph_reference, const arg_focus&)
+			void drawer::focus(graph_reference, const arg_focus& arg)
 			{
+				impl_->reset_text();
 				impl_->render();
 				impl_->editor()->reset_caret();
 				API::lazy_refresh();
@@ -521,7 +573,9 @@ namespace nana
 			{
 				if (impl_->editor()->respone_keyboard(arg.key))
 				{
-					impl_->draw_spins();
+					if (!impl_->value(impl_->editor()->text()))
+						impl_->draw_spins();
+
 					API::lazy_refresh();
 				}
 			}
@@ -619,46 +673,14 @@ namespace nana
 		return ::nana::stod(value());
 	}
 
-	void spinbox::set_accept(std::function<bool(::nana::char_t)> pred)
+	void spinbox::modifier(std::wstring prefix, std::wstring suffix)
 	{
-		internal_scope_guard lock;
-		auto editor = get_drawer_trigger().impl()->editor();
-		if (editor)
-			editor->set_accept(std::move(pred));
+		get_drawer_trigger().impl()->modifier(std::move(prefix), std::move(suffix));
 	}
 
-	void spinbox::set_accept_integer()
+	void spinbox::modifier(const std::string & prefix_utf8, const std::string& suffix_utf8)
 	{
-		using accepts = ::nana::widgets::skeletons::text_editor::accepts;
-		auto editor = get_drawer_trigger().impl()->editor();
-		if (editor)
-			editor->set_accept(accepts::integer);
-	}
-
-	void spinbox::set_accept_real()
-	{
-		using accepts = ::nana::widgets::skeletons::text_editor::accepts;
-		auto editor = get_drawer_trigger().impl()->editor();
-		if (editor)
-			editor->set_accept(accepts::real);
-	}
-
-	void spinbox::remove_accept()
-	{
-		using accepts = ::nana::widgets::skeletons::text_editor::accepts;
-		auto editor = get_drawer_trigger().impl()->editor();
-		if (editor)
-			editor->set_accept(accepts::no_restrict);
-	}
-
-	void spinbox::qualify(std::wstring prefix, std::wstring suffix)
-	{
-		get_drawer_trigger().impl()->qualify(std::move(prefix), std::move(suffix));
-	}
-
-	void spinbox::qualify(const std::string & prefix_utf8, const std::string& suffix_utf8)
-	{
-		qualify(static_cast<std::wstring>(::nana::charset(prefix_utf8, ::nana::unicode::utf8)), static_cast<std::wstring>(::nana::charset(suffix_utf8, ::nana::unicode::utf8)));
+		modifier(static_cast<std::wstring>(::nana::charset(prefix_utf8, ::nana::unicode::utf8)), static_cast<std::wstring>(::nana::charset(suffix_utf8, ::nana::unicode::utf8)));
 	}
 
 	::nana::string spinbox::_m_caption() const