diff --git a/include/nana/gui/detail/general_events.hpp b/include/nana/gui/detail/general_events.hpp
index cdb6ac3a..a6f17bc6 100644
--- a/include/nana/gui/detail/general_events.hpp
+++ b/include/nana/gui/detail/general_events.hpp
@@ -427,11 +427,12 @@ namespace nana
 		::nana::point pos;   ///< cursor position in the event window
 		::nana::mouse button;	///< indicates a button which triggers the event
 
-		bool left_button;    ///< mouse left button is pressed?
-		bool mid_button;     ///< mouse middle button is pressed?
-		bool right_button;   ///< mouse right button is pressed?
-		bool shift;          ///< keyboard Shift is pressed?
-		bool ctrl;           ///< keyboard Ctrl is pressed?
+		bool left_button;	///< mouse left button is pressed?
+		bool mid_button;	///< mouse middle button is pressed?
+		bool right_button;	///< mouse right button is pressed?
+		bool alt;			///< keyboard alt is pressed?
+		bool shift;			///< keyboard Shift is pressed?
+		bool ctrl;			///< keyboard Ctrl is pressed?
 
 		/// Checks if left button is operated,
 		bool is_left_button() const
@@ -521,7 +522,7 @@ namespace nana
 	struct arg_click : public event_arg
 	{
 		::nana::window window_handle;	///< A handle to the event window
-		bool by_mouse;					///< Determines whether the event is emitted by clicking mouse button
+		const arg_mouse* mouse_args;	///< If it is not null, it refers to the mouse arguments for click event emitted by mouse, nullptr otherwise.
 	};
 
     /// provides some fundamental events that every widget owns.
diff --git a/source/gui/detail/linux_X11/bedrock.cpp b/source/gui/detail/linux_X11/bedrock.cpp
index 2bcf5715..991cf8ef 100644
--- a/source/gui/detail/linux_X11/bedrock.cpp
+++ b/source/gui/detail/linux_X11/bedrock.cpp
@@ -467,8 +467,9 @@ namespace detail
 		arg.left_button		= ((Button1Mask & mask_state) != 0) || (::nana::mouse::left_button == arg.button) ;
 		arg.right_button	= ((Button2Mask & mask_state) != 0) || (::nana::mouse::right_button == arg.button);
 		arg.mid_button		= ((Button3Mask & mask_state) != 0) || (::nana::mouse::middle_button == arg.button);
-		arg.shift	= (ShiftMask & mask_state);
-		arg.ctrl	= (ControlMask & mask_state);
+		arg.alt		= ((Mod1Mask & mask_state) != 0);
+		arg.shift	= ги(ShiftMask & mask_state) != 0);
+		arg.ctrl	= ги(ControlMask & mask_state) != 0);
 
 	}
 
@@ -815,21 +816,24 @@ namespace detail
 					{
 						auto retain = msgwnd->together.events_ptr;
 
-						arg_mouse arg;
+						::nana::arg_mouse arg;
 						assign_arg(arg, msgwnd, message, xevent);
 
+						::nana::arg_click click_arg;
+
+						//the window_handle of click_arg is used as a flag to determinate whether to emit click event.
+						click_arg.window_handle = nullptr;
+						click_arg.mouse_args = &arg;
+
 						const bool hit = msgwnd->dimension.is_hit(arg.pos);
-						bool fire_click = false;
 						if(msgwnd == pressed_wd)
 						{
 							if((arg.button == ::nana::mouse::left_button) && hit)
 							{
 								msgwnd->flags.action = mouse_action::over;
-								arg_click arg;
-								arg.window_handle = reinterpret_cast<window>(msgwnd);
-								arg.by_mouse = true;
+
+								click_arg.window_handle = reinterpret_cast<window>(msgwnd);
 								emit_drawer(&drawer::click, msgwnd, arg, &context);
-								fire_click = true;
 							}
 						}
 					
@@ -845,13 +849,8 @@ namespace detail
 							arg.evt_code = event_code::mouse_up;
 							emit_drawer(&drawer::mouse_up, msgwnd, arg, &context);
 
-							if(fire_click)
-							{
-								arg_click arg;
-								arg.window_handle = reinterpret_cast<window>(msgwnd);
-								arg.by_mouse = true;
-								evt_ptr->click.emit(arg);
-							}
+							if(click_arg.window_handle)
+								evt_ptr->click.emit(click_arg);
 
 							if (brock.wd_manager().available(msgwnd))
 							{
@@ -859,13 +858,9 @@ namespace detail
 								evt_ptr->mouse_up.emit(arg);
 							}
 						}
-						else if(fire_click)
-						{
-							arg_click arg;
-							arg.window_handle = reinterpret_cast<window>(msgwnd);
-							arg.by_mouse = true;
-							msgwnd->together.events_ptr->click.emit(arg);
-						}
+						else if(click_arg.window_handle)
+							msgwnd->together.events_ptr->click.emit(click_arg);
+
 						brock.wd_manager().do_lazy_refresh(msgwnd, false);
 					}
 					pressed_wd = nullptr;
diff --git a/source/gui/detail/win32/bedrock.cpp b/source/gui/detail/win32/bedrock.cpp
index 2a68f95a..7cdd1b5f 100644
--- a/source/gui/detail/win32/bedrock.cpp
+++ b/source/gui/detail/win32/bedrock.cpp
@@ -536,6 +536,7 @@ namespace detail
 		{
 			arg.pos.x = pmdec.mouse.x - wd->pos_root.x;
 			arg.pos.y = pmdec.mouse.y - wd->pos_root.y;
+			arg.alt = (::GetKeyState(VK_MENU) < 0);
 			arg.shift = pmdec.mouse.button.shift;
 			arg.ctrl = pmdec.mouse.button.ctrl;
 			arg.left_button = pmdec.mouse.button.left;
@@ -1001,20 +1002,22 @@ namespace detail
 				{
 					auto retain = msgwnd->together.events_ptr;
 
-					nana::arg_mouse arg;
+					::nana::arg_mouse arg;
 					assign_arg(arg, msgwnd, message, pmdec);
 
-					bool fire_click = false;
+					::nana::arg_click click_arg;
+
+					//the window_handle of click_arg is used as a flag to determinate whether to emit click event
+					click_arg.window_handle = nullptr;
+					click_arg.mouse_args = &arg;
+
 					if (msgwnd->dimension.is_hit(arg.pos))
 					{
 						msgwnd->flags.action = mouse_action::over;
 						if (::nana::mouse::left_button == arg.button)
 						{
-							arg_click arg;
-							arg.window_handle = reinterpret_cast<window>(msgwnd);
-							arg.by_mouse = true;
-							emit_drawer(&drawer::click, msgwnd, arg, &context);
-							fire_click = true;
+							click_arg.window_handle = reinterpret_cast<window>(msgwnd);
+							emit_drawer(&drawer::click, msgwnd, click_arg, &context);
 						}
 					}
 
@@ -1024,13 +1027,8 @@ namespace detail
 						arg.evt_code = event_code::mouse_up;
 						emit_drawer(&drawer::mouse_up, msgwnd, arg, &context);
 
-						if (fire_click)
-						{
-							arg_click arg;
-							arg.window_handle = reinterpret_cast<window>(msgwnd);
-							arg.by_mouse = true;
-							retain->click.emit(arg);
-						}
+						if (click_arg.window_handle)
+							retain->click.emit(click_arg);
 
 						if (brock.wd_manager().available(msgwnd))
 						{
@@ -1038,13 +1036,9 @@ namespace detail
 							retain->mouse_up.emit(arg);
 						}
 					}
-					else if (fire_click)
-					{
-						arg_click arg;
-						arg.window_handle = reinterpret_cast<window>(msgwnd);
-						arg.by_mouse = true;
-						retain->click.emit(arg);
-					}
+					else if (click_arg.window_handle)
+						retain->click.emit(click_arg);
+
 					brock.wd_manager().do_lazy_refresh(msgwnd, false);
 				}
 				pressed_wd = nullptr;
diff --git a/source/gui/widgets/button.cpp b/source/gui/widgets/button.cpp
index e68d9a3b..65972433 100644
--- a/source/gui/widgets/button.cpp
+++ b/source/gui/widgets/button.cpp
@@ -373,7 +373,7 @@ namespace nana{	namespace drawerbase
 		{
 			arg_click arg;
 			arg.window_handle = wdg_->handle();
-			arg.by_mouse = false;
+			arg.mouse_args = nullptr;
 			API::emit_event(event_code::click, arg.window_handle, arg);
 		}