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SDLmm::EventHandler(3)	   Library Functions Manual	SDLmm::EventHandler(3)

NAME
       SDLmm::EventHandler - The base class used for custom Event handlers.

SYNOPSIS
       #include	<sdlmm_eventhandler.h>

   Public Methods
       virtual bool HandleEvent	(SDL_Event &event)
	   Catch-all event handler.

       Keyboard	Events

	   virtual bool	HandleKeyboardEvent (SDL_keysym	&keysym, bool pressed)
	       Keyboard	event callback.
	   virtual bool	HandleKeyPressEvent (SDL_keysym	&keysym)
	       Keyboard	press event callback.
	   virtual bool	HandleKeyReleaseEvent (SDL_keysym &keysym)
	       Keyboard	release	event callback.

       Mouse Events

	   virtual bool	HandleMouseMotionEvent (Uint8 state, Uint16 x, Uint16
	       y, Sint16 xrel, Sint16 yrel)
	       Mouse motion event callback.
	   virtual bool	HandleMouseButtonEvent (Uint8 button, Uint16 x,	Uint16
	       y, bool pressed)
	       Mouse button event callback.
	   virtual bool	HandleMouseButtonPressEvent (Uint8 button, Uint16 x,
	       Uint16 y)
	       Mouse button press event	callback.
	   virtual bool	HandleMouseButtonReleaseEvent (Uint8 button, Uint16 x,
	       Uint16 y)
	       Mouse button release event callback.

       Joystick	Events

	   virtual bool	HandleJoyAxisEvent (Uint8 joystick, Uint8 axis,	Sint16
	       value)
	       Joystick	axis motion event callback.
	   virtual bool	HandleJoyButtonEvent (Uint8 joystick, Uint8 button,
	       bool pressed)
	       Joystick	button event callback.
	   virtual bool	HandleJoyButtonPressEvent (Uint8 joystick, Uint8
	       button)
	       Joystick	button press event callback.
	   virtual bool	HandleJoyButtonReleaseEvent (Uint8 joystick, Uint8
	       button)
	       Joystick	button release event callback.
	   virtual bool	HandleJoyHatEvent (Uint8 joystick, Uint8 hat, Uint8
	       value)
	       Joystick	hat position change event callback.
	   virtual bool	HandleJoyBallEvent (Uint8 joystick, Uint8 ball,	Sint16
	       xrel, Sint16 yrel)
	       Joystick	trackball motion event callback.

       Window /	Display	Events

	   virtual bool	HandleActiveEvent (bool	gain, Uint8 state)
	       Application visibility event callback.
	   virtual bool	HandleResizeEvent (int w, int h)
	       Window resize event callback.
	   virtual bool	HandleSysWMEvent ()
	       Platform-dependent window manager event callback.

       Other Events

	   virtual bool	HandleUserEvent	(Uint8 type, int code, void *data1,
	       void *data2)
	   virtual bool	HandleQuitEvent	()
	       Quit requested event callback.

DETAILED DESCRIPTION
       The base	class used for custom Event handlers.

       The event handling in SDLmm is rather different to that of SDL in  that
       it uses classes derived from the	EventHandler. This allows for clean,
       type-safe code much closer to the spirit	of C++ than the	use of a union
       with a type field. To handle one	or more	events,	you simply build a
       class derived from this,	reimplementing the only	functions for the
       events you need to handle.

       See also:
	   Event::HandleEvents()

MEMBER FUNCTION	DOCUMENTATION
   bool	SDLmm::EventHandler::HandleActiveEvent (bool gain, Uint8 state)
       [inline,	virtual]
       Application visibility event callback.

       This callback is	called when an event of	type SDL_ACTIVEEVENT is
       reported.

       When the	mouse leaves or	enters the window area a SDL_APPMOUSEFOCUS
       type activation event occurs, if	the mouse entered the window then gain
       will be true, otherwise gain will be false. A SDL_APPINPUTFOCUS type
       activation event	occurs when the	application loses or gains keyboard
       focus. This usually occurs when another application is made active.
       Finally,	a SDL_APPACTIVE	type event occurs when the application is
       either minimised/iconified (gain=false) or restored.

       Parameters:

       gain   false if the event is a loss or true if it's a gain

       state  SDL_APPMOUSEFOCUS	if mouse focus was gained or lost,
	      SDL_APPINPUTFOCUS	if input focus was gained or lost, or
	      SDL_APPACTIVE if the application was iconified (gain=false) or
	      restored (gain=true)

       Returns:
	   true	if the event was handled, false	if it was not. If the event
	   wasn't handled, it will be handed over to the generic HandleEvent()
	   method.

   bool	SDLmm::EventHandler::HandleEvent (SDL_Event & event) [inline, virtual]
       Catch-all event handler.

       This method is called if	none of	the event specific callbacks handled
       event (i.e they returned	false).

       Note:
	   It's	both easier and	more efficient to use the event-specific
	   callbacks, so unless	you really want	to do all the work yourself,
	   you want to use those.

       Parameters:

       event  the current event

       Returns:
	   true	if the event was handled, false	if it was not

   bool	SDLmm::EventHandler::HandleJoyAxisEvent	(Uint8 joystick, Uint8 axis,
       Sint16 value) [inline, virtual]
       Joystick	axis motion event callback.

       This is used when an event of type SDL_JOYAXISMOTION is reported.

       A SDL_JOYAXISMOTION event occurs	when ever a user moves an axis on the
       joystick.

       Parameters:

       joystick
	      the index	of the joystick	that reported the event

       axis   the index	of the axis (for a more	detailed explaination see the
	      Joystick section of the SDL manual).

       ams value is the	current	position of the	axis.

       Returns:
	   true	if the event was handled, false	if it was not. If the event
	   wasn't handled, it will be handed over to the generic HandleEvent()
	   method.

   bool	SDLmm::EventHandler::HandleJoyBallEvent	(Uint8 joystick, Uint8 ball,
       Sint16 xrel, Sint16 yrel) [inline, virtual]
       Joystick	trackball motion event callback.

       Thyis is	used when an event of type SDL_JOYBALLMOTION is	reported.

       A SDL_JOYBALLMOTION event occurs	when a user moves a trackball on the
       joystick. The field joystick is the index of the	joystick that reported
       the event and ball is the index of the trackball	(for a more detailed
       explaination see	the Joystick section in	the SDL	documentation).
       Trackballs only return relative motion, this is the change in position
       on the ball since it was	last polled (last cycle	of the event loop) and
       it is stored in xrel and	yrel.

       Parameters:

       joystick
	      joystick device index

       ball   joystick trackbal	index

       xrel, yrel
	      relative motion in the x/y directions

       Returns:
	   true	if the event was handled, false	if it was not. If the event
	   wasn't handled, it will be handed over to the generic HandleEvent()
	   method.

   bool	SDLmm::EventHandler::HandleJoyButtonEvent (Uint8 joystick, Uint8
       button, bool pressed) [inline, virtual]
       Joystick	button event callback.

       This is used when an event of type SDL_JOYBUTTONDOWN or SDL_JOYBUTTONUP
       is reported.

       These events occurs when	ever a user presses or releases	a button on a
       joystick.

       Note:
	   This	function is only called	if the default
	   HandleJoyButtonPressEvent() and / or	HandleJoyButtonReleaseEvent()
	   methods are used.

       Parameters:

       joystick
	      the index	of the joystick	that reported the event

       button the index	of the pressed button (for a more detailed
	      explaination see the Joystick section of the SDL manual).

       pressed
	      true for SDL_JOYBUTTONDOWN, false	for SDL_JOYBUTTONUP.

       Returns:
	   true	if the event was handled, false	if it was not. If the event
	   wasn't handled, it will be handed over to the generic HandleEvent()
	   method.

   bool	SDLmm::EventHandler::HandleJoyButtonPressEvent (Uint8 joystick,	Uint8
       button) [inline,	virtual]
       Joystick	button press event callback.

       This is used when an event of type SDL_JOYBUTTONDOWN is reported.

       A SDL_JOYBUTTONDOWN event occurs	when ever a user presses a button on a
       joystick.

       Note:
	   The default declaration of this method calls	the
	   HandleJoyButtonEvent() method. If you want to handle	both button
	   presses and releases	in the same method, just redefine
	   HandleJoyButtonEvent().

       Parameters:

       joystick
	      the index	of the joystick	that reported the event

       button the index	of the pressed button (for a more detailed
	      explaination see the Joystick section of the SDL manual).

       Returns:
	   true	if the event was handled, false	if it was not. If the event
	   wasn't handled, it will be handed over to the generic HandleEvent()
	   method.

   bool	SDLmm::EventHandler::HandleJoyButtonReleaseEvent (Uint8	joystick,
       Uint8 button) [inline, virtual]
       Joystick	button release event callback.

       This is used when an event of type SDL_JOYBUTTONUP is reported.

       A SDL_JOYBUTTONUP event occurs when ever	a user releases	a button on a
       joystick.

       Note:
	   The default declaration of this method calls	the
	   HandleJoyButtonEvent() method. If you want to handle	both button
	   presses and releases	in the same method, just redefine
	   HandleJoyButtonEvent().

       Parameters:

       joystick
	      the index	of the joystick	that reported the event

       button the index	of the released	button (for a more detailed
	      explaination see the Joystick section of the SDL manual).

       Returns:
	   true	if the event was handled, false	if it was not. If the event
	   wasn't handled, it will be handed over to the generic HandleEvent()
	   method.

   bool	SDLmm::EventHandler::HandleJoyHatEvent (Uint8 joystick,	Uint8 hat,
       Uint8 value) [inline, virtual]
       Joystick	hat position change event callback.

       This is used when an event of type SDL_JOYHATMOTION is reported.

       A SDL_JOYHATMOTION event	occurs when ever a user	moves a	hat on the
       joystick. The field joystick is the index of the	joystick that reported
       the event and hat is the	index of the hat (for a	more detailed
       exlaination see the Joystick section in the SDL documentation). value
       is the current position of the hat. It is a logically OR'd combination
       of the following	values (whose meanings should be pretty	obvious):

       SDL_HAT_CENTERED

       SDL_HAT_UP

       SDL_HAT_RIGHT

       SDL_HAT_DOWN

       SDL_HAT_LEFT

       The following defines are also provided:

       SDL_HAT_RIGHTUP

       SDL_HAT_RIGHTDOWN

       SDL_HAT_LEFTUP

       SDL_HAT_LEFTDOWN

       Parameters:

       joystick
	      joystick device index

       hat    joystick hat index

       value  hat position

       Returns:
	   true	if the event was handled, false	if it was not. If the event
	   wasn't handled, it will be handed over to the generic HandleEvent()
	   method.

   bool	SDLmm::EventHandler::HandleKeyPressEvent (SDL_keysym & keysym)
       [inline,	virtual]
       Keyboard	press event callback.

       This callback is	used when an event of type SDL_KEYDOWN is reported. A
       keyboard	press event occurs when	a key is pressed.

       Note:
	   Repeating SDL_KEYDOWN events	will occur if key repeat is enabled
	   (see	EnableKeyRepeat()).
	   The default declaration of this method calls	the
	   HandleKeyboardEvent() method. If you	want to	handle both key
	   presses and key releases in the same	method,	just redefine
	   HandleKeyboardEvent().

       Parameters:

       keysym information about	the pressed key

       Returns:
	   true	if the event was handled, false	if it was not. If the event
	   wasn't handled, it will be handed over to the generic HandleEvent()
	   method.

   bool	SDLmm::EventHandler::HandleKeyReleaseEvent (SDL_keysym & keysym)
       [inline,	virtual]
       Keyboard	release	event callback.

       This callback is	used when an event of type SDL_KEYUP is	reported. A
       keyboard	press event occurs when	a key is released.

       Parameters:

       keysym the information about the	released key

       Note:
	   The default declaration of this method calls	the
	   HandleKeyboardEvent() method. If you	want to	handle both key
	   presses and releases	in the same method, just redefine
	   HandleKeyboardEvent().

       Returns:
	   true	if the event was handled, false	if it was not. If the event
	   wasn't handled, it will be handed over to the generic HandleEvent()
	   method.

   bool	SDLmm::EventHandler::HandleKeyboardEvent (SDL_keysym & keysym, bool
       pressed)	[inline, virtual]
       Keyboard	event callback.

       This callback is	used when an event of type SDL_KEYDOWN or SDL_KEYUP is
       reported. These occur when keys are pressed or released.

       Note:
	   Repeating SDL_KEYDOWN events	will occur if key repeat is enabled
	   (see	EnableKeyRepeat()).
	   This	function is only called	if the default HandleKeyPressEvent()
	   and / or HandleKeyReleaseEvent() methods are	used.

       Parameters:

       keysym information about	the pressed key

       pressed
	      true for SDL_KEYDOWN, false for SDL_KEYUP

       Returns:
	   true	if the event was handled, false	if it was not. If the event
	   wasn't handled, it will be handed over to the generic HandleEvent()
	   method.

   bool	SDLmm::EventHandler::HandleMouseButtonEvent (Uint8 button, Uint16 x,
       Uint16 y, bool pressed) [inline,	virtual]
       Mouse button event callback.

       This is used when an event of type SDL_MOUSEBUTTONDOWN or
       SDL_MOUSEBUTTONUP is reported.

       When a mouse button press is detected the number	of the button pressed
       (from 1 to 255, with 1 usually being the	left button and	2 the right)
       is placed into button. The position of the mouse	when this event
       occured is stored in x and y.

       Note:
	   This	function is only called	if the default
	   HandleMouseButtonPressEvent() and / or
	   HandleMouseButtonReleaseEvent() methods are used.

       Parameters:

       button the mouse	button index

       x, y   the x/y coordinates of the mouse at press	time

       pressed
	      true for SDL_MOUSEBUTTONDOWN, false for SDL_MOUSEBUTTONUP.

       Returns:
	   true	if the event was handled, false	if it was not. If the event
	   wasn't handled, it will be handed over to the generic HandleEvent()
	   method.

   bool	SDLmm::EventHandler::HandleMouseButtonPressEvent (Uint8	button,	Uint16
       x, Uint16 y) [inline, virtual]
       Mouse button press event	callback.

       This is used when an event of type SDL_MOUSEBUTTONDOWN is reported.

       When a mouse button press is detected the number	of the button pressed
       (from 1 to 255, with 1 usually being the	left button and	2 the right)
       is placed into button. The position of the mouse	when this event
       occured is stored in x and y.

       Note:
	   The default declaration of this method calls	the
	   HandleMouseButtonEvent() method. If you want	to handle both button
	   presses and releases	in the same method, just redefine
	   HandleMouseButtonEvent().

       Parameters:

       button the mouse	button index

       x, y   the x/y coordinates of the mouse at press	time

       Returns:
	   true	if the event was handled, false	if it was not. If the event
	   wasn't handled, it will be handed over to the generic HandleEvent()
	   method.

   bool	SDLmm::EventHandler::HandleMouseButtonReleaseEvent (Uint8 button,
       Uint16 x, Uint16	y) [inline, virtual]
       Mouse button release event callback.

       This is used when an event of type SDL_MOUSEBUTTONUP is reported.

       When a mouse button release is detected the number of the button
       release (from 1 to 255, with 1 usually being the	left button and	2 the
       right) is placed	into button. The position of the mouse when this event
       occured is stored in x and y.

       Note:
	   The default declaration of this method calls	the
	   HandleMouseButtonEvent() method. If you want	to handle both button
	   presses and releases	in the same method, just redefine
	   HandleMouseButtonEvent().

       Parameters:

       button the mouse	button index

       x, y   the x/y coordinates of the mouse at press	time

       Returns:
	   true	if the event was handled, false	if it was not. If the event
	   wasn't handled, it will be handed over to the generic HandleEvent()
	   method.

   bool	SDLmm::EventHandler::HandleMouseMotionEvent (Uint8 state, Uint16 x,
       Uint16 y, Sint16	xrel, Sint16 yrel) [inline, virtual]
       Mouse motion event callback.

       This is used when an event of type SDL_MOUSEMOTION is reported.

       Simply put, a SDL_MOUSEMOTION type event	occurs when a user moves the
       mouse within the	application window or when SDL_WarpMouse is called.
       Both the	absolute (x and	y) and relative	(xrel and yrel)	coordinates
       are reported along with the current button states (state). The button
       state can be interpreted	using the SDL_BUTTON macro (see
       GetMouseState()).

       If the cursor is	hidden (Display::HideCursor()) and the input is
       grabbed (Display::GrabInput(SDL_GRAB_ON)) then the mouse	will give
       relative	motion events even when	the cursor reaches the edge of the
       screen. This is currently only implemented on Windows and Linux/Unix-a-
       likes.

       Parameters:

       state  the current button state.

       x, y   the absolute x/y coordinates of the mouse	pointer

       xrel, yrel
	      relative motion in the x/y directions

       Returns:
	   true	if the event was handled, false	if it was not. If the event
	   wasn't handled, it will be handed over to the generic HandleEvent()
	   method.

   bool	SDLmm::EventHandler::HandleQuitEvent ()	[inline, virtual]
       Quit requested event callback.

       This is used whan an event of type SDL_QUIT is reported.

       The SDL_QUIT event is very important. If	you filter out or ignore a
       quit event it is	impossible for the user	to close the window. On	the
       other hand, if you do accept a quit event, the application window will
       be closed, and screen updates will still	report success,	even though
       the application will no longer be visible.

       Note:
	   The macro SDL_QuitRequested will return non-zero if a quit event is
	   pending.

       Returns:
	   true	if the event was handled, false	if it was not. If the event
	   wasn't handled, it will be handed over to the generic HandleEvent()
	   method.

   bool	SDLmm::EventHandler::HandleResizeEvent (int w, int h) [inline,
       virtual]
       Window resize event callback.

       This is used when an event of type SDL_VIDEORESIZE is reported.

       When SDL_RESIZABLE is passed as a flag to Display::SetVideoMode() the
       user is allowed to resize the applications window. When the window is
       resized an SDL_VIDEORESIZE is reported, with the	new window width and
       height values stored in w and h,	respectively. When an SDL_VIDEORESIZE
       is recieved the window should be	resized	to the new dimensions using
       Display::SetVideoMode();

       Parameters:

       w, h   new width	and height of the window.

       Returns:
	   true	if the event was handled, false	if it was not. If the event
	   wasn't handled, it will be handed over to the generic HandleEvent()
	   method.

   bool	SDLmm::EventHandler::HandleSysWMEvent () [inline, virtual]
       Platform-dependent window manager event callback.

       The system window manager event contains	a pointer to system-specific
       information about unknown window	manager	events.	If you enable this
       event using Event::EventState(),	it will	be generated whenever
       unhandled events	are received from the window manager. This can be
       used, for example, to implement cut-and-paste in	your application.

       If you want to obtain system-specific information about the window
       manager,	you can	fill the version member	of a SDL_SysWMinfo structure
       (details	can be found in	SDL_syswm.h, which must	be included) using the
       SDL_VERSION() macro found in SDL_version.h, and pass it to the
       function:

	     int SDL_GetWMInfo(SDL_SysWMinfo *info);

       Returns:
	   true	if the event was handled, false	if it was not. If the event
	   wasn't handled, it will be handed over to the generic HandleEvent()
	   method.

   bool	SDLmm::EventHandler::HandleUserEvent (Uint8 type, int code, void *
       data1, void * data2) [inline, virtual]
       This event is unique - it is never created by SDL but only by the user.
       The event can be	pushed onto the	event queue using Event::Push(). The
       contents	of data1 and data2 are completely up to	the programmer.	The
       only requirement	is that	type is	a value	from SDL_USEREVENT to
       SDL_NUMEVENTS-1 (inclusive).

       Parameters:

       type   SDL_USEREVENT through to SDL_NUMEVENTS-1

       code   user defined event code

       data1, data2
	      user defined data	pointers

       Returns:
	   true	if the event was handled, false	if it was not. If the event
	   wasn't handled, it will be handed over to the generic HandleEvent()
	   method.

AUTHOR
       Generated automatically by Doxygen for SDLmm from the source code.

SDLmm				  16 Jul 2001		SDLmm::EventHandler(3)

NAME | SYNOPSIS | DETAILED DESCRIPTION | MEMBER FUNCTION DOCUMENTATION | AUTHOR

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