gtk/gdk/gdkevents.h

/* GDK - The GIMP Drawing Kit
 * Copyright (C) 1995-1997 Peter Mattis, Spencer Kimball and Josh MacDonald
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the
 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
 * Boston, MA 02111-1307, USA.
 */

/*
 * Modified by the GTK+ Team and others 1997-2000.  See the AUTHORS
 * file for a list of people on the GTK+ Team.  See the ChangeLog
 * files for a list of changes.  These files are distributed with
 * GTK+ at ftp://ftp.gtk.org/pub/gtk/.
 */

#if !defined (__GDK_H_INSIDE__) && !defined (GDK_COMPILATION)
#error "Only <gdk/gdk.h> can be included directly."
#endif

#ifndef __GDK_EVENTS_H__
#define __GDK_EVENTS_H__

#include <gdk/gdkcolor.h>
#include <gdk/gdktypes.h>
#include <gdk/gdkdnd.h>
#include <gdk/gdkdevice.h>

G_BEGIN_DECLS


/**
 * SECTION:event_structs
 * @Short_description: Data structures specific to each type of event
 * @Title: Event Structures
 *
 * The event structs contain data specific to each type of event in GDK.
 *
 * <note>
 * <para>
 * A common mistake is to forget to set the event mask of a widget so that
 * the required events are received. See gtk_widget_set_events().
 * </para>
 * </note>
 */


#define GDK_TYPE_EVENT          (gdk_event_get_type ())

/**
 * GDK_PRIORITY_EVENTS:
 *
 * This is the priority that events from the X server are given in the
 * <link linkend="glib-The-Main-Event-Loop">GLib Main Loop</link>.
 */
#define GDK_PRIORITY_EVENTS	(G_PRIORITY_DEFAULT)

/**
 * GDK_PRIORITY_REDRAW:
 *
 * This is the priority that the idle handler processing window updates
 * is given in the
 * <link linkend="glib-The-Main-Event-Loop">GLib Main Loop</link>.
 */
#define GDK_PRIORITY_REDRAW     (G_PRIORITY_HIGH_IDLE + 20)


typedef struct _GdkEventAny	    GdkEventAny;
typedef struct _GdkEventExpose	    GdkEventExpose;
typedef struct _GdkEventVisibility  GdkEventVisibility;
typedef struct _GdkEventMotion	    GdkEventMotion;
typedef struct _GdkEventButton	    GdkEventButton;
typedef struct _GdkEventScroll      GdkEventScroll;  
typedef struct _GdkEventKey	    GdkEventKey;
typedef struct _GdkEventFocus	    GdkEventFocus;
typedef struct _GdkEventCrossing    GdkEventCrossing;
typedef struct _GdkEventConfigure   GdkEventConfigure;
typedef struct _GdkEventProperty    GdkEventProperty;
typedef struct _GdkEventSelection   GdkEventSelection;
typedef struct _GdkEventOwnerChange GdkEventOwnerChange;
typedef struct _GdkEventProximity   GdkEventProximity;
typedef struct _GdkEventDND         GdkEventDND;
typedef struct _GdkEventWindowState GdkEventWindowState;
typedef struct _GdkEventSetting     GdkEventSetting;
typedef struct _GdkEventGrabBroken  GdkEventGrabBroken;

typedef union  _GdkEvent	    GdkEvent;

/**
 * GdkEventFunc:
 * @event: the #GdkEvent to process.
 * @data: (closure): user data set when the event handler was installed with
 *   gdk_event_handler_set().
 *
 * Specifies the type of function passed to gdk_event_handler_set() to
 * handle all GDK events.
 */
typedef void (*GdkEventFunc) (GdkEvent *event,
			      gpointer	data);

/* Event filtering */

/**
 * GdkXEvent:
 *
 * Used to represent native events (<type>XEvent</type>s for the X11
 * backend, <type>MSG</type>s for Win32).
 */
typedef void GdkXEvent;	  /* Can be cast to window system specific
			   * even type, XEvent on X11, MSG on Win32.
			   */

/**
 * GdkFilterReturn:
 * @GDK_FILTER_CONTINUE: event not handled, continue processing.
 * @GDK_FILTER_TRANSLATE: native event translated into a GDK event and stored
 *  in the <literal>event</literal> structure that was passed in.
 * @GDK_FILTER_REMOVE: event handled, terminate processing.
 *
 * Specifies the result of applying a #GdkFilterFunc to a native event.
 */
typedef enum {
  GDK_FILTER_CONTINUE,	  /* Event not handled, continue processesing */
  GDK_FILTER_TRANSLATE,	  /* Native event translated into a GDK event and
                             stored in the "event" structure that was
                             passed in */
  GDK_FILTER_REMOVE	  /* Terminate processing, removing event */
} GdkFilterReturn;

/**
 * GdkFilterFunc:
 * @xevent: the native event to filter.
 * @event: the GDK event to which the X event will be translated.
 * @data: user data set when the filter was installed.
 *
 * Specifies the type of function used to filter native events before they are
 * converted to GDK events.
 *
 * When a filter is called, @event is unpopulated, except for
 * <literal>event->window</literal>. The filter may translate the native
 * event to a GDK event and store the result in @event, or handle it without
 * translation. If the filter translates the event and processing should
 * continue, it should return %GDK_FILTER_TRANSLATE.
 *
 * Returns: a #GdkFilterReturn value.
 */
typedef GdkFilterReturn (*GdkFilterFunc) (GdkXEvent *xevent,
					  GdkEvent *event,
					  gpointer  data);


/**
 * GdkEventType:
 * @GDK_NOTHING: a special code to indicate a null event.
 * @GDK_DELETE: the window manager has requested that the toplevel window be
 *   hidden or destroyed, usually when the user clicks on a special icon in the
 *   title bar.
 * @GDK_DESTROY: the window has been destroyed.
 * @GDK_EXPOSE: all or part of the window has become visible and needs to be
 *   redrawn.
 * @GDK_MOTION_NOTIFY: the pointer (usually a mouse) has moved.
 * @GDK_BUTTON_PRESS: a mouse button has been pressed.
 * @GDK_2BUTTON_PRESS: a mouse button has been double-clicked (clicked twice
 *   within a short period of time). Note that each click also generates a
 *   %GDK_BUTTON_PRESS event.
 * @GDK_3BUTTON_PRESS: a mouse button has been clicked 3 times in a short period
 *   of time. Note that each click also generates a %GDK_BUTTON_PRESS event.
 * @GDK_BUTTON_RELEASE: a mouse button has been released.
 * @GDK_KEY_PRESS: a key has been pressed.
 * @GDK_KEY_RELEASE: a key has been released.
 * @GDK_ENTER_NOTIFY: the pointer has entered the window.
 * @GDK_LEAVE_NOTIFY: the pointer has left the window.
 * @GDK_FOCUS_CHANGE: the keyboard focus has entered or left the window.
 * @GDK_CONFIGURE: the size, position or stacking order of the window has changed.
 *   Note that GTK+ discards these events for %GDK_WINDOW_CHILD windows.
 * @GDK_MAP: the window has been mapped.
 * @GDK_UNMAP: the window has been unmapped.
 * @GDK_PROPERTY_NOTIFY: a property on the window has been changed or deleted.
 * @GDK_SELECTION_CLEAR: the application has lost ownership of a selection.
 * @GDK_SELECTION_REQUEST: another application has requested a selection.
 * @GDK_SELECTION_NOTIFY: a selection has been received.
 * @GDK_PROXIMITY_IN: an input device has moved into contact with a sensing
 *   surface (e.g. a touchscreen or graphics tablet).
 * @GDK_PROXIMITY_OUT: an input device has moved out of contact with a sensing
 *   surface.
 * @GDK_DRAG_ENTER: the mouse has entered the window while a drag is in progress.
 * @GDK_DRAG_LEAVE: the mouse has left the window while a drag is in progress.
 * @GDK_DRAG_MOTION: the mouse has moved in the window while a drag is in
 *   progress.
 * @GDK_DRAG_STATUS: the status of the drag operation initiated by the window
 *   has changed.
 * @GDK_DROP_START: a drop operation onto the window has started.
 * @GDK_DROP_FINISHED: the drop operation initiated by the window has completed.
 * @GDK_CLIENT_EVENT: a message has been received from another application.
 * @GDK_VISIBILITY_NOTIFY: the window visibility status has changed.
 * @GDK_SCROLL: the scroll wheel was turned
 * @GDK_WINDOW_STATE: the state of a window has changed. See #GdkWindowState
 *   for the possible window states
 * @GDK_SETTING: a setting has been modified.
 * @GDK_OWNER_CHANGE: the owner of a selection has changed. This event type
 *   was added in 2.6
 * @GDK_GRAB_BROKEN: a pointer or keyboard grab was broken. This event type
 *   was added in 2.8.
 * @GDK_DAMAGE: the content of the window has been changed. This event type
 *   was added in 2.14.
 * @GDK_EVENT_LAST: marks the end of the GdkEventType enumeration. Added in 2.18
 *
 * Specifies the type of the event.
 *
 * Do not confuse these events with the signals that GTK+ widgets emit.
 * Although many of these events result in corresponding signals being emitted,
 * the events are often transformed or filtered along the way.
 */
typedef enum
{
  GDK_NOTHING		= -1,
  GDK_DELETE		= 0,
  GDK_DESTROY		= 1,
  GDK_EXPOSE		= 2,
  GDK_MOTION_NOTIFY	= 3,
  GDK_BUTTON_PRESS	= 4,
  GDK_2BUTTON_PRESS	= 5,
  GDK_3BUTTON_PRESS	= 6,
  GDK_BUTTON_RELEASE	= 7,
  GDK_KEY_PRESS		= 8,
  GDK_KEY_RELEASE	= 9,
  GDK_ENTER_NOTIFY	= 10,
  GDK_LEAVE_NOTIFY	= 11,
  GDK_FOCUS_CHANGE	= 12,
  GDK_CONFIGURE		= 13,
  GDK_MAP		= 14,
  GDK_UNMAP		= 15,
  GDK_PROPERTY_NOTIFY	= 16,
  GDK_SELECTION_CLEAR	= 17,
  GDK_SELECTION_REQUEST = 18,
  GDK_SELECTION_NOTIFY	= 19,
  GDK_PROXIMITY_IN	= 20,
  GDK_PROXIMITY_OUT	= 21,
  GDK_DRAG_ENTER        = 22,
  GDK_DRAG_LEAVE        = 23,
  GDK_DRAG_MOTION       = 24,
  GDK_DRAG_STATUS       = 25,
  GDK_DROP_START        = 26,
  GDK_DROP_FINISHED     = 27,
  GDK_CLIENT_EVENT	= 28,
  GDK_VISIBILITY_NOTIFY = 29,
  GDK_SCROLL            = 31,
  GDK_WINDOW_STATE      = 32,
  GDK_SETTING           = 33,
  GDK_OWNER_CHANGE      = 34,
  GDK_GRAB_BROKEN       = 35,
  GDK_DAMAGE            = 36,
  GDK_EVENT_LAST        /* helper variable for decls */
} GdkEventType;

/**
 * GdkVisibilityState:
 * @GDK_VISIBILITY_UNOBSCURED: the window is completely visible.
 * @GDK_VISIBILITY_PARTIAL: the window is partially visible.
 * @GDK_VISIBILITY_FULLY_OBSCURED: the window is not visible at all.
 *
 * Specifies the visiblity status of a window for a #GdkEventVisibility.
 */
typedef enum
{
  GDK_VISIBILITY_UNOBSCURED,
  GDK_VISIBILITY_PARTIAL,
  GDK_VISIBILITY_FULLY_OBSCURED
} GdkVisibilityState;

/**
 * GdkScrollDirection:
 * @GDK_SCROLL_UP: the window is scrolled up.
 * @GDK_SCROLL_DOWN: the window is scrolled down.
 * @GDK_SCROLL_LEFT: the window is scrolled to the left.
 * @GDK_SCROLL_RIGHT: the window is scrolled to the right.
 *
 * Specifies the direction for #GdkEventScroll.
 */
typedef enum
{
  GDK_SCROLL_UP,
  GDK_SCROLL_DOWN,
  GDK_SCROLL_LEFT,
  GDK_SCROLL_RIGHT
} GdkScrollDirection;

/**
 * GdkNotifyType:
 * @GDK_NOTIFY_ANCESTOR: the window is entered from an ancestor or
 *   left towards an ancestor.
 * @GDK_NOTIFY_VIRTUAL: the pointer moves between an ancestor and an
 *   inferior of the window.
 * @GDK_NOTIFY_INFERIOR: the window is entered from an inferior or
 *   left towards an inferior.
 * @GDK_NOTIFY_NONLINEAR: the window is entered from or left towards
 *   a window which is neither an ancestor nor an inferior.
 * @GDK_NOTIFY_NONLINEAR_VIRTUAL: the pointer moves between two windows
 *   which are not ancestors of each other and the window is part of
 *   the ancestor chain between one of these windows and their least
 *   common ancestor.
 * @GDK_NOTIFY_UNKNOWN: an unknown type of enter/leave event occurred.
 *
 * Specifies the kind of crossing for #GdkEventCrossing.
 *
 * See the X11 protocol specification of <type>LeaveNotify</type> for
 * full details of crossing event generation.
 */
typedef enum
{
  GDK_NOTIFY_ANCESTOR		= 0,
  GDK_NOTIFY_VIRTUAL		= 1,
  GDK_NOTIFY_INFERIOR		= 2,
  GDK_NOTIFY_NONLINEAR		= 3,
  GDK_NOTIFY_NONLINEAR_VIRTUAL	= 4,
  GDK_NOTIFY_UNKNOWN		= 5
} GdkNotifyType;

/**
 * GdkCrossingMode:
 * @GDK_CROSSING_NORMAL: crossing because of pointer motion.
 * @GDK_CROSSING_GRAB: crossing because a grab is activated.
 * @GDK_CROSSING_UNGRAB: crossing because a grab is deactivated.
 * @GDK_CROSSING_GTK_GRAB: crossing because a GTK+ grab is activated.
 * @GDK_CROSSING_GTK_UNGRAB: crossing because a GTK+ grab is deactivated.
 * @GDK_CROSSING_STATE_CHANGED: crossing because a GTK+ widget changed
 *   state (e.g. sensitivity).
 *
 * Specifies the crossing mode for #GdkEventCrossing.
 */
typedef enum
{
  GDK_CROSSING_NORMAL,
  GDK_CROSSING_GRAB,
  GDK_CROSSING_UNGRAB,
  GDK_CROSSING_GTK_GRAB,
  GDK_CROSSING_GTK_UNGRAB,
  GDK_CROSSING_STATE_CHANGED
} GdkCrossingMode;

/**
 * GdkPropertyState:
 * @GDK_PROPERTY_NEW_VALUE: the property value was changed.
 * @GDK_PROPERTY_DELETE: the property was deleted.
 *
 * Specifies the type of a property change for a #GdkEventProperty.
 */
typedef enum
{
  GDK_PROPERTY_NEW_VALUE,
  GDK_PROPERTY_DELETE
} GdkPropertyState;

/**
 * GdkWindowState:
 * @GDK_WINDOW_STATE_WITHDRAWN: the window is not shown.
 * @GDK_WINDOW_STATE_ICONIFIED: the window is minimized.
 * @GDK_WINDOW_STATE_MAXIMIZED: the window is maximized.
 * @GDK_WINDOW_STATE_STICKY: the window is sticky.
 * @GDK_WINDOW_STATE_FULLSCREEN: the window is maximized without
 *   decorations.
 * @GDK_WINDOW_STATE_ABOVE: the window is kept above other windows.
 * @GDK_WINDOW_STATE_BELOW: the window is kept below other windows.
 *
 * Specifies the state of a toplevel window.
 */
typedef enum
{
  GDK_WINDOW_STATE_WITHDRAWN  = 1 << 0,
  GDK_WINDOW_STATE_ICONIFIED  = 1 << 1,
  GDK_WINDOW_STATE_MAXIMIZED  = 1 << 2,
  GDK_WINDOW_STATE_STICKY     = 1 << 3,
  GDK_WINDOW_STATE_FULLSCREEN = 1 << 4,
  GDK_WINDOW_STATE_ABOVE      = 1 << 5,
  GDK_WINDOW_STATE_BELOW      = 1 << 6
} GdkWindowState;

/**
 * GdkSettingAction:
 * @GDK_SETTING_ACTION_NEW: a setting was added.
 * @GDK_SETTING_ACTION_CHANGED: a setting was changed.
 * @GDK_SETTING_ACTION_DELETED: a setting was deleted.
 *
 * Specifies the kind of modification applied to a setting in a
 * #GdkEventSetting.
 */
typedef enum
{
  GDK_SETTING_ACTION_NEW,
  GDK_SETTING_ACTION_CHANGED,
  GDK_SETTING_ACTION_DELETED
} GdkSettingAction;

/**
 * GdkOwnerChange:
 * @GDK_OWNER_CHANGE_NEW_OWNER: some other app claimed the ownership
 * @GDK_OWNER_CHANGE_DESTROY: the window was destroyed
 * @GDK_OWNER_CHANGE_CLOSE: the client was closed
 *
 * Specifies why a selection ownership was changed.
 */
typedef enum
{
  GDK_OWNER_CHANGE_NEW_OWNER,
  GDK_OWNER_CHANGE_DESTROY,
  GDK_OWNER_CHANGE_CLOSE
} GdkOwnerChange;

/**
 * GdkEventAny:
 * @type: the type of the event.
 * @window: the window which received the event.
 * @send_event: %TRUE if the event was sent explicitly (e.g. using
 *   <function>XSendEvent</function>).
 *
 * Contains the fields which are common to all event structs.
 * Any event pointer can safely be cast to a pointer to a #GdkEventAny to
 * access these fields.
 */
struct _GdkEventAny
{
  GdkEventType type;
  GdkWindow *window;
  gint8 send_event;
};

/**
 * GdkEventExpose:
 * @type: the type of the event (%GDK_EXPOSE or %GDK_DAMAGE).
 * @window: the window which received the event.
 * @send_event: %TRUE if the event was sent explicitly (e.g. using
 *   <function>XSendEvent</function>).
 * @area: bounding box of @region.
 * @region: the region that needs to be redrawn.
 * @count: the number of contiguous %GDK_EXPOSE events following this one.
 *   The only use for this is "exposure compression", i.e. handling all
 *   contiguous %GDK_EXPOSE events in one go, though GDK performs some
 *   exposure compression so this is not normally needed.
 *
 * Generated when all or part of a window becomes visible and needs to be
 * redrawn.
 */
struct _GdkEventExpose
{
  GdkEventType type;
  GdkWindow *window;
  gint8 send_event;
  GdkRectangle area;
  cairo_region_t *region;
  gint count; /* If non-zero, how many more events follow. */
};

/**
 * GdkEventVisibility:
 * @type: the type of the event (%GDK_VISIBILITY_NOTIFY).
 * @window: the window which received the event.
 * @send_event: %TRUE if the event was sent explicitly (e.g. using
 *   <function>XSendEvent</function>).
 * @state: the new visibility state (%GDK_VISIBILITY_FULLY_OBSCURED,
 *   %GDK_VISIBILITY_PARTIAL or %GDK_VISIBILITY_UNOBSCURED).
 *
 * Generated when the window visibility status has changed.
 */
struct _GdkEventVisibility
{
  GdkEventType type;
  GdkWindow *window;
  gint8 send_event;
  GdkVisibilityState state;
};

/**
 * GdkEventMotion:
 * @type: the type of the event.
 * @window: the window which received the event.
 * @send_event: %TRUE if the event was sent explicitly (e.g. using
 *   <function>XSendEvent</function>).
 * @time: the time of the event in milliseconds.
 * @x: the x coordinate of the pointer relative to the window.
 * @y: the y coordinate of the pointer relative to the window.
 * @axes: @x, @y translated to the axes of @device, or %NULL if @device is
 *   the mouse.
 * @state: (type GdkModifierType): a bit-mask representing the state of
 *   the modifier keys (e.g. Control, Shift and Alt) and the pointer
 *   buttons. See #GdkModifierType.
 * @is_hint: set to 1 if this event is just a hint, see the
 *   %GDK_POINTER_MOTION_HINT_MASK value of #GdkEventMask.
 * @device: the device where the event originated.
 * @x_root: the x coordinate of the pointer relative to the root of the
 *   screen.
 * @y_root: the y coordinate of the pointer relative to the root of the
 *   screen.
 *
 * Generated when the pointer moves.
 */
struct _GdkEventMotion
{
  GdkEventType type;
  GdkWindow *window;
  gint8 send_event;
  guint32 time;
  gdouble x;
  gdouble y;
  gdouble *axes;
  guint state;
  gint16 is_hint;
  GdkDevice *device;
  gdouble x_root, y_root;
};

/**
 * GdkEventButton:
 * @type: the type of the event (%GDK_BUTTON_PRESS, %GDK_2BUTTON_PRESS,
 *   %GDK_3BUTTON_PRESS or %GDK_BUTTON_RELEASE).
 * @window: the window which received the event.
 * @send_event: %TRUE if the event was sent explicitly (e.g. using
 *   <function>XSendEvent</function>).
 * @time: the time of the event in milliseconds.
 * @x: the x coordinate of the pointer relative to the window.
 * @y: the y coordinate of the pointer relative to the window.
 * @axes: @x, @y translated to the axes of @device, or %NULL if @device is
 *   the mouse.
 * @state: (type GdkModifierType): a bit-mask representing the state of
 *   the modifier keys (e.g. Control, Shift and Alt) and the pointer
 *   buttons. See #GdkModifierType.
 * @button: the button which was pressed or released, numbered from 1 to 5.
 *   Normally button 1 is the left mouse button, 2 is the middle button,
 *   and 3 is the right button. On 2-button mice, the middle button can
 *   often be simulated by pressing both mouse buttons together.
 * @device: the device where the event originated.
 * @x_root: the x coordinate of the pointer relative to the root of the
 *   screen.
 * @y_root: the y coordinate of the pointer relative to the root of the
 *   screen.
 *
 * Used for button press and button release events. The
 * @type field will be one of %GDK_BUTTON_PRESS,
 * %GDK_2BUTTON_PRESS, %GDK_3BUTTON_PRESS, and %GDK_BUTTON_RELEASE.
 *
 * Double and triple-clicks result in a sequence of events being received.
 * For double-clicks the order of events will be:
 * <orderedlist>
 * <listitem><para>%GDK_BUTTON_PRESS</para></listitem>
 * <listitem><para>%GDK_BUTTON_RELEASE</para></listitem>
 * <listitem><para>%GDK_BUTTON_PRESS</para></listitem>
 * <listitem><para>%GDK_2BUTTON_PRESS</para></listitem>
 * <listitem><para>%GDK_BUTTON_RELEASE</para></listitem>
 * </orderedlist>
 * Note that the first click is received just like a normal
 * button press, while the second click results in a %GDK_2BUTTON_PRESS
 * being received just after the %GDK_BUTTON_PRESS.
 *
 * Triple-clicks are very similar to double-clicks, except that
 * %GDK_3BUTTON_PRESS is inserted after the third click. The order of the
 * events is:
 * <orderedlist>
 * <listitem><para>%GDK_BUTTON_PRESS</para></listitem>
 * <listitem><para>%GDK_BUTTON_RELEASE</para></listitem>
 * <listitem><para>%GDK_BUTTON_PRESS</para></listitem>
 * <listitem><para>%GDK_2BUTTON_PRESS</para></listitem>
 * <listitem><para>%GDK_BUTTON_RELEASE</para></listitem>
 * <listitem><para>%GDK_BUTTON_PRESS</para></listitem>
 * <listitem><para>%GDK_3BUTTON_PRESS</para></listitem>
 * <listitem><para>%GDK_BUTTON_RELEASE</para></listitem>
 * </orderedlist>
 *
 * For a double click to occur, the second button press must occur within
 * 1/4 of a second of the first. For a triple click to occur, the third
 * button press must also occur within 1/2 second of the first button press.
 */
struct _GdkEventButton
{
  GdkEventType type;
  GdkWindow *window;
  gint8 send_event;
  guint32 time;
  gdouble x;
  gdouble y;
  gdouble *axes;
  guint state;
  guint button;
  GdkDevice *device;
  gdouble x_root, y_root;
};

/**
 * GdkEventScroll:
 * @type: the type of the event (%GDK_SCROLL).
 * @window: the window which received the event.
 * @send_event: %TRUE if the event was sent explicitly (e.g. using
 *   <function>XSendEvent</function>).
 * @time: the time of the event in milliseconds.
 * @x: the x coordinate of the pointer relative to the window.
 * @y: the y coordinate of the pointer relative to the window.
 * @state: (type GdkModifierType): a bit-mask representing the state of
 *   the modifier keys (e.g. Control, Shift and Alt) and the pointer
 *   buttons. See #GdkModifierType.
 * @direction: the direction to scroll to (one of %GDK_SCROLL_UP,
 *   %GDK_SCROLL_DOWN, %GDK_SCROLL_LEFT and %GDK_SCROLL_RIGHT).
 * @device: the device where the event originated.
 * @x_root: the x coordinate of the pointer relative to the root of the
 *   screen.
 * @y_root: the y coordinate of the pointer relative to the root of the
 *   screen.
 *
 * Generated from button presses for the buttons 4 to 7. Wheel mice are
 * usually configured to generate button press events for buttons 4 and 5
 * when the wheel is turned.
 */
struct _GdkEventScroll
{
  GdkEventType type;
  GdkWindow *window;
  gint8 send_event;
  guint32 time;
  gdouble x;
  gdouble y;
  guint state;
  GdkScrollDirection direction;
  GdkDevice *device;
  gdouble x_root, y_root;
};

/**
 * GdkEventKey:
 * @type: the type of the event (%GDK_KEY_PRESS or %GDK_KEY_RELEASE).
 * @window: the window which received the event.
 * @send_event: %TRUE if the event was sent explicitly (e.g. using
 *   <function>XSendEvent</function>).
 * @time: the time of the event in milliseconds.
 * @state: (type GdkModifierType): a bit-mask representing the state of
 *   the modifier keys (e.g. Control, Shift and Alt) and the pointer
 *   buttons. See #GdkModifierType.
 * @keyval: the key that was pressed or released. See the
 *   <filename>&lt;gdk/gdkkeysyms.h&gt;</filename> header file for a
 *   complete list of GDK key codes.
 * @length: the length of @string.
 * @string: a string containing the an approximation of the text that
 *   would result from this keypress. The only correct way to handle text
 *   input of text is using input methods (see #GtkIMContext), so this
 *   field is deprecated and should never be used.
 *   (gdk_unicode_to_keyval() provides a non-deprecated way of getting
 *   an approximate translation for a key.) The string is encoded in the
 *   encoding of the current locale (Note: this for backwards compatibility:
 *   strings in GTK+ and GDK are typically in UTF-8.) and NUL-terminated.
 *   In some cases, the translation of the key code will be a single
 *   NUL byte, in which case looking at @length is necessary to distinguish
 *   it from the an empty translation.
 * @hardware_keycode: the raw code of the key that was pressed or released.
 * @group: the keyboard group.
 * @is_modifier: a flag that indicates if @hardware_keycode is mapped to a
 *   modifier. Since 2.10
 *
 * Describes a key press or key release event.
 */
struct _GdkEventKey
{
  GdkEventType type;
  GdkWindow *window;
  gint8 send_event;
  guint32 time;
  guint state;
  guint keyval;
  gint length;
  gchar *string;
  guint16 hardware_keycode;
  guint8 group;
  guint is_modifier : 1;
};

/**
 * GdkEventCrossing:
 * @type: the type of the event (%GDK_ENTER_NOTIFY or %GDK_LEAVE_NOTIFY).
 * @window: the window which received the event.
 * @send_event: %TRUE if the event was sent explicitly (e.g. using
 *  <function>XSendEvent</function>).
 * @subwindow: the window that was entered or left.
 * @time: the time of the event in milliseconds.
 * @x: the x coordinate of the pointer relative to the window.
 * @y: the y coordinate of the pointer relative to the window.
 * @x_root: the x coordinate of the pointer relative to the root of the screen.
 * @y_root: the y coordinate of the pointer relative to the root of the screen.
 * @mode: the crossing mode (%GDK_CROSSING_NORMAL, %GDK_CROSSING_GRAB,
 *  %GDK_CROSSING_UNGRAB, %GDK_CROSSING_GTK_GRAB, %GDK_CROSSING_GTK_UNGRAB or
 *  %GDK_CROSSING_STATE_CHANGED).  %GDK_CROSSING_GTK_GRAB, %GDK_CROSSING_GTK_UNGRAB,
 *  and %GDK_CROSSING_STATE_CHANGED were added in 2.14 and are always synthesized,
 *  never native.
 * @detail: the kind of crossing that happened (%GDK_NOTIFY_INFERIOR,
 *  %GDK_NOTIFY_ANCESTOR, %GDK_NOTIFY_VIRTUAL, %GDK_NOTIFY_NONLINEAR or
 *  %GDK_NOTIFY_NONLINEAR_VIRTUAL).
 * @focus: %TRUE if @window is the focus window or an inferior.
 * @state: (type GdkModifierType): a bit-mask representing the state of
 *   the modifier keys (e.g. Control, Shift and Alt) and the pointer
 *   buttons. See #GdkModifierType.
 *
 * Generated when the pointer enters or leaves a window.
 */
struct _GdkEventCrossing
{
  GdkEventType type;
  GdkWindow *window;
  gint8 send_event;
  GdkWindow *subwindow;
  guint32 time;
  gdouble x;
  gdouble y;
  gdouble x_root;
  gdouble y_root;
  GdkCrossingMode mode;
  GdkNotifyType detail;
  gboolean focus;
  guint state;
};

/**
 * GdkEventFocus:
 * @type: the type of the event (%GDK_FOCUS_CHANGE).
 * @window: the window which received the event.
 * @send_event: %TRUE if the event was sent explicitly (e.g. using
 *   <function>XSendEvent</function>).
 * @in: %TRUE if the window has gained the keyboard focus, %FALSE if
 *   it has lost the focus.
 *
 * Describes a change of keyboard focus.
 */
struct _GdkEventFocus
{
  GdkEventType type;
  GdkWindow *window;
  gint8 send_event;
  gint16 in;
};

/**
 * GdkEventConfigure:
 * @type: the type of the event (%GDK_CONFIGURE).
 * @window: the window which received the event.
 * @send_event: %TRUE if the event was sent explicitly (e.g. using
 *   <function>XSendEvent</function>).
 * @x: the new x coordinate of the window, relative to its parent.
 * @y: the new y coordinate of the window, relative to its parent.
 * @width: the new width of the window.
 * @height: the new height of the window.
 *
 * Generated when a window size or position has changed.
 */
struct _GdkEventConfigure
{
  GdkEventType type;
  GdkWindow *window;
  gint8 send_event;
  gint x, y;
  gint width;
  gint height;
};

/**
 * GdkEventProperty:
 * @type: the type of the event (%GDK_PROPERTY_NOTIFY).
 * @window: the window which received the event.
 * @send_event: %TRUE if the event was sent explicitly (e.g. using
 *   <function>XSendEvent</function>).
 * @atom: the property that was changed.
 * @time: the time of the event in milliseconds.
 * @state: whether the property was changed (%GDK_PROPERTY_NEW_VALUE) or
 *   deleted (%GDK_PROPERTY_DELETE).
 *
 * Describes a property change on a window.
 */
struct _GdkEventProperty
{
  GdkEventType type;
  GdkWindow *window;
  gint8 send_event;
  GdkAtom atom;
  guint32 time;
  guint state;
};

/**
 * GdkEventSelection:
 * @type: the type of the event (%GDK_SELECTION_CLEAR,
 *   %GDK_SELECTION_NOTIFY or %GDK_SELECTION_REQUEST).
 * @window: the window which received the event.
 * @send_event: %TRUE if the event was sent explicitly (e.g. using
 *   <function>XSendEvent</function>).
 * @selection: the selection.
 * @target: the target to which the selection should be converted.
 * @property: the property in which to place the result of the conversion.
 * @time: the time of the event in milliseconds.
 * @requestor: the window on which to place @property or %NULL if none.
 *
 * Generated when a selection is requested or ownership of a selection
 * is taken over by another client application.
 */
struct _GdkEventSelection
{
  GdkEventType type;
  GdkWindow *window;
  gint8 send_event;
  GdkAtom selection;
  GdkAtom target;
  GdkAtom property;
  guint32 time;
  GdkWindow *requestor;
};

/**
 * GdkEventOwnerChange:
 * @type: the type of the event (%GDK_OWNER_CHANGE).
 * @window: the window which received the event
 * @send_event: %TRUE if the event was sent explicitly (e.g. using
 *   <function>XSendEvent</function>)
 * @owner: the new owner of the selection, or %NULL if there is none
 * @reason: the reason for the ownership change as a #GdkOwnerChange value
 * @selection: the atom identifying the selection
 * @time: the timestamp of the event
 * @selection_time: the time at which the selection ownership was taken
 *   over
 *
 * Generated when the owner of a selection changes. On X11, this
 * information is only available if the X server supports the XFIXES
 * extension.
 *
 * Since: 2.6
 */
struct _GdkEventOwnerChange
{
  GdkEventType type;
  GdkWindow *window;
  gint8 send_event;
  GdkWindow *owner;
  GdkOwnerChange reason;
  GdkAtom selection;
  guint32 time;
  guint32 selection_time;
};

/**
 * GdkEventProximity:
 * @type: the type of the event (%GDK_PROXIMITY_IN or %GDK_PROXIMITY_OUT).
 * @window: the window which received the event.
 * @send_event: %TRUE if the event was sent explicitly (e.g. using <function>XSendEvent</function>).
 * @time: the time of the event in milliseconds.
 * @device: the device where the event originated.
 *
 * Proximity events are generated when using GDK's wrapper for the
 * XInput extension. The XInput extension is an add-on for standard X
 * that allows you to use nonstandard devices such as graphics tablets.
 * A proximity event indicates that the stylus has moved in or out of
 * contact with the tablet, or perhaps that the user's finger has moved
 * in or out of contact with a touch screen.
 *
 * This event type will be used pretty rarely. It only is important for
 * XInput aware programs that are drawing their own cursor.
 */
struct _GdkEventProximity
{
  GdkEventType type;
  GdkWindow *window;
  gint8 send_event;
  guint32 time;
  GdkDevice *device;
};

/**
 * GdkEventSetting:
 * @type: the type of the event (%GDK_SETTING).
 * @window: the window which received the event.
 * @send_event: %TRUE if the event was sent explicitly (e.g. using
 *   <function>XSendEvent</function>).
 * @action: what happened to the setting (%GDK_SETTING_ACTION_NEW,
 *   %GDK_SETTING_ACTION_CHANGED or %GDK_SETTING_ACTION_DELETED).
 * @name: the name of the setting.
 *
 * Generated when a setting is modified.
 */
struct _GdkEventSetting
{
  GdkEventType type;
  GdkWindow *window;
  gint8 send_event;
  GdkSettingAction action;
  char *name;
};

/**
 * GdkEventWindowState:
 * @type: the type of the event (%GDK_WINDOW_STATE).
 * @window: the window which received the event.
 * @send_event: %TRUE if the event was sent explicitly (e.g. using
 *   <function>XSendEvent</function>).
 * @changed_mask: mask specifying what flags have changed.
 * @new_window_state: the new window state, a combination of
 *   #GdkWindowState bits.
 *
 * Generated when the state of a toplevel window changes.
 */
struct _GdkEventWindowState
{
  GdkEventType type;
  GdkWindow *window;
  gint8 send_event;
  GdkWindowState changed_mask;
  GdkWindowState new_window_state;
};

/**
 * GdkEventGrabBroken:
 * @type: the type of the event (%GDK_GRAB_BROKEN)
 * @window: the window which received the event, i.e. the window
 *   that previously owned the grab
 * @send_event: %TRUE if the event was sent explicitly (e.g. using
 *   <function>XSendEvent</function>).
 * @keyboard: %TRUE if a keyboard grab was broken, %FALSE if a pointer
 *   grab was broken
 * @implicit: %TRUE if the broken grab was implicit
 * @grab_window: If this event is caused by another grab in the same
 *   application, @grab_window contains the new grab window. Otherwise
 *   @grab_window is %NULL.
 *
 * Generated when a pointer or keyboard grab is broken. On X11, this happens
 * when the grab window becomes unviewable (i.e. it or one of its ancestors
 * is unmapped), or if the same application grabs the pointer or keyboard
 * again. Note that implicit grabs (which are initiated by button presses)
 * can also cause #GdkEventGrabBroken events.
 *
 * Since: 2.8
 */
struct _GdkEventGrabBroken {
  GdkEventType type;
  GdkWindow *window;
  gint8 send_event;
  gboolean keyboard;
  gboolean implicit;
  GdkWindow *grab_window;
};

/**
 * GdkEventDND:
 * @type: the type of the event (%GDK_DRAG_ENTER, %GDK_DRAG_LEAVE,
 *   %GDK_DRAG_MOTION, %GDK_DRAG_STATUS, %GDK_DROP_START or
 *   %GDK_DROP_FINISHED).
 * @window: the window which received the event.
 * @send_event: %TRUE if the event was sent explicitly (e.g. using
 *   <function>XSendEvent</function>).
 * @context: the #GdkDragContext for the current DND operation.
 * @time: the time of the event in milliseconds.
 * @x_root: the x coordinate of the pointer relative to the root of the
 *   screen, only set for %GDK_DRAG_MOTION and %GDK_DROP_START.
 * @y_root: the y coordinate of the pointer relative to the root of the
 *   screen, only set for %GDK_DRAG_MOTION and %GDK_DROP_START.
 *
 * Generated during DND operations.
 */
struct _GdkEventDND {
  GdkEventType type;
  GdkWindow *window;
  gint8 send_event;
  GdkDragContext *context;

  guint32 time;
  gshort x_root, y_root;
};

/**
 * GdkEvent:
 *
 * The #GdkEvent struct contains a union of all of the event structs,
 * and allows access to the data fields in a number of ways.
 *
 * The event type is always the first field in all of the event structs, and
 * can always be accessed with the following code, no matter what type of
 * event it is:
 * <informalexample>
 * <programlisting>
 *   GdkEvent *event;
 *   GdkEventType type;
 *
 *   type = event->type;
 * </programlisting>
 * </informalexample>
 *
 * To access other fields of the event structs, the pointer to the event
 * can be cast to the appropriate event struct pointer, or the union member
 * name can be used. For example if the event type is %GDK_BUTTON_PRESS
 * then the x coordinate of the button press can be accessed with:
 * <informalexample>
 * <programlisting>
 *   GdkEvent *event;
 *   gdouble x;
 *
 *   x = ((GdkEventButton*)event)->x;
 * </programlisting>
 * </informalexample>
 * or:
 * <informalexample>
 * <programlisting>
 *   GdkEvent *event;
 *   gdouble x;
 *
 *   x = event->button.x;
 * </programlisting>
 * </informalexample>
 */
union _GdkEvent
{
  GdkEventType		    type;
  GdkEventAny		    any;
  GdkEventExpose	    expose;
  GdkEventVisibility	    visibility;
  GdkEventMotion	    motion;
  GdkEventButton	    button;
  GdkEventScroll            scroll;
  GdkEventKey		    key;
  GdkEventCrossing	    crossing;
  GdkEventFocus		    focus_change;
  GdkEventConfigure	    configure;
  GdkEventProperty	    property;
  GdkEventSelection	    selection;
  GdkEventOwnerChange  	    owner_change;
  GdkEventProximity	    proximity;
  GdkEventDND               dnd;
  GdkEventWindowState       window_state;
  GdkEventSetting           setting;
  GdkEventGrabBroken        grab_broken;
};

GType     gdk_event_get_type            (void) G_GNUC_CONST;

gboolean  gdk_events_pending	 	(void);
GdkEvent* gdk_event_get			(void);

GdkEvent* gdk_event_peek                (void);
void      gdk_event_put	 		(const GdkEvent *event);

GdkEvent* gdk_event_new                 (GdkEventType    type);
GdkEvent* gdk_event_copy     		(const GdkEvent *event);
void	  gdk_event_free     		(GdkEvent 	*event);

guint32   gdk_event_get_time            (const GdkEvent  *event);
gboolean  gdk_event_get_state           (const GdkEvent  *event,
                                         GdkModifierType *state);
gboolean  gdk_event_get_coords		(const GdkEvent  *event,
					 gdouble	 *x_win,
					 gdouble	 *y_win);
gboolean  gdk_event_get_root_coords	(const GdkEvent  *event,
					 gdouble	 *x_root,
					 gdouble	 *y_root);
gboolean  gdk_event_get_axis            (const GdkEvent  *event,
                                         GdkAxisUse       axis_use,
                                         gdouble         *value);
void       gdk_event_set_device         (GdkEvent        *event,
                                         GdkDevice       *device);
GdkDevice* gdk_event_get_device         (const GdkEvent  *event);
void       gdk_event_set_source_device  (GdkEvent        *event,
                                         GdkDevice       *device);
GdkDevice* gdk_event_get_source_device  (const GdkEvent  *event);
void      gdk_event_request_motions     (const GdkEventMotion *event);

gboolean  gdk_events_get_distance       (GdkEvent        *event1,
                                         GdkEvent        *event2,
                                         gdouble         *distance);
gboolean  gdk_events_get_angle          (GdkEvent        *event1,
                                         GdkEvent        *event2,
                                         gdouble         *angle);
gboolean  gdk_events_get_center         (GdkEvent        *event1,
                                         GdkEvent        *event2,
                                         gdouble         *x,
                                         gdouble         *y);

void	  gdk_event_handler_set 	(GdkEventFunc    func,
					 gpointer        data,
					 GDestroyNotify  notify);

void       gdk_event_set_screen         (GdkEvent        *event,
                                         GdkScreen       *screen);
GdkScreen *gdk_event_get_screen         (const GdkEvent  *event);

void	  gdk_set_show_events		(gboolean	 show_events);
gboolean  gdk_get_show_events		(void);

#ifndef GDK_MULTIHEAD_SAFE

gboolean gdk_setting_get                           (const gchar *name,
                                                    GValue          *value);

#endif /* GDK_MULTIHEAD_SAFE */

G_END_DECLS

#endif /* __GDK_EVENTS_H__ */