Events

enum GdkEventType

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_NO_EXPOSE		= 30
} GdkEventType;

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.

enum GdkEventMask

typedef enum
{
  GDK_EXPOSURE_MASK		= 1 << 1,
  GDK_POINTER_MOTION_MASK	= 1 << 2,
  GDK_POINTER_MOTION_HINT_MASK	= 1 << 3,
  GDK_BUTTON_MOTION_MASK	= 1 << 4,
  GDK_BUTTON1_MOTION_MASK	= 1 << 5,
  GDK_BUTTON2_MOTION_MASK	= 1 << 6,
  GDK_BUTTON3_MOTION_MASK	= 1 << 7,
  GDK_BUTTON_PRESS_MASK		= 1 << 8,
  GDK_BUTTON_RELEASE_MASK	= 1 << 9,
  GDK_KEY_PRESS_MASK		= 1 << 10,
  GDK_KEY_RELEASE_MASK		= 1 << 11,
  GDK_ENTER_NOTIFY_MASK		= 1 << 12,
  GDK_LEAVE_NOTIFY_MASK		= 1 << 13,
  GDK_FOCUS_CHANGE_MASK		= 1 << 14,
  GDK_STRUCTURE_MASK		= 1 << 15,
  GDK_PROPERTY_CHANGE_MASK	= 1 << 16,
  GDK_VISIBILITY_NOTIFY_MASK	= 1 << 17,
  GDK_PROXIMITY_IN_MASK		= 1 << 18,
  GDK_PROXIMITY_OUT_MASK	= 1 << 19,
  GDK_SUBSTRUCTURE_MASK		= 1 << 20,
  GDK_ALL_EVENTS_MASK		= 0x0FFFFF
} GdkEventMask;

A set of bit-flags to indicate which events a window is to receive. Most of these masks map onto one or more of the GdkEventType event types above.

GDK_POINTER_MOTION_HINT_MASK is a special mask which is used to reduce the number of GDK_MOTION_NOTIFY events received. Normally a GDK_MOTION_NOTIFY event is received each time the mouse moves. However, if the application spends a lot of time processing the event (updating the display, for example), it can easily lag behind the position of the mouse. When using the GDK_POINTER_MOTION_HINT_MASK the server will only send GDK_MOTION_NOTIFY events when the application asks for them, by calling gdk_window_get_pointer().

GDK_CURRENT_TIME

#define GDK_CURRENT_TIME     0L

Represents the current time, and can be used anywhere a time is expected.

GDK_PRIORITY_EVENTS

#define	  GDK_PRIORITY_EVENTS		(G_PRIORITY_DEFAULT)

This is the priority that events from the X server are given in the GLib Main Loop.

gdk_events_pending ()

gboolean    gdk_events_pending              (void);

Checks if any events are waiting to be processed.

gdk_event_peek ()

GdkEvent*   gdk_event_peek                  (void);

Gets a copy of the first GdkEvent in the event queue. (Note that this function will not get more events from the X server. It only checks the events that have already been moved to the GDK event queue.)

gdk_event_get ()

GdkEvent*   gdk_event_get                   (void);

Gets the next GdkEvent to be processed, fetching events from the X server if necessary.

gdk_event_get_graphics_expose ()

GdkEvent*   gdk_event_get_graphics_expose   (GdkWindow *window);

Waits for a GraphicsExpose or NoExpose event from the X server. This is used in the GtkText and GtkCList widgets in GTK+ to make sure any GraphicsExpose events are handled before the widget is scrolled.

gdk_event_put ()

void        gdk_event_put                   (GdkEvent *event);

Appends a copy of the given event onto the front of the event queue.

gdk_event_copy ()

GdkEvent*   gdk_event_copy                  (GdkEvent *event);

Copies a GdkEvent, copying or incrementing the reference count of the resources associated with it (e.g. GdkWindow's and strings).

gdk_event_free ()

void        gdk_event_free                  (GdkEvent *event);

Frees a GdkEvent, freeing or decrementing any resources associated with it. Note that this function should only be called with events returned from gdk_event_peek(), gdk_event_get(), gdk_event_get_graphics_expose() and gdk_event_copy().

gdk_event_get_time ()

guint32     gdk_event_get_time              (GdkEvent *event);

Gets the timestamp from a GdkEvent.

gdk_event_handler_set ()

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

Sets the function to call to handle all events from GDK.

Note that GTK+ uses this to install its own event handler, so it is probably not useful for GTK+ applications.

GdkEventFunc ()

void        (*GdkEventFunc)                 (GdkEvent *event,
                                             gpointer data);

Specifies the type of function passed to gdk_event_handler_set() to handle all GDK events.

gdk_event_send_client_message ()

gboolean    gdk_event_send_client_message   (GdkEvent *event,
                                             guint32 xid);

Sends an X ClientMessage event to a given window.

This could be used for communicating between different applications, though the amount of data is limited to 20 bytes.

gdk_event_send_clientmessage_toall ()

void        gdk_event_send_clientmessage_toall
                                            (GdkEvent *event);

Sends an X ClientMessage event to all toplevel windows.

Toplevel windows are determined by checking for the WM_STATE property, as described in the Inter-Client Communication Conventions Manual (ICCCM). If no windows are found with the WM_STATE property set, the message is sent to all children of the root window.

gdk_add_client_message_filter ()

void        gdk_add_client_message_filter   (GdkAtom message_type,
                                             GdkFilterFunc func,
                                             gpointer data);

Adds a filter to be called when X ClientMessage events are received.

gdk_get_show_events ()

gint        gdk_get_show_events             (void);

Returns non-zero if event debugging output is enabled.

gdk_set_show_events ()

void        gdk_set_show_events             (gint show_events);

Sets whether event debugging information is output. Note that GTK+ must be compiled with debugging enabled, i.e. using the '--enable-debug' configure option.