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#include <gdk/gdk.h> union GdkEvent; struct GdkEventAny; struct GdkEventKey; struct GdkEventButton; struct GdkEventMotion; struct GdkEventExpose; struct GdkEventVisibility; struct GdkEventCrossing; struct GdkEventFocus; struct GdkEventConfigure; struct GdkEventProperty; struct GdkEventSelection; struct GdkEventDND; struct GdkEventProximity; struct GdkEventClient; struct GdkEventNoExpose; enum GdkVisibilityState; enum GdkCrossingMode; enum GdkNotifyType; enum GdkPropertyState; |
The event structs contain data specific to each type of event in GDK.
Note: 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().
union GdkEvent { GdkEventType type; GdkEventAny any; GdkEventExpose expose; GdkEventNoExpose no_expose; GdkEventVisibility visibility; GdkEventMotion motion; GdkEventButton button; GdkEventKey key; GdkEventCrossing crossing; GdkEventFocus focus_change; GdkEventConfigure configure; GdkEventProperty property; GdkEventSelection selection; GdkEventProximity proximity; GdkEventClient client; GdkEventDND dnd; }; |
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:
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:
or:struct GdkEventAny { GdkEventType type; GdkWindow *window; gint8 send_event; }; |
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.
GdkEventType type | the type of the event. |
GdkWindow *window | the window which received the event. |
gint8 send_event | TRUE if the event was sent explicitly (e.g. using XSendEvent). |
struct GdkEventKey { GdkEventType type; GdkWindow *window; gint8 send_event; guint32 time; guint state; guint keyval; gint length; gchar *string; }; |
Describes a key press or key release event.
GdkEventType type | the type of the event (GDK_KEY_PRESS or GDK_KEY_RELEASE). |
GdkWindow *window | the window which received the event. |
gint8 send_event | TRUE if the event was sent explicitly (e.g. using XSendEvent). |
guint32 time | the time of the event in milliseconds. |
guint state | a bit-mask representing the state of the modifier keys (e.g. Control, Shift and Alt) and the pointer buttons. See GdkModifierType. |
guint keyval | the key that was pressed or released. See the <gdk/gdkkeysym.h> header file for a complete list of GDK key codes. |
gint length | the length of string. |
gchar *string | a null-terminated multi-byte string containing the composed characters resulting from the key press. When text is being input, in a GtkEntry for example, it is these characters which should be added to the input buffer. When using Input Methods to support internationalized text input, the composed characters appear here after the pre-editing has been completed. |
struct GdkEventButton { GdkEventType type; GdkWindow *window; gint8 send_event; guint32 time; gdouble x; gdouble y; gdouble pressure; gdouble xtilt; gdouble ytilt; guint state; guint button; GdkInputSource source; guint32 deviceid; gdouble x_root, y_root; }; |
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:
GDK_BUTTON_PRESS
GDK_BUTTON_RELEASE
GDK_BUTTON_PRESS
GDK_2BUTTON_PRESS
GDK_BUTTON_RELEASE
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:
GDK_BUTTON_PRESS
GDK_BUTTON_RELEASE
GDK_BUTTON_PRESS
GDK_2BUTTON_PRESS
GDK_BUTTON_RELEASE
GDK_BUTTON_PRESS
GDK_3BUTTON_PRESS
GDK_BUTTON_RELEASE
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.
GdkEventType type | the type of the event (GDK_BUTTON_PRESS, GDK_2BUTTON_PRESS, GDK_3BUTTON_PRESS or GDK_BUTTON_RELEASE). |
GdkWindow *window | the window which received the event. |
gint8 send_event | TRUE if the event was sent explicitly (e.g. using XSendEvent). |
guint32 time | the time of the event in milliseconds. |
gdouble x | the x coordinate of the mouse relative to the window. |
gdouble y | the y coordinate of the mouse relative to the window. |
gdouble pressure | the pressure of the button press, intended for input devices such as graphics tablets. It defaults to 0.5. |
gdouble xtilt | the horizontal tilt of the input device. Defaults to 0. |
gdouble ytilt | the vertical tilt of the input device. Defaults to 0. |
guint state | a bit-mask representing the state of the modifier keys (e.g. Control, Shift and Alt) and the pointer buttons. See GdkModifierType. |
guint 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. |
GdkInputSource source | the input device where the event came from, usually GDK_SOURCE_MOUSE. |
guint32 deviceid | the input device ID, usually GDK_CORE_POINTER but may be different if touch screens or graphics tablets are being used. |
gdouble x_root | the x coordinate of the mouse relative to the root of the screen. |
gdouble y_root | the y coordinate of the mouse relative to the root of the screen. |
struct GdkEventMotion { GdkEventType type; GdkWindow *window; gint8 send_event; guint32 time; gdouble x; gdouble y; gdouble pressure; gdouble xtilt; gdouble ytilt; guint state; gint16 is_hint; GdkInputSource source; guint32 deviceid; gdouble x_root, y_root; }; |
GdkEventType type | the type of the event. |
GdkWindow *window | the window which received the event. |
gint8 send_event | TRUE if the event was sent explicitly (e.g. using XSendEvent). |
guint32 time | |
gdouble x | |
gdouble y | |
gdouble pressure | |
gdouble xtilt | |
gdouble ytilt | |
guint state | |
gint16 is_hint | |
GdkInputSource source | |
guint32 deviceid | |
gdouble x_root | |
gdouble y_root |
struct GdkEventExpose { GdkEventType type; GdkWindow *window; gint8 send_event; GdkRectangle area; gint count; /* If non-zero, how many more events follow. */ }; |
Generated when all or part of a window becomes visible and needs to be redrawn.
GdkEventType type | the type of the event (GDK_EXPOSE). |
GdkWindow *window | the window which received the event. |
gint8 send_event | TRUE if the event was sent explicitly (e.g. using XSendEvent). |
GdkRectangle area | the area that needs to be redrawn. |
gint 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. |
struct GdkEventVisibility { GdkEventType type; GdkWindow *window; gint8 send_event; GdkVisibilityState state; }; |
Generated when the window visibility status has changed.
GdkEventType type | the type of the event (GDK_VISIBILITY_NOTIFY). |
GdkWindow *window | the window which received the event. |
gint8 send_event | TRUE if the event was sent explicitly (e.g. using XSendEvent). |
GdkVisibilityState state | the new visibility state (GDK_VISIBILITY_FULLY_OBSCURED, GDK_VISIBILITY_PARTIAL or GDK_VISIBILITY_UNOBSCURED). |
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; }; |
GdkEventType type | the type of the event. |
GdkWindow *window | the window which received the event. |
gint8 send_event | TRUE if the event was sent explicitly (e.g. using XSendEvent). |
GdkWindow *subwindow | |
guint32 time | the time of the event in milliseconds. |
gdouble x | |
gdouble y | |
gdouble x_root | |
gdouble y_root | |
GdkCrossingMode mode | |
GdkNotifyType detail | |
gboolean focus | |
guint state |
struct GdkEventFocus { GdkEventType type; GdkWindow *window; gint8 send_event; gint16 in; }; |
Describes a change of keyboard focus.
GdkEventType type | the type of the event (GDK_FOCUS_CHANGE). |
GdkWindow *window | the window which received the event. |
gint8 send_event | TRUE if the event was sent explicitly (e.g. using XSendEvent). |
gint16 in | TRUE if the window has gained the keyboard focus, FALSE if it has lost the focus. |
struct GdkEventConfigure { GdkEventType type; GdkWindow *window; gint8 send_event; gint16 x, y; gint16 width; gint16 height; }; |
Generated when a window size or position has changed.
GdkEventType type | the type of the event (GDK_CONFIGURE). |
GdkWindow *window | the window which received the event. |
gint8 send_event | TRUE if the event was sent explicitly (e.g. using XSendEvent). |
gint16 x | the new x coordinate of the window, relative to its parent. |
gint16 y | the new y coordinate of the window, relative to its parent. |
gint16 width | the new width of the window. |
gint16 height | the new height of the window. |
struct GdkEventProperty { GdkEventType type; GdkWindow *window; gint8 send_event; GdkAtom atom; guint32 time; guint state; }; |
Describes a property change on a window.
GdkEventType type | the type of the event (GDK_PROPERTY_NOTIFY). |
GdkWindow *window | the window which received the event. |
gint8 send_event | TRUE if the event was sent explicitly (e.g. using XSendEvent). |
GdkAtom atom | the property that was changed. |
guint32 time | the time of the event in milliseconds. |
guint state | whether the property was changed (GDK_PROPERTY_NEW_VALUE) or deleted (GDK_PROPERTY_DELETE). |
struct GdkEventSelection { GdkEventType type; GdkWindow *window; gint8 send_event; GdkAtom selection; GdkAtom target; GdkAtom property; guint32 requestor; guint32 time; }; |
struct GdkEventDND { GdkEventType type; GdkWindow *window; gint8 send_event; GdkDragContext *context; guint32 time; gshort x_root, y_root; }; |
GdkEventType type | the type of the event. |
GdkWindow *window | the window which received the event. |
gint8 send_event | TRUE if the event was sent explicitly (e.g. using XSendEvent). |
GdkDragContext *context | |
guint32 time | the time of the event in milliseconds. |
gshort x_root | |
gshort y_root |
struct GdkEventProximity { GdkEventType type; GdkWindow *window; gint8 send_event; guint32 time; GdkInputSource source; guint32 deviceid; }; |
GdkEventType type | the type of the event. |
GdkWindow *window | the window which received the event. |
gint8 send_event | TRUE if the event was sent explicitly (e.g. using XSendEvent). |
guint32 time | the time of the event in milliseconds. |
GdkInputSource source | |
guint32 deviceid |
struct GdkEventClient { GdkEventType type; GdkWindow *window; gint8 send_event; GdkAtom message_type; gushort data_format; union { char b[20]; short s[10]; long l[5]; } data; }; |
An event sent by another client application.
GdkEventType type | the type of the event (GDK_CLIENT_EVENT). |
GdkWindow *window | the window which received the event. |
gint8 send_event | TRUE if the event was sent explicitly (e.g. using XSendEvent). |
GdkAtom message_type | the type of the message, which can be defined by the application. |
gushort data_format | the format of the data, given as the number of bits in each data element, i.e. 8, 16, or 32. 8-bit data uses the b array of the data union, 16-bit data uses the s array, and 32-bit data uses the l array. |
struct GdkEventNoExpose { GdkEventType type; GdkWindow *window; gint8 send_event; /* XXX: does anyone need the X major_code or minor_code fields? */ }; |
Generated when the area of a GdkDrawable being copied, with gdk_draw_pixmap() or gdk_window_copy_area(), was completely available.
FIXME: add more here.
GdkEventType type | the type of the event (GDK_NO_EXPOSE). |
GdkWindow *window | the window which received the event. |
gint8 send_event | TRUE if the event was sent explicitly (e.g. using XSendEvent). |
typedef enum { GDK_VISIBILITY_UNOBSCURED, GDK_VISIBILITY_PARTIAL, GDK_VISIBILITY_FULLY_OBSCURED } GdkVisibilityState; |
Specifies the visiblity status of a window for a GdkEventVisibility.
typedef enum { GDK_CROSSING_NORMAL, GDK_CROSSING_GRAB, GDK_CROSSING_UNGRAB } GdkCrossingMode; |
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; |
typedef enum { GDK_PROPERTY_NEW_VALUE, GDK_PROPERTY_DELETE } GdkPropertyState; |
Specifies the type of a property change for a GdkEventProperty.