1.55.2 Instance variables

event <- buttons: mask=int

Bitmask containing various status information on the event. It is not advised to rely on the contents of the bitmask as this might change in the future.

The status of the modifier keys is normally tested using event->has_modifier. The type of click (single, double, triple) is requested using event<-multiclick and the button for button-related events using event<-button.

Current definition of the mask-values

control-key		0x1
shift-key		0x2
meta-key		0x4
left-button		0x8
middle-button	0x10
right-button	0x20

single-click	0x40
double-click	0x80
triple-click	0xC0

event <- id: event_id

Identifier for the event. This is either a name occurring in the event-type hierarchy @event_tree or an integer. The latter is used for ASCII-type events and represents the ASCII value. See also event<-key.

Whether or not an event is of specified type is normally tested using event->is_a. Other useful classifications are realised using event->is_up, event->is_down, event->is_drag, event->has_modifier, event<-click_time and event<-click_displacement.

One event requires special treatment. This is the event related to wheel-mice, mice normally having two buttons and a scroll-wheel. Rotations of the scroll-wheel are mapped to an event object with event<-id: wheel. Conform the Microsoft windows conventions, this event is has a rotation attribute, associate using object->attribute. The rotation has the value 120 if the wheel is rotated from the user and -120 when rotated towards the user.

In the X11 version, wheel-events are normally mapped to the virtual mouse-buttons 4 and 5. If the class-variable event.x11_wheel_mouse = @on (default in the X11 version), the low-level event handling will map the button 4 and button 5 events to wheel events.

The wheel event is handled by class window, class editor, class list_browser and class scroll_bar.

See also

event->is_a

event-position: point*

This slot is initially @nil. It is filled when the event position is computed through event<-position or event<-area_position. Subsequent calls to one of these methods will update the point<-x and point<-y values and return the same point object.

See also

- event<-position
- event<-area_position

event <- receiver: graphical|frame

Object the graphical is currently posted to by event->post. Note that this graphical is not necessarily the object that initialy received the event. See also event<-window.

See also

- event-window
- event->post

event-time: alien:Time

Timestamp of the event in milliseconds since this PCE process was initialised. Used infrequently. See also event<-multiclick.

event <- window: window|frame

Window from which the event was generated. See also device->event.

See also

- event-y
- event-x
- event-receiver

event <- x: pixels=int

X-coordinate of the event relative to event<-window. Note that this position is not in the window's coordinate system, but relative to the top-left corner of the X-widget realising the window.

See also

- event-window
- event-y

event <- y: pixels=int

Y-coordinate of the event relative to event<-window. See event<-x for details.

See also

- event-window
- event-x