racket/collects/scribblings/gui/mouse-event-class.scrbl
2010-11-05 15:54:41 -06:00

323 lines
8.6 KiB
Racket

#lang scribble/doc
@(require "common.ss")
@defclass/title[mouse-event% event% ()]{
A @scheme[mouse-event%] object encapsulates a mouse event.
Mouse events are primarily processed by
@xmethod[window<%> on-subwindow-event] and
@xmethod[canvas<%> on-event].
See also @|mousekeydiscuss|.
@defconstructor[([event-type (or/c 'enter 'leave 'left-down 'left-up
'middle-down 'middle-up
'right-down 'right-up 'motion)]
[left-down any/c #f]
[middle-down any/c #f]
[right-down any/c #f]
[x exact-integer? 0]
[y exact-integer? 0]
[shift-down any/c #f]
[control-down any/c #f]
[meta-down any/c #f]
[alt-down any/c #f]
[time-stamp exact-integer? 0]
[caps-down any/c #f])]{
Creates a mouse event for a particular type of event. The event types
are:
@itemize[
@item{@scheme['enter] --- mouse pointer entered the window}
@item{@scheme['leave] --- mouse pointer left the window}
@item{@scheme['left-down] --- left mouse button pressed}
@item{@scheme['left-up] --- left mouse button released}
@item{@scheme['middle-down] --- middle mouse button pressed}
@item{@scheme['middle-up] --- middle mouse button released}
@item{@scheme['right-down] --- right mouse button pressed (Mac OS X: click with control key pressed)}
@item{@scheme['right-up] --- right mouse button released (Mac OS X: release with control key pressed)}
@item{@scheme['motion] --- mouse moved, with or without button(s) pressed}
]
See the corresponding @schemeidfont{get-} and @schemeidfont{set-}
methods for information about @scheme[left-down],
@scheme[middle-down], @scheme[right-down], @scheme[x], @scheme[y],
@scheme[shift-down], @scheme[control-down], @scheme[meta-down],
@scheme[alt-down], @scheme[time-stamp], and @scheme[caps-down].
}
@defmethod[(button-changed? [button (or/c 'left 'middle 'right 'any) 'any])
boolean?]{
Returns @scheme[#t] if this was a mouse button press or release event,
@scheme[#f] otherwise. See also
@method[mouse-event% button-up?] and
@method[mouse-event% button-down?].
If @scheme[button] is not @scheme['any], then @scheme[#t] is only returned
if it is a release event for a specific button.
}
@defmethod[(button-down? [button (or/c 'left 'middle 'right 'any) 'any])
boolean?]{
Returns @scheme[#t] if the event is for a button press, @scheme[#f]
otherwise.
If @scheme[button] is not @scheme['any], then @scheme[#t] is only returned
if it is a press event for a specific button.
}
@defmethod[(button-up? [button (or/c 'left 'middle 'right 'any) 'any])
boolean?]{
Returns @scheme[#t] if the event is for a button release, @scheme[#f]
otherwise. (As noted in @|mousekeydiscuss|, button release events are
sometimes dropped.)
If @scheme[button] is not @scheme['any], then @scheme[#t] is only returned
if it is a release event for a specific button.
}
@defmethod[(dragging?)
boolean?]{
Returns @scheme[#t] if this was a dragging event (motion while a button
is pressed), @scheme[#f] otherwise.
}
@defmethod[(entering?)
boolean?]{
Returns @scheme[#t] if this event is for the mouse entering a window,
@scheme[#f] otherwise.
When the mouse button is up, an enter/leave event notifies a window
that it will start/stop receiving mouse events. When the mouse button
is down, however, the window receiving the mouse-down event receives
all mouse events until the button is released; enter/leave events are
not sent to other windows, and are not reliably delivered to the
click-handling window (since the window can detect movement out of
its region via @method[mouse-event% get-x] and @method[mouse-event%
get-y]). See also @|mousekeydiscuss|.
}
@defmethod[(get-alt-down)
boolean?]{
Returns @scheme[#t] if the Option (Mac OS X) key was down for the
event. When the Alt key is pressed in Windows, it is reported as a
Meta press (see @method[mouse-event% get-meta-down]).
}
@defmethod[(get-caps-down)
boolean?]{
Returns @scheme[#t] if the Caps Lock key was on for the event.
}
@defmethod[(get-control-down)
boolean?]{
Returns @scheme[#t] if the Control key was down for the event.
Under Mac OS X, if a control-key press is combined with a mouse button
click, the event is reported as a right-button click and
@method[mouse-event% get-control-down] for the event reports
@scheme[#f].
}
@defmethod[(get-event-type)
(or/c 'enter 'leave 'left-down 'left-up
'middle-down 'middle-up
'right-down 'right-up 'motion)]{
Returns the type of the event; see @scheme[mouse-event%] for
information about each event type. See also @method[mouse-event%
set-event-type].
}
@defmethod[(get-left-down)
boolean?]{
Returns @scheme[#t] if the left mouse button was down (but not pressed) during the event.
}
@defmethod[(get-meta-down)
boolean?]{
Returns @scheme[#t] if the Meta (X), Alt (Windows), or Command (Mac OS
X) key was down for the event.
}
@defmethod[(get-middle-down)
boolean?]{
Returns @scheme[#t] if the middle mouse button was down (but not
pressed) for the event. Under Mac OS X, a middle-button click is
impossible.
}
@defmethod[(get-right-down)
boolean?]{
Returns @scheme[#t] if the right mouse button was down (but not
pressed) for the event. Under Mac OS X, a control-click combination
is treated as a right-button click.
}
@defmethod[(get-shift-down)
boolean?]{
Returns @scheme[#t] if the Shift key was down for the event.
}
@defmethod[(get-x)
exact-integer?]{
Returns the x-position of the mouse at the time of the event, in the
target's window's (client-area) coordinate system.
}
@defmethod[(get-y)
exact-integer?]{
Returns the y-position of the mouse at the time of the event in the
target's window's (client-area) coordinate system.
}
@defmethod[(leaving?)
boolean?]{
Returns @scheme[#t] if this event is for the mouse leaving a window,
@scheme[#f] otherwise.
See @method[mouse-event% entering?] for information about enter and
leave events while the mouse button is clicked.
}
@defmethod[(moving?)
boolean?]{
Returns @scheme[#t] if this was a moving event (whether a button is
pressed is not), @scheme[#f] otherwise.
}
@defmethod[(set-alt-down [down? any/c])
void?]{
Sets whether the Option (Mac OS X) key was down for the event. When
the Alt key is pressed in Windows, it is reported as a Meta press
(see @method[mouse-event% set-meta-down]).
}
@defmethod[(set-caps-down [down? any/c])
void?]{
Sets whether the Caps Lock key was on for the event.
}
@defmethod[(set-control-down [down? any/c])
void?]{
Sets whether the Control key was down for the event.
Under Mac OS X, if a control-key press is combined with a mouse button
click, the event is reported as a right-button click and
@method[mouse-event% get-control-down] for the event reports
@scheme[#f].
}
@defmethod[(set-event-type [event-type (or/c 'enter 'leave 'left-down 'left-up
'middle-down 'middle-up
'right-down 'right-up 'motion)])
void?]{
Sets the type of the event; see @scheme[mouse-event%] for information
about each event type. See also @method[mouse-event% get-event-type].
}
@defmethod[(set-left-down [down? any/c])
void?]{
Sets whether the left mouse button was down (but not pressed) during
the event.
}
@defmethod[(set-meta-down [down? any/c])
void?]{
Sets whether the Meta (X), Alt (Windows), or Command (Mac OS X) key
was down for the event.
}
@defmethod[(set-middle-down [down? any/c])
void?]{
Sets whether the middle mouse button was down (but not pressed) for
the event. Under Mac OS X, a middle-button click is impossible.
}
@defmethod[(set-right-down [down? any/c])
void?]{
Sets whether the right mouse button was down (but not pressed) for the
event. Under Mac OS X, a control-click combination by the user is
treated as a right-button click.
}
@defmethod[(set-shift-down [down? any/c])
void?]{
Sets whether the Shift key was down for the event.
}
@defmethod[(set-x [pos exact-integer?])
void?]{
Sets the x-position of the mouse at the time of the event in the
target's window's (client-area) coordinate system.
}
@defmethod[(set-y [pos exact-integer?])
void?]{
Sets the y-position of the mouse at the time of the event in the
target's window's (client-area) coordinate system.
}}