| Line 12... |
Line 12... |
| 12 |
\description{
|
12 |
\description{
|
| 13 |
This function waits for input from a graphics window in the
|
13 |
This function waits for input from a graphics window in the
|
| 14 |
form of a mouse or keyboard event.
|
14 |
form of a mouse or keyboard event.
|
| 15 |
}
|
15 |
}
|
| 16 |
\usage{
|
16 |
\usage{
|
| 17 |
getGraphicsEvent(prompt = "Waiting for input",
|
17 |
getGraphicsEvent(prompt = "Waiting for input",
|
| 18 |
onMouseDown = NULL, onMouseMove = NULL,
|
18 |
onMouseDown = NULL, onMouseMove = NULL,
|
| 19 |
onMouseUp = NULL, onKeybd = NULL,
|
19 |
onMouseUp = NULL, onKeybd = NULL,
|
| 20 |
consolePrompt = prompt)
|
20 |
consolePrompt = prompt)
|
| 21 |
setGraphicsEventHandlers(which = dev.cur(), ...)
|
21 |
setGraphicsEventHandlers(which = dev.cur(), ...)
|
| 22 |
getGraphicsEventEnv(which = dev.cur())
|
22 |
getGraphicsEventEnv(which = dev.cur())
|
| Line 42... |
Line 42... |
| 42 |
|
42 |
|
| 43 |
The functions are related as follows. If any of the first five
|
43 |
The functions are related as follows. If any of the first five
|
| 44 |
arguments to \code{getGraphicsEvent} are given, then it uses those
|
44 |
arguments to \code{getGraphicsEvent} are given, then it uses those
|
| 45 |
in a call to \code{setGraphicsEventHandlers} to replace any existing
|
45 |
in a call to \code{setGraphicsEventHandlers} to replace any existing
|
| 46 |
handlers in the current device. This is for compatibility with pre-2.12.0 \R{}
|
46 |
handlers in the current device. This is for compatibility with pre-2.12.0 \R{}
|
| 47 |
versions. The current normal way to set up event handlers is to
|
47 |
versions. The current normal way to set up event handlers is to
|
| 48 |
set them using \code{setGraphicsEventHandlers} or \code{setGraphicsEventEnv} on
|
48 |
set them using \code{setGraphicsEventHandlers} or \code{setGraphicsEventEnv} on
|
| 49 |
one or more graphics devices, and then use \code{getGraphicsEvent()} with
|
49 |
one or more graphics devices, and then use \code{getGraphicsEvent()} with
|
| 50 |
no arguments to retrieve event data.
|
50 |
no arguments to retrieve event data.
|
| 51 |
\code{getGraphicsEventEnv()} may be used to save the event environment
|
51 |
\code{getGraphicsEventEnv()} may be used to save the event environment
|
| 52 |
for use later.
|
52 |
for use later.
|
| 53 |
|
53 |
|
| 54 |
The names of the arguments in \code{getGraphicsEvent} are special. When
|
54 |
The names of the arguments in \code{getGraphicsEvent} are special. When
|
| 55 |
handling events, the graphics system will look through the event
|
55 |
handling events, the graphics system will look through the event
|
| 56 |
environment for functions named \code{onMouseDown}, \code{onMouseMove}, \code{onMouseUp}
|
56 |
environment for functions named \code{onMouseDown}, \code{onMouseMove}, \code{onMouseUp}
|
| 57 |
and \code{onKeybd} and use them as event handlers. It will use
|
57 |
and \code{onKeybd} and use them as event handlers. It will use
|
| 58 |
\code{prompt} for a label on the graphics device. Two other special names are
|
58 |
\code{prompt} for a label on the graphics device. Two other special names are
|
| 59 |
\code{which}, which will identify the graphics device, and
|
59 |
\code{which}, which will identify the graphics device, and
|
| 60 |
\code{result}, where the result of the last event
|
60 |
\code{result}, where the result of the last event
|
| 61 |
handler will be stored before being returned by \code{getGraphicsEvent()}.
|
61 |
handler will be stored before being returned by \code{getGraphicsEvent()}.
|
| 62 |
|
62 |
|
| 63 |
The mouse event handlers should be functions with header
|
63 |
The mouse event handlers should be functions with header
|
| 64 |
\code{function(buttons, x, y)}. The coordinates \code{x}
|
64 |
\code{function(buttons, x, y)}. The coordinates \code{x}
|
| 65 |
and \code{y} will be passed to mouse event handlers in device independent
|
65 |
and \code{y} will be passed to mouse event handlers in device independent
|
| 66 |
coordinates (i.e. the lower left corner of the window is \code{(0,0)},
|
66 |
coordinates (i.e. the lower left corner of the window is \code{(0,0)},
|
| 67 |
the upper right is \code{(1,1)}). The \code{buttons} argument
|
67 |
the upper right is \code{(1,1)}). The \code{buttons} argument
|
| 68 |
will be a vector listing the buttons
|
68 |
will be a vector listing the buttons
|
| 69 |
that are pressed at the time of the event, with 0 for left, 1 for middle, and 2
|
69 |
that are pressed at the time of the event, with 0 for left, 1 for middle, and 2
|
| 70 |
for right.
|
70 |
for right.
|
| 71 |
|
71 |
|
| 72 |
The keyboard event handler should be a function with header
|
72 |
The keyboard event handler should be a function with header
|
| 73 |
\code{function(key)}. A single element character vector will be passed
|
73 |
\code{function(key)}. A single element character vector will be passed
|
| 74 |
to this handler, corresponding to the key press. Shift and other modifier
|
74 |
to this handler, corresponding to the key press. Shift and other modifier
|
| Line 81... |
Line 81... |
| 81 |
\item Edit keys, passed as one of \code{"Ins", "Del"}
|
81 |
\item Edit keys, passed as one of \code{"Ins", "Del"}
|
| 82 |
\item Function keys, passed as one of \code{"F1", "F2", ...}
|
82 |
\item Function keys, passed as one of \code{"F1", "F2", ...}
|
| 83 |
}
|
83 |
}
|
| 84 |
|
84 |
|
| 85 |
The event handlers are standard R functions, and will be executed as though called
|
85 |
The event handlers are standard R functions, and will be executed as though called
|
| 86 |
from the event environment.
|
86 |
from the event environment.
|
| 87 |
|
87 |
|
| 88 |
In an interactive session, events will be processed until
|
88 |
In an interactive session, events will be processed until
|
| 89 |
\itemize{
|
89 |
\itemize{
|
| 90 |
\item one of the event handlers returns
|
90 |
\item one of the event handlers returns
|
| 91 |
a non-\code{NULL} value which will be returned as the value of
|
91 |
a non-\code{NULL} value which will be returned as the value of
|
| 92 |
\code{getGraphicsEvent}, or
|
92 |
\code{getGraphicsEvent}, or
|
| 93 |
\item the user interrupts the function from the
|
93 |
\item the user interrupts the function from the
|
| 94 |
console.
|
94 |
console.
|
| 95 |
}
|
95 |
}
|
| 96 |
}
|
96 |
}
|
| 97 |
\value{
|
97 |
\value{
|
| 98 |
When run interactively,
|
98 |
When run interactively,
|
| 99 |
\code{getGraphicsEvent} returns a non-\code{NULL} value returned from one of the event handlers.
|
99 |
\code{getGraphicsEvent} returns a non-\code{NULL} value returned from one of the event handlers.
|
| 100 |
In a non-interactive session, \code{getGraphicsEvent} will return \code{NULL} immediately.
|
100 |
In a non-interactive session, \code{getGraphicsEvent} will return \code{NULL} immediately.
|
| 101 |
|
101 |
|
| 102 |
\code{getGraphicsEventEnv} returns the current event environment for the graphics device,
|
102 |
\code{getGraphicsEventEnv} returns the current event environment for the graphics device,
|
| 103 |
or \code{NULL} if none has been set.
|
103 |
or \code{NULL} if none has been set.
|
| Line 115... |
Line 115... |
| 115 |
starty <- NULL
|
115 |
starty <- NULL
|
| 116 |
usr <- NULL
|
116 |
usr <- NULL
|
| 117 |
|
117 |
|
| 118 |
devset <- function()
|
118 |
devset <- function()
|
| 119 |
if (dev.cur() != eventEnv$which) dev.set(eventEnv$which)
|
119 |
if (dev.cur() != eventEnv$which) dev.set(eventEnv$which)
|
| 120 |
|
120 |
|
| 121 |
dragmousedown <- function(buttons, x, y) {
|
121 |
dragmousedown <- function(buttons, x, y) {
|
| 122 |
startx <<- x
|
122 |
startx <<- x
|
| 123 |
starty <<- y
|
123 |
starty <<- y
|
| 124 |
devset()
|
124 |
devset()
|
| 125 |
usr <<- par("usr")
|
125 |
usr <<- par("usr")
|
| 126 |
eventEnv$onMouseMove <- dragmousemove
|
126 |
eventEnv$onMouseMove <- dragmousemove
|
| 127 |
NULL
|
127 |
NULL
|
| 128 |
}
|
128 |
}
|
| 129 |
|
129 |
|
| 130 |
dragmousemove <- function(buttons, x, y) {
|
130 |
dragmousemove <- function(buttons, x, y) {
|
| 131 |
devset()
|
131 |
devset()
|
| 132 |
deltax <- diff(grconvertX(c(startx, x), "ndc", "user"))
|
132 |
deltax <- diff(grconvertX(c(startx, x), "ndc", "user"))
|
| 133 |
deltay <- diff(grconvertY(c(starty, y), "ndc", "user"))
|
133 |
deltay <- diff(grconvertY(c(starty, y), "ndc", "user"))
|
| 134 |
plot(..., xlim = usr[1:2]-deltax, xaxs = "i",
|
134 |
plot(..., xlim = usr[1:2]-deltax, xaxs = "i",
|
| 135 |
ylim = usr[3:4]-deltay, yaxs = "i")
|
135 |
ylim = usr[3:4]-deltay, yaxs = "i")
|
| 136 |
NULL
|
136 |
NULL
|
| 137 |
}
|
137 |
}
|
| 138 |
|
138 |
|
| 139 |
mouseup <- function(buttons, x, y) {
|
139 |
mouseup <- function(buttons, x, y) {
|
| 140 |
eventEnv$onMouseMove <- NULL
|
140 |
eventEnv$onMouseMove <- NULL
|
| 141 |
}
|
141 |
}
|
| 142 |
|
142 |
|
| 143 |
keydown <- function(key) {
|
143 |
keydown <- function(key) {
|
| 144 |
if (key == "q") return(invisible(1))
|
144 |
if (key == "q") return(invisible(1))
|
| 145 |
eventEnv$onMouseMove <- NULL
|
145 |
eventEnv$onMouseMove <- NULL
|
| 146 |
NULL
|
146 |
NULL
|
| 147 |
}
|
147 |
}
|
| 148 |
|
148 |
|
| 149 |
setGraphicsEventHandlers(prompt = "Click and drag, hit q to quit",
|
149 |
setGraphicsEventHandlers(prompt = "Click and drag, hit q to quit",
|
| 150 |
onMouseDown = dragmousedown,
|
150 |
onMouseDown = dragmousedown,
|
| 151 |
onMouseUp = mouseup,
|
151 |
onMouseUp = mouseup,
|
| 152 |
onKeybd = keydown)
|
152 |
onKeybd = keydown)
|
| 153 |
eventEnv <- getGraphicsEventEnv()
|
153 |
eventEnv <- getGraphicsEventEnv()
|
The R Project SVN
R