187 lines
8.0 KiB
Plaintext
187 lines
8.0 KiB
Plaintext
'\"
|
|
'\" Copyright (c) 1990-1994 The Regents of the University of California.
|
|
'\" Copyright (c) 1994-1996 Sun Microsystems, Inc.
|
|
'\"
|
|
'\" See the file "license.terms" for information on usage and redistribution
|
|
'\" of this file, and for a DISCLAIMER OF ALL WARRANTIES.
|
|
'\"
|
|
.TH selection n 8.1 Tk "Tk Built-In Commands"
|
|
.so man.macros
|
|
.BS
|
|
'\" Note: do not modify the .SH NAME line immediately below!
|
|
.SH NAME
|
|
selection \- Manipulate the X selection
|
|
.SH SYNOPSIS
|
|
\fBselection \fIoption\fR ?\fIarg arg ...\fR?
|
|
.BE
|
|
.SH DESCRIPTION
|
|
.PP
|
|
This command provides a Tcl interface to the X selection mechanism and
|
|
implements the full selection functionality described in the
|
|
X Inter-Client Communication Conventions Manual (ICCCM).
|
|
.PP
|
|
Note that for management of the \fBCLIPBOARD\fR selection (see below), the
|
|
\fBclipboard\fR command may also be used.
|
|
.PP
|
|
The first argument to \fBselection\fR determines the format of the
|
|
rest of the arguments and the behavior of the command. The following
|
|
forms are currently supported:
|
|
.TP
|
|
\fBselection clear\fR ?\fB\-displayof\fR \fIwindow\fR? ?\fB\-selection\fR \fIselection\fR?
|
|
.
|
|
If \fIselection\fR exists anywhere on \fIwindow\fR's display, clear it
|
|
so that no window owns the selection anymore. \fISelection\fR
|
|
specifies the X selection that should be cleared, and should be an
|
|
atom name such as \fBPRIMARY\fR or \fBCLIPBOARD\fR; see the Inter-Client
|
|
Communication Conventions Manual for complete details.
|
|
\fISelection\fR defaults to \fBPRIMARY\fR and \fIwindow\fR defaults to
|
|
.QW . .
|
|
Returns an empty string.
|
|
.TP
|
|
\fBselection get\fR ?\fB\-displayof\fR \fIwindow\fR? ?\fB\-selection\fR \fIselection\fR? ?\fB\-type\fR \fItype\fR?
|
|
.
|
|
Retrieves the value of \fIselection\fR from \fIwindow\fR's display and
|
|
returns it as a result. \fISelection\fR defaults to \fBPRIMARY\fR and
|
|
\fIwindow\fR defaults to
|
|
.QW . .
|
|
\fIType\fR specifies the form in which the selection is to be returned
|
|
(the desired
|
|
.QW target
|
|
for conversion, in ICCCM terminology), and
|
|
should be an atom name such as \fBSTRING\fR or \fBFILE_NAME\fR; see the
|
|
Inter-Client Communication Conventions Manual for complete details.
|
|
\fIType\fR defaults to \fBSTRING\fR. The selection owner may choose to
|
|
return the selection in any of several different representation
|
|
formats, such as \fBSTRING\fR, \fBUTF8_STRING\fR, \fBATOM\fR,
|
|
\fBINTEGER\fR, etc. (this format is different
|
|
than the selection type; see the ICCCM for all the confusing details).
|
|
If the selection is returned in a non-string format, such as \fBINTEGER\fR
|
|
or \fBATOM\fR, the \fBselection\fR command converts it to string format as a
|
|
collection of fields separated by spaces: atoms are converted to their
|
|
textual names, and anything else is converted to hexadecimal integers.
|
|
Note that \fBselection get\fR does not retrieve the selection in the
|
|
\fBUTF8_STRING\fR format unless told to.
|
|
.TP
|
|
\fBselection handle\fR ?\fB\-selection\fR \fIs\fR? ?\fB\-type\fR \fIt\fR? ?\fB\-format\fR \fIf\fR? \fIwindow command\fR
|
|
.
|
|
Creates a handler for selection requests, such that \fIcommand\fR will
|
|
be executed whenever selection \fIs\fR is owned by \fIwindow\fR and
|
|
someone attempts to retrieve it in the form given by type \fIt\fR
|
|
(e.g. \fIt\fR is specified in the \fBselection get\fR command).
|
|
\fIS\fR defaults to \fBPRIMARY\fR, \fIt\fR defaults to \fBSTRING\fR, and
|
|
\fIf\fR defaults to \fBSTRING\fR. If \fIcommand\fR is an empty string
|
|
then any existing handler for \fIwindow\fR, \fIt\fR, and
|
|
\fIs\fR is removed.
|
|
Note that when the selection is handled as type \fBSTRING\fR it is also
|
|
automatically handled as type \fBUTF8_STRING\fR as well.
|
|
.RS
|
|
.PP
|
|
When \fIselection\fR is requested, \fIwindow\fR is the selection owner,
|
|
and \fItype\fR is the requested type, \fIcommand\fR will be executed
|
|
as a Tcl command with two additional numbers appended to it
|
|
(with space separators).
|
|
The two additional numbers
|
|
are \fIoffset\fR and \fImaxChars\fR: \fIoffset\fR specifies a starting
|
|
character position in the selection and \fImaxChars\fR gives the maximum
|
|
number of characters to retrieve. The command should return a value consisting
|
|
of at most \fImaxChars\fR of the selection, starting at position
|
|
\fIoffset\fR. For very large selections (larger than \fImaxChars\fR)
|
|
the selection will be retrieved using several invocations of \fIcommand\fR
|
|
with increasing \fIoffset\fR values. If \fIcommand\fR returns a string
|
|
whose length is less than \fImaxChars\fR, the return value is assumed to
|
|
include all of the remainder of the selection; if the length of
|
|
\fIcommand\fR's result is equal to \fImaxChars\fR then
|
|
\fIcommand\fR will be invoked again, until it eventually
|
|
returns a result shorter than \fImaxChars\fR. The value of \fImaxChars\fR
|
|
will always be relatively large (thousands of characters).
|
|
.PP
|
|
If \fIcommand\fR returns an error then the selection retrieval is rejected
|
|
just as if the selection did not exist at all.
|
|
.PP
|
|
The \fIformat\fR argument specifies the representation that should be
|
|
used to transmit the selection to the requester (the second column of
|
|
Table 2 of the ICCCM), and defaults to \fBSTRING\fR. If \fIformat\fR is
|
|
\fBSTRING\fR, the selection is transmitted as 8-bit ASCII characters (i.e.
|
|
just in the form returned by \fIcommand\fR, in the system \fBencoding\fR;
|
|
the \fBUTF8_STRING\fR format always uses UTF-8 as its encoding).
|
|
If \fIformat\fR is
|
|
\fBATOM\fR, then the return value from \fIcommand\fR is divided into fields
|
|
separated by white space; each field is converted to its atom value,
|
|
and the 32-bit atom value is transmitted instead of the atom name.
|
|
For any other \fIformat\fR, the return value from \fIcommand\fR is
|
|
divided into fields separated by white space and each field is
|
|
converted to a 32-bit integer; an array of integers is transmitted
|
|
to the selection requester.
|
|
.PP
|
|
The \fIformat\fR argument is needed only for compatibility with
|
|
selection requesters that do not use Tk. If Tk is being
|
|
used to retrieve the selection then the value is converted back to
|
|
a string at the requesting end, so \fIformat\fR is
|
|
irrelevant.
|
|
.RE
|
|
.TP
|
|
\fBselection own\fR ?\fB\-displayof\fR \fIwindow\fR? ?\fB\-selection\fR \fIselection\fR?
|
|
.TP
|
|
\fBselection own\fR ?\fB\-command\fR \fIcommand\fR? ?\fB\-selection\fR \fIselection\fR? \fIwindow\fR
|
|
.
|
|
The first form of \fBselection own\fR returns the path name of the
|
|
window in this application that owns \fIselection\fR on the display
|
|
containing \fIwindow\fR, or an empty string if no window in this
|
|
application owns the selection. \fISelection\fR defaults to \fBPRIMARY\fR and
|
|
\fIwindow\fR defaults to
|
|
.QW . .
|
|
.RS
|
|
.PP
|
|
The second form of \fBselection own\fR causes \fIwindow\fR to become
|
|
the new owner of \fIselection\fR on \fIwindow\fR's display, returning
|
|
an empty string as result. The existing owner, if any, is notified
|
|
that it has lost the selection.
|
|
If \fIcommand\fR is specified, it is a Tcl script to execute when
|
|
some other window claims ownership of the selection away from
|
|
\fIwindow\fR. \fISelection\fR defaults to PRIMARY.
|
|
.RE
|
|
.SH EXAMPLES
|
|
.PP
|
|
On X11 platforms, one of the standard selections available is the
|
|
\fBSECONDARY\fR selection. Hardly anything uses it, but here is how to read
|
|
it using Tk:
|
|
.PP
|
|
.CS
|
|
set selContents [\fBselection get\fR \-selection SECONDARY]
|
|
.CE
|
|
.PP
|
|
Many different types of data may be available for a selection; the
|
|
special type \fBTARGETS\fR allows you to get a list of available types:
|
|
.PP
|
|
.CS
|
|
foreach type [\fBselection get\fR \-type TARGETS] {
|
|
puts "Selection PRIMARY supports type $type"
|
|
}
|
|
.CE
|
|
.PP
|
|
To claim the selection, you must first set up a handler to supply the
|
|
data for the selection. Then you have to claim the selection...
|
|
.CS
|
|
# Set up the data handler ready for incoming requests
|
|
set foo "This is a string with some data in it... blah blah"
|
|
\fBselection handle\fR \-selection SECONDARY . getData
|
|
proc getData {offset maxChars} {
|
|
puts "Retrieving selection starting at $offset"
|
|
return [string range $::foo $offset [expr {$offset+$maxChars-1}]]
|
|
}
|
|
|
|
# Now we grab the selection itself
|
|
puts "Claiming selection"
|
|
\fBselection own\fR \-command lost \-selection SECONDARY .
|
|
proc lost {} {
|
|
puts "Lost selection"
|
|
}
|
|
.CE
|
|
.SH "SEE ALSO"
|
|
clipboard(n)
|
|
.SH KEYWORDS
|
|
clear, format, handler, ICCCM, own, selection, target, type
|
|
'\" Local Variables:
|
|
'\" mode: nroff
|
|
'\" End:
|