bind.n

linux系统下的音频通信

.IP \fB%c\fR 5
The \fIcount\fR field from the event.  Valid only for \fBExpose\fR events.
.IP \fB%d\fR 5
The \fIdetail\fR field from the event.  The \fB%d\fR is replaced by
a string identifying the detail.  For \fBEnter\fR,
\fBLeave\fR, \fBFocusIn\fR, and \fBFocusOut\fR events,
the string will be one of the following:
.RS
.DS
.ta 6c
\fBNotifyAncestor	NotifyNonlinearVirtual
NotifyDetailNone	NotifyPointer
NotifyInferior	NotifyPointerRoot
NotifyNonlinear	NotifyVirtual\fR
.DE
For events other than these, the substituted string is undefined.
.RE
.IP \fB%f\fR 5
The \fIfocus\fR field from the event (\fB0\fR or \fB1\fR).  Valid only
for \fBEnter\fR and \fBLeave\fR events.
.IP \fB%h\fR 5
.VS
The \fIheight\fR field from the event.  Valid only for \fBConfigure\fR and
\fBExpose\fR events.
.VE
.IP \fB%k\fR 5
The \fIkeycode\fR field from the event.  Valid only for \fBKeyPress\fR
and \fBKeyRelease\fR events.
.IP \fB%m\fR 5
The \fImode\fR field from the event.  The substituted string is one of
\fBNotifyNormal\fR, \fBNotifyGrab\fR, \fBNotifyUngrab\fR, or
.VS
\fBNotifyWhileGrabbed\fR.  Valid only for \fBEnter\fR,
\fBFocusIn\fR, \fBFocusOut\fR, and \fBLeave\fR events.
.VE
.IP \fB%o\fR 5
The \fIoverride_redirect\fR field from the event.  Valid only for
\fBMap\fR, \fBReparent\fR, and \fBConfigure\fR events.
.IP \fB%p\fR 5
The \fIplace\fR field from the event, substituted as one of the
strings \fBPlaceOnTop\fR or \fBPlaceOnBottom\fR.  Valid only
for \fBCirculate\fR events.
.IP \fB%s\fR 5
The \fIstate\fR field from the event.  For \fBButtonPress\fR,
\fBButtonRelease\fR, \fBEnter\fR, \fBKeyPress\fR, \fBKeyRelease\fR,
\fBLeave\fR, and \fBMotion\fR events, a decimal string
is substituted.  For \fBVisibility\fR, one of the strings
\fBVisibilityUnobscured\fR, \fBVisibilityPartiallyObscured\fR,
and \fBVisibilityFullyObscured\fR is substituted.
.IP \fB%t\fR 5
The \fItime\fR field from the event.  Valid only for events that
contain a \fItime\fR field.
.IP \fB%w\fR 5
The \fIwidth\fR field from the event.  Valid only for
.VS
\fBConfigure\fR and \fBExpose\fR events.
.VE
.IP \fB%x\fR 5
The \fIx\fR field from the event.  Valid only for events containing
an \fIx\fR field.
.IP \fB%y\fR 5
The \fIy\fR field from the event.  Valid only for events containing
a \fIy\fR field.
.IP \fB%A\fR 5
Substitutes the ASCII character corresponding to the event, or
the empty string if the event doesn't correspond to an ASCII character
(e.g. the shift key was pressed).  \fBXLookupString\fR does all the
work of translating from the event to an ASCII character.
Valid only for \fBKeyPress\fR and \fBKeyRelease\fR events.
.IP \fB%B\fR 5
The \fIborder_width\fR field from the event.  Valid only for
\fBConfigure\fR events.
.IP \fB%E\fR 5
The \fIsend_event\fR field from the event.  Valid for all event types.
.IP \fB%K\fR 5
The keysym corresponding to the event, substituted as a textual
string.  Valid only for \fBKeyPress\fR and \fBKeyRelease\fR events.
.IP \fB%N\fR 5
The keysym corresponding to the event, substituted as a decimal
number.  Valid only for \fBKeyPress\fR and \fBKeyRelease\fR events.
.IP \fB%R\fR 5
The \fIroot\fR window identifier from the event.  Valid only for
events containing a \fIroot\fR field.
.IP \fB%S\fR 5
The \fIsubwindow\fR window identifier from the event,
formatted as a hexadecimal number.
Valid only for events containing a \fIsubwindow\fR field.
.IP \fB%T\fR 5
The \fItype\fR field from the event.  Valid for all event types.
.IP \fB%W\fR 5
The path name of the window to which the event was reported (the
\fIwindow\fR field from the event).  Valid for all event types.
.IP \fB%X\fR 5
The \fIx_root\fR field from the event.
If a virtual-root window manager is being used then the substituted
value is the corresponding x-coordinate in the virtual root.
Valid only for
\fBButtonPress\fR, \fBButtonRelease\fR, \fBKeyPress\fR, \fBKeyRelease\fR,
and \fBMotion\fR events.
.IP \fB%Y\fR 5
The \fIy_root\fR field from the event.
If a virtual-root window manager is being used then the substituted
value is the corresponding y-coordinate in the virtual root.
Valid only for
\fBButtonPress\fR, \fBButtonRelease\fR, \fBKeyPress\fR, \fBKeyRelease\fR,
and \fBMotion\fR events.
.LP
The replacement string for a %-replacement is formatted as a proper
Tcl list element.
This means that it will be surrounded with braces
if it contains spaces, or special characters such as \fB$\fR and
\fB{\fR may be preceded by backslashes.
This guarantees that the string will be passed through the Tcl
parser when the binding script is evaluated.
Most replacements are numbers or well-defined strings such
as \fBAbove\fR;  for these replacements no special formatting
is ever necessary.
The most common case where reformatting occurs is for the \fB%A\fR
substitution.  For example, if \fIscript\fR is
.CS
\fBinsert\0%A\fR
.CE
and the character typed is an open square bracket, then the script
actually executed will be
.CS
\fBinsert\0\e[\fR
.CE
This will cause the \fBinsert\fR to receive the original replacement
string (open square bracket) as its first argument.
If the extra backslash hadn't been added, Tcl would not have been
able to parse the script correctly.

.SH MULTIPLE MATCHES
.PP
It is possible for several bindings to match a given X event.
If the bindings are associated with different \fItag\fR's,
then each of the bindings will be executed, in order.
By default, a binding for the widget will be executed first, followed
by a class binding, a binding for its toplevel, and
an \fBall\fR binding.
The \fBbindtags\fR command may be used to change this order for
a particular window or to associate additional binding tags with
the window.
.PP
The \fBcontinue\fR and \fBbreak\fR commands may be used inside a
binding script to control the processing of matching scripts.
If \fBcontinue\fR is invoked, then the current binding script
is terminated but Tk will continue processing binding scripts
associated with other \fItag\fR's.
If the \fBbreak\fR command is invoked within a binding script,
then that script terminates and no other scripts will be invoked
for the event.
.VS
.PP
If more than one binding matches a particular event and they
have the same \fItag\fR, then the most specific binding
is chosen and its script is evaluated.
The following tests are applied, in order, to determine which of
several matching sequences is more specific:
(a) an event pattern that specifies a specific button or key is more specific
than one that doesn't;
(b) a longer sequence (in terms of number
of events matched) is more specific than a shorter sequence;
(c) if the modifiers specified in one pattern are a subset of the
modifiers in another pattern, then the pattern with more modifiers
is more specific.
.VS
(d) a virtual event whose physical pattern matches the sequence is less
specific than the same physical pattern that is not associated with a 
virtual event.
(e) given a sequence that matches two or more virtual events, one 
of the virtual events will be chosen, but the order is undefined.
.PP
If the matching sequences contain more than one event, then tests
(c)-(e) are applied in order from the most recent event to the least recent
event in the sequences.  If these tests fail to determine a winner, then the
most recently registered sequence is the winner.
.PP
If there are two (or more) virtual events that are both triggered by the
same sequence, and both of those virtual events are bound to the same window
tag, then only one of the virtual events will be triggered, and it will
be picked at random:  
.CS
event add <<Paste>> <Control-y>
event add <<Paste>> <Button-2>
event add <<Scroll>> <Button-2>
bind Entry <<Paste>> {puts Paste}
bind Entry <<Scroll>> {puts Scroll}
.CE
If the user types Control-y, the \fB<<Paste>>\fR binding
will be invoked, but if the user presses button 2 then one of
either the \fB<<Paste>>\fR or the \fB<<Scroll>>\fR bindings will
be invoked, but exactly which one gets invoked is undefined.
.VE
.PP
If an X event does not match any of the existing bindings, then the
event is ignored.
An unbound event is not considered to be an error.

.SH "MULTI-EVENT SEQUENCES AND IGNORED EVENTS"
.PP
When a \fIsequence\fR specified in a \fBbind\fR command contains
more than one event pattern, then its script is executed whenever
the recent events (leading up to and including the current event)
match the given sequence.  This means, for example, that if button 1 is
clicked repeatedly the sequence \fB<Double-ButtonPress-1>\fR will match
each button press but the first.
If extraneous events that would prevent a match occur in the middle
of an event sequence then the extraneous events are
ignored unless they are \fBKeyPress\fR or \fBButtonPress\fR events.
For example, \fB<Double-ButtonPress-1>\fR will match a sequence of
presses of button 1, even though there will be \fBButtonRelease\fR
events (and possibly \fBMotion\fR events) between the
\fBButtonPress\fR events.
Furthermore, a \fBKeyPress\fR event may be preceded by any number
of other \fBKeyPress\fR events for modifier keys without the
modifier keys preventing a match.
For example, the event sequence \fBaB\fR will match a press of the
\fBa\fR key, a release of the \fBa\fR key, a press of the \fBShift\fR
key, and a press of the \fBb\fR key:  the press of \fBShift\fR is
ignored because it is a modifier key.
Finally, if several \fBMotion\fR events occur in a row, only
the last one is used for purposes of matching binding sequences.

.SH ERRORS
.PP
If an error occurs in executing the script for a binding then the
\fBbgerror\fR mechanism is used to report the error.
The \fBbgerror\fR command will be executed at global level
(outside the context of any Tcl procedure).

.SH "SEE ALSO"
bgerror

.SH KEYWORDS
form, manual