diff options
Diffstat (limited to 'Master/tlpkg/tlperl/lib/Tk/after.pod')
-rw-r--r-- | Master/tlpkg/tlperl/lib/Tk/after.pod | 168 |
1 files changed, 0 insertions, 168 deletions
diff --git a/Master/tlpkg/tlperl/lib/Tk/after.pod b/Master/tlpkg/tlperl/lib/Tk/after.pod deleted file mode 100644 index 97c61ba380b..00000000000 --- a/Master/tlpkg/tlperl/lib/Tk/after.pod +++ /dev/null @@ -1,168 +0,0 @@ -# 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. -# -# - -=head1 NAME - -Tk::after - Execute a command after a time delay - -=for category Binding Events and Callbacks - -=head1 SYNOPSIS - -S< >I<$widget>-E<gt>B<after>(I<ms>) - -S< >I<$id> = I<$widget>-E<gt>B<after>(I<ms>?,I<callback>?) - -S< >I<$id> = I<$widget>-E<gt>B<repeat>(I<ms>?,I<callback>?) - -S< >I<$widget>-E<gt>B<afterCancel>(I<$id>) - -S< >I<$id> = I<$widget>-E<gt>B<afterIdle>(I<callback>) - -S< >I<$widget>-E<gt>B<afterInfo>?(I<$id>)? - -S< >I<$id>-E<gt>B<time>(?I<delay>?) - -=head1 DESCRIPTION - -This method is used to delay execution of the program or to execute -a callback in background sometime in the future. - -In perl/Tk I<$widget>-E<gt>B<after> is implemented via the class C<Tk::After>, -and callbacks are associated with I<$widget>, and are automatically cancelled -when the widget is destroyed. An almost identical interface, but without -automatic cancel, and without repeat is provided via Tk::after method. - -=head2 Internal Details - -The internal Tk::After class has the following synopsis: - - $id = Tk::After->new($widget, tid, $time, 'once', callback); - $id = Tk::After->new($widget, tid, $time, 'repeat', callback); - $id->cancel; - $id->time(?delay?); - -$id is a Tk::After object, an array of 5 elements: - -I<$widget> is the parent widget reference. - -I<tid> is the internal timer id, a unique string. - -I<$time> is the string 'idle', representing an idle queue timer, or a -integer millisecond value. - -I<once> or I<repeat> specifies whether the timer is a one-time B<after> -event, or a repeating B<repeat> event. - -I<callback> specifies a Perl/Tk Tk::Callback object. - -=head1 Changing a B<repeat> timer interval - -It's posible to change a B<repeat> timer's delay value, or even cancel -any timer, using the B<time> method. If I<delay> is specified and -non-zero, a new timer delay is established. If I<delay> is zero the -timer event is canceled just as if I<$id>-E<gt>B<cancel> were invoked. -In all cases the current millisecond timer delay is returned. - -Note: the new timer delay will take effect on the I<subsequent> timer -event - this command will not cancel the pending timer event and -re-issue it with the new delay time. - -=head1 The after() method has several forms as follows: - -=over 4 - -=item I<$widget>-E<gt>B<after>(I<ms>) - -The value I<ms> must be an integer giving a time in milliseconds. -The command sleeps for I<ms> milliseconds and then returns. -While the command is sleeping the application does not respond to -events. - -=item I<$widget>-E<gt>B<after>(I<ms>,I<callback>) - -In this form the command returns immediately, but it arranges -for I<callback> be executed I<ms> milliseconds later as an -event handler. -The callback will be executed exactly once, at the given time. -The command will be executed in context of I<$widget>. -If an error occurs while executing the delayed command then the -L<Tk::Error|Tk::Error> mechanism is used to report the error. -The B<after> command returns an identifier (an object in the perl/Tk -case) that can be used to cancel the delayed command using B<afterCancel>. - -=item I<$widget>-E<gt>B<repeat>(I<ms>,I<callback>) - -In this form the command returns immediately, but it arranges -for I<callback> be executed I<ms> milliseconds later as an -event handler. After I<callback> has executed it is re-scheduled, -to be executed in a futher I<ms>, and so on until it is cancelled. - -=item I<$widget>-E<gt>B<afterCancel>(I<$id>) - -=item I<$id>-E<gt>B<cancel> - -Cancels the execution of a delayed command that -was previously scheduled. -I<$id> indicates which command should be canceled; it must have -been the return value from a previous B<after> command. -If the command given by I<$id> has already been executed (and -is not scheduled to be executed again) then B<afterCancel> -has no effect. - -=item I<$widget>-E<gt>B<afterCancel>(I<callback>) - -I<This form is not robust in perl/Tk - its use is deprecated.> -This command should also cancel the execution of a delayed command. -The I<callback> argument is compared with pending callbacks, -if a match is found, that callback is -cancelled and will never be executed; if no such callback is -currently pending then the B<afterCancel> has no effect. - -=item I<$widget>-E<gt>B<afterIdle>(I<callback>) - -Arranges for I<callback> to be evaluated later as an idle callback. -The script will be run exactly once, the next time the event -loop is entered and there are no events to process. -The command returns an identifier that can be used -to cancel the delayed command using B<afterCancel>. -If an error occurs while executing the script then the -L<Tk::Error|Tk::Error> mechanism is used to report the error. - -=item I<$widget>-E<gt>B<afterInfo>?(I<$id>)? - -This command returns information about existing event handlers. If no -I<$id> argument is supplied, the command returns a list of the -identifiers for all existing event handlers created by the B<after> -and B<repeat> commands for I<$widget>. If I<$id> is supplied, it -specifies an existing handler; I<$id> must have been the return value -from some previous call to B<after> or B<repeat> and it must not have -triggered yet or been cancelled. In this case the command returns a -list with three elements. The first element of the list is the -callback associated with I<$id>, the second element is either B<idle> -or the I<integer> timer millisecond value to indicate what kind of -event handler it is, and the third is a string I<once> or I<repeat> to -differentiate an B<after> from a B<repeat> event. - -=back - -The B<after>(I<ms>) and B<afterIdle> forms of the command -assume that the application is event driven: the delayed commands -will not be executed unless the application enters the event loop. -In applications that are not normally event-driven, -the event loop can be entered with the B<vwait> and B<update> commands. - -=head1 SEE ALSO - -L<Tk::Error|Tk::Error> -L<Tk::callbacks|Tk::callbacks> - -=head1 KEYWORDS - -cancel, delay, idle callback, sleep, time - -=cut |