POE::Wheel::Curses(3) User Contributed Perl Documentation POE::Wheel::Curses(3)

POE::Wheel::Curses - non-blocking input for Curses

use Curses;
use POE qw(Wheel::Curses);
POE::Session->create(
  inline_states => {
    _start => sub {
      $_[HEAP]{console} = POE::Wheel::Curses->new(
        InputEvent => 'got_keystroke',
      );
    },
    got_keystroke => sub {
      my $keystroke = $_[ARG0];
      # Make control and extended keystrokes printable.
      if ($keystroke lt ' ') {
        $keystroke = '<' . uc(unctrl($keystroke)) . '>';
      }
      elsif ($keystroke =~ /^\d{2,}$/) {
        $keystroke = '<' . uc(keyname($keystroke)) . '>';
      }
      # Just display it.
      addstr($keystroke);
      noutrefresh();
      doupdate;
      # Gotta exit somehow.
      delete $_[HEAP]{console} if $keystroke eq "<^C>";
    },
  }
);
POE::Kernel->run();
exit;

POE::Wheel::Curses implements non-blocking input for Curses programs.

POE::Wheel::Curses will emit an "InputEvent" of your choosing whenever an input event is registered on a recognized input device (keyboard and sometimes mouse, depending on the curses library). Meanwhile, applications can be doing other things like monitoring network connections or child processes, or managing timers and stuff.

POE::Wheel::Curses is rather simple.

new() creates a new POE::Wheel::Curses object. During construction, the wheel registers an input watcher for STDIN (via select_read()) and registers an internal handler to preprocess keystrokes.

new() accepts only one parameter "InputEvent". "InputEvent" contains the name of the event that the wheel will emit whenever there is input on the console or terminal. As with all wheels, the event will be sent to the session that was active when the wheel was constructed.

It should be noted that an application may only have one active POE::Wheel::Curses object.

These are the events sent by POE::Wheel::Curses.

"InputEvent" defines the event that will be emitted when POE::Wheel::Curses detects and reads console input. This event includes two parameters:

$_[ARG0] contains the raw keystroke as received by Curses::getch(). An application may process the keystroke using Curses::unctrl() and Curses::keyname() on the keystroke.

$_[ARG1] contains the POE::Wheel::Curses object's ID.

Mouse events aren't portable. As of October 2009, it's up to the application to decide whether to call mousemask().

Curses documents what can be done with Curses. Also see the man page for whichever version of libcurses happens to be installed (curses, ncurses, etc.).

POE::Wheel describes wheels in general.

The SEE ALSO section in POE contains a table of contents covering the entire POE distribution.

None known, although curses implementations vary widely.

Please see POE for more information about authors and contributors.

2022-06-02 perl v5.36.0