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Visual(3pm) User Contributed Perl Documentation Visual(3pm)

NAME

Term::Visual - split-terminal user interface

SYNOPSIS

  #!/usr/bin/perl -w
  use strict;
  use Term::Visual;
  my $vt = Term::Visual->new(    Alias => "interface",
                              Errlevel => 0 );
  $vt->set_palette( mycolor   => "magenta on black",
                    thiscolor => "green on black" );
  my $window_id = $vt->create_window(
        Window_Name  => "foo",
        Status       => { 0 =>
                           { format => "template for status line 1",
                             fields => [qw( foo bar )] },
                          1 =>
                           { format => "template for status line 2",
                             fields => [ qw( biz baz ) ] },
                        },
        Buffer_Size  => 1000,
        History_Size => 50,
        Input_Prompt => "[foo] ", # Set the input prompt for the input line.
 
        Use_Title    => 0, # Don't use a titlebar 
        Use_Status   => 0, # Don't use a statusbar
        Title        => "Title of foo"  );
  POE::Session->create
    (inline_states => {
       _start         => \&start_handler,
       got_term_input => \&term_input_handler,
     }
    );
  sub start_handler {
    my $kernel = $_[KERNEL];
    # Tell the terminal to send me input as "got_term_input".
    $kernel->post( interface => send_me_input => "got_term_input" );
                    
    $vt->set_status_field( $window_id, bar => $value );
    $vt->set_input_prompt($window_id, "\$");
    $vt->print( $window_id, "my Window ID is $window_id" );
  }
  sub term_input_handler {
      my ($kernel, $heap, $input, $exception) = @_[KERNEL, HEAP, ARG0, ARG1];
      # Got an exception.  These are interrupt (^C) or quit (^\).
      if (defined $exception) {
        warn "got exception: $exception";
        exit;
      }
      $vt->print($window_id, $input);
  }
  # Only use delete_window if using multiple windows.
  $vt->delete_window( $window_id ); 
  $vt->shutdown;

DESCRIPTION

Term::Visual is a "visual" terminal interface for curses applications. It provides the split-screen interface you may have seen in console based IRC and MUD clients.

Term::Visual uses the POE networking and multitasking framework to support concurrent input from network sockets and the console, multiple timers, and more.

PUBLIC METHODS

Term::Visual->method();

Create and initialize a new instance of Term::Visual.

  my $vt = Term::Visual->new( 
                     Alias => "interface",
              Common_Input => 1,
              Tab_Complete => sub { ... },                 
                  Errlevel => 0 );
    

Alias is a session alias for POE.

Common_Input is an optional flag used
to globalize History_Position,
History_Size,
Command_History,
Data,
Data_Save,
Cursor,
Cursor_Save,
Tab_Complete,
Insert,
Edit_Position
in create_window(); Thus all windows created will have common input.

Tab_Complete is a handler for tab completion.

  Tab_Complete => sub {
    my $left = shift;
    my @return;
    my %complete = (
        foo => "foobar ",
        biz => "bizbaz ",
       );
    return $complete{$left};
   }
    

Tab_Complete is covered more indepth in the examples directory.

Errlevel not implemented yet.

Errlevel sets Term::Visual's error level.

  my $window_id = $vt->create_window( ... );
    

Set the window's name

  Window_Name => "foo"
    

Set the Statusbar's format

  Status => { 0 => # first statusline
               { format => "\0(st_frames)" .
                           " [" .
                           "\0(st_values)" .
                           "%8.8s" .
                           "\0(st_frames)" .
                           "] " .
                           "\0(st_values)" .
                           "%s",
                 fields => [qw( time name )] },
              1 => # second statusline
               { format => "foo %s bar %s",
                 fields => [qw( foo bar )] },
            }
    

Set the size of the scrollback buffer

  Buffer_Size => 1000
    

Set the command history size

  History_Size => 50
    

Set the input prompt of the window

  Input_Prompt => "foo"
    

Set the title of the window

  Title => "This is the Titlebar"
    

Don't use Term::Visual's Titlebar.

  Use_Title => 0
    

Don't use Term::Visual's StatusBar.

  Use_Status => 0
    

No need to declare Use_Status or Use_Title if you want to use the Statusbar or Titlebar.

send_me_input is a handler Term::Visual uses to send the client input from a keyboard and mouse.

create a handler for parsing the input in your POE Session.

  POE::Session->create
    (inline_states => {
       _start         => \&start_handler,
       got_term_input => \&term_input_handler,
     }
    );
    

POE's _start handler is a good place to tell Term::Visual how to send you input.

  sub start_handler {
    my $kernel = $_[KERNEL];
 
    # Tell the terminal to send me input as "got_term_input".
    $kernel->post( interface => send_me_input => "got_term_input" );
    ...
  }
    

Now create your "term_input_handler" to parse input. In this case we simply check for exceptions and print the input to the screen.

  sub term_input_handler {
    my ($kernel, $heap, $input, $exception) = @_[KERNEL, HEAP, ARG0, ARG1];
    # Got an exception.  These are interrupt (^C) or quit (^\).
    if (defined $exception) {
      warn "got exception: $exception";
      exit;
    }
    $vt->print($window_id, $input);
  }
    
Prints lines of text to the main screen of a window

  $vt->print( $window_id, "this is a string" );
  my @array = qw(foo bar biz baz);
  $vt->print( $window_id, @array );
    
  my $current_window = $vt->current_window;
  $vt->print( $current_window, "current window is $current_window" );
    
  my $window_name = $vt->get_window_name( $window_id );
    
  my $window_id = $vt->get_window_id( $window_name );
    
  $vt->delete_window($window_id);
    

or

  $vt->delete_window(@window_ids);
    
  my $validity = $vt->validate_window( $window_id );
    

or

  my $validity = $vt->validate_window( $window_name );
  if ($validity) { do stuff };
    
Return color palette or a specific colorname's description.

  my %palette = $vt->get_palette();
  my $color_desc = $vt->get_palette($colorname);
  my ($foo, $bar) = $vt->get_palette($biz, $baz);
    
Set the color palette or specific colorname's value.

  $vt->set_palette( color_name => "color on color" );
  $vt->set_palette( color_name => "color on color",
                    another    => "color on color" );
  NOTE: (ncolor, st_values, st_frames, stderr_text, stderr_bullet, statcolor)
         are set and used by Term::Visual internally.
         It is safe to redifine there values.
    
Once your color definitions are set in the palette you must insert color codes to your output. These are formatted as follows: "\0(ncolor)"

So if you wanted to print something with a color you could simply use:

  $vt->print( $window_id, "\0(color_name)My this is a wonderful color." );
    
  $vt->set_title( $window_id, "This is the new Title" );
    
  my $title = $vt->get_title( $window_id );
    
Switch between windows

  $vt->change_window( $window_id );
  $vt->change_window( 0 );
  ...
  $vt->change_window( 1 );
    
  $vt->set_status_format( $window_id,
            0 => { format => "template for status line 1",
                   fields  => [ qw( foo bar ) ] },
            1 => { format => "template for status line 2",
                   fields  => [ qw( biz baz ) ] }, );
    
  $vt->set_status_field( $window_id, field => "value" );
  $vt->set_status_field( $window_id, foo => "bar", biz => "baz" );
    
  $vt->set_input_prompt($window_id, "\$");
  $vt->set_input_prompt($window_id, "[foo]");
    
  columnize is used internally, but might be of use 
  externally as well.
  Arguments given to columnize must be a hash.
  key 'Items' must be an array reference.
  The default value for Maxwidth may change to $COLS.
  my $table = $vt->columnize( 
     Items => \@list, 
     Padding => 2, # default value and optional
     MaxColumns => 10, # default value and optional
     MaxWidth => 80 # default value and optional
  );
    
  bind is used for key bindings.
  our %Bindings = (
      Up   => 'history',
      Down => 'history',
       ...
  );
  $vt->bind(%Bindings);
  sub handler_history {
    my ($kernel, $heap, $key, $win) = @_[KERNEL, HEAP, ARG0, ARG2];
    if ($key eq 'KEY_UP') {
      $vt->command_history($win, 1);
    }
    else {
      $vt->command_history($win, 2);
    }
  }
  POE::Session->create(
      inline_states => {
          _start => \&handler_start,
          _stop  => \&handler_stop,
          history => \&handler_history,
          ...
      }
  );
    
  $vt->unbind('Up', 'Down');
  $vt->unbind(keys %Bindings);
    
  $vt->debug("message");
  Debugging must be turned on before using this.
  change sub DEBUG () { 0 } to 1 or
  add this to your program: 
  sub Term::Visual::DEBUG () { 1 }
  use Term::Visual;
    
  $vt->shutdown();
    

Internal Keystrokes

Move to BOL.
Back one character.
Switch Windows decrementaly.
Switch Windows incrementaly.
Not implemented yet.

Kill a Window.

Kill Term::Visual.
Delete a character.
Move to EOL.
Forward a character.
Backward delete character.
Accept a line.
Kill to EOL.
Refresh screen.
Next in history.
Previous in history.
Display input status.
Transpose characters.
Discard line.
Word rubout.
Capitalize word to right of cursor.
Uppercase WORD.
Lowercase word.
Forward one word.
Backward one word.
Delete a word forward.
Transpose words.
Toggle Insert mode.
If window is scrolled up, page all the way down.
Scroll down a page.
Scroll up a page.
Scroll up a line.
Scroll down a line.

Author

Except where otherwise noted, Term::Visual is Copyright 2002-2007 Charles Ayres. All rights reserved. Term::Visual is free software; you may redistribute it and/or modify it under the same terms as Perl itself.

Questions and Comments can be sent to lunartear@cpan.org

Please send bug reports and wishlist items to:
http://rt.cpan.org/NoAuth/ReportBug.html?Queue=Term-Visual

Acknowledgments

A Big thanks to Rocco Caputo.

Rocco has contributed to the development of Term::Visual In many ways.

Rocco Caputo <troc+visterm@pobox.com>

Thank you!

2021-01-08 perl v5.32.0