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Curses::Widgets::ComboBox.3pm

NAME

Curses::Widgets::ComboBox - Combo-Box Widgets

MODULE VERSION

$Id: ComboBox.pm,v 1.103 2002/11/03 23:34:50 corliss Exp corliss $

SYNOPSIS

   use Curses::Widgets::ComboBox;
 
 

   $cb = Curses::Widgets::ComboBox->new({
     CAPTION     => 'Select',
     CAPTIONCOL  => 'yellow',
     COLUMNS     => 10,
     MAXLENGTH   => 255,
     MASK        => undef,
     VALUE       => '',
     INPUTFUNC   => \&scankey,
     FOREGROUND  => 'white',
     BACKGROUND  => 'black',
     BORDER      => 1,
     BORDERCOL   => 'red',
     FOCUSSWITCH => "\t\n",
     CURSORPOS   => 0,
     TEXTSTART   => 0,
     PASSWORD    => 0,
     X           => 1,
     Y           => 1,
     READONLY    => 0,
     LISTITEMS   => [qw(foo bar wop)],
     });
 
 

   $cb->draw($mwh, 1);
 
 

   See the Curses::Widgets pod for other methods.
 
 

REQUIREMENTS

Curses

Curses::Widgets

Curses::Widgets::TextField

Curses::Widgets::ListBox

DESCRIPTION

Curses::Widgets::ComboBox provides simplified OO access to Curses-based combo-boxes. This widget essentially acts as text field widget, but upon a KEY_DOWN or ``\n'', a drop-down list is displayed, and the item selected is put in the text field as the value.

METHODS

new (inherited from Curses::Widgets)

   $cb = Curses::Widgets::ComboBox->new({
     CAPTION     => 'Select',
     CAPTIONCOL  => 'yellow',
     COLUMNS     => 10,
     MAXLENGTH   => 255,
     MASK        => undef,
     VALUE       => '',
     INPUTFUNC   => \&scankey,
     FOREGROUND  => 'white',
     BACKGROUND  => 'black',
     BORDER      => 1,
     BORDERCOL   => 'red',
     FOCUSSWITCH => "\t\n",
     CURSORPOS   => 0,
     TEXTSTART   => 0,
     PASSWORD    => 0,
     X           => 1,
     Y           => 1,
     READONLY    => 0,
     LISTITEMS   => [qw(foo bar wop)],
     });
 
 

The new method instantiates a new ComboBox object. The only mandatory key/value pairs in the configuration hash are X and Y. All others have the following defaults:

   Key         Default   Description
   ============================================================
   CAPTION       undef   Caption superimposed on border
   CAPTIONCOL    undef   Foreground colour for caption text
   COLUMNS          10   Number of columns displayed
   MAXLENGTH       255   Maximum string length allowed
   MASK          undef   Not yet implemented
   VALUE            ''   Current field text
   INPUTFUNC \&scankey   Function to use to scan for keystrokes
   FOREGROUND    undef   Default foreground colour
   BACKGROUND    undef   Default background colour
   BORDER            1   Display a border around the field
   BORDERCOL     undef   Foreground colour for border
   FOCUSSWITCH  "\t\n"   Characters which signify end of input
   CURSORPOS         0   Starting position of the cursor
   TEXTSTART         0   Position in string to start displaying
   PASSWORD          0   Subsitutes '*' instead of characters
   READONLY          0   Prevents alteration to content
   LISTLINES         5   Number of lines to display at a time 
                         in the drop-down list
   LISTCOLUMNS[COLUMNS]  Width of the drop-down list.  Defaults 
                         to the same length specified for the 
                         CombBox widget
   LISTITEMS        []   Items listed in drop-down list
 
 

The CAPTION is only valid when the BORDER is enabled. If the border is disabled, the field will be underlined, provided the terminal supports it.

If MAXLENGTH is undefined, no limit will be placed on the string length.

draw (inherited from Curses::Widgets::TextField)

   $cb->draw($mwh, 1);
 
 

The draw method renders the text field in its current state. This requires a valid handle to a curses window in which it will render itself. The optional second argument, if true, will cause the field's text cursor to be rendered as well.

popup

   $combo->popup;
 
 

This method causes the drop down list to be displayed. Since, theoretically, this list should never be seen unless it's being actively used, we will always assume that we need to draw a cursor on the list as well.

HISTORY

2001/12/09 --- First version of the combo box

AUTHOR/COPYRIGHT

(c) 2001 Arthur Corliss (corliss@digitalmages.com)