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Curses::UI::Searchable.3pm

NAME

Curses::UI::Searchable - Add 'less'-like search abilities to a widget

CLASS HIERARCHY

  Curses::UI::Searchable - base class
 
 

SYNOPSIS

     package MyWidget;
 
     use Curses::UI::Searchable;
     use vars qw(@ISA);
     @ISA = qw(Curses::UI::Searchable);
 
     ....
 
     sub new () {
         # Create class instance $this.
         ....
 
         $this->set_routine('search-forward', \&search_forward);
         $this->set_binding('search-forward', '/');
         $this->set_routine('search-backward', \&search_backward);
         $this->set_binding('search-backward', '?');
     }
 
     sub layout_content() {
         my $this = shift;
 
         # Layout your widget's content.
         ....
 
         return $this;
     }
 
     sub number_of_lines() {
         my $this = shift;
 
         # Return the number of lines in
         # the widget's content.
         return ....
     }
 
     sub getline_at_ypos($;) {
         my $this = shift;
         my $ypos = shift; 
 
         # Return the content on the line 
         # where ypos = $ypos
         return ....
     }
 
 

DESCRIPTION

Using Curses::UI::Searchable, you can add 'less'-like search capabilities to your widget.

To make your widget searchable using this class, your widget should meet the following requirements:

*

make it a descendant of Curses::UI::Searchable

All methods for searching are in Curses::UI::Searchable. By making your class a descendant of this class, these methods are automatically inherited.

*

-ypos data member

The current vertical position in the widget should be identified by $this->{-ypos}. This y-position is the index of the line of content. Here's an example for a Listbox widget.

  -ypos
    |
    v
        +------+
    0   |One   |
    1   |Two   |
    2   |Three |
        +------+
 
 

*

method: number_of_lines ( )

Your widget class should have a method number_of_lines, which returns the total number of lines in the widget's content. So in the example above, this method would return the value 3.

*

method: getline_at_ypos ( YPOS )

Your widget class should have a method getline_at_ypos, which returns the line of content at -ypos YPOS. So in the example above, this method would return the value ``Two'' for YPOS = 1.

*

method: layout_content ( )

The search routines will set the -ypos of your widget if a match is found for the given search string. Your layout_content routine should make sure that the line of content at -ypos will be made visible if the draw method is called.

*

method: draw ( )

If the search routines find a match, $this->{-search_highlight} will be set to the -ypos for the line on which the match was found. If no match was found $this->{-search_highlight} will be undefined. If you want a matching line to be highlighted, in your widget, you can use this data member to do so (an example of a widget that uses this option is the Curses::UI::TextViewer widget).

*

bindings for searchroutines

There are two search routines. These are search_forward and search_backward. These have to be called in order to display the search prompt. The best way to do this is by creating bindings for them. Here's an example which will make '/' a forward search and '?' a backward search:

     $this->set_routine('search-forward'  , \&search_forward);
     $this->set_binding('search-forward'  , '/');
     $this->set_routine('search-backward' , \&search_backward);
     $this->set_binding('search-backward' , '?');
 
 

SEE ALSO

Curses::UI,

AUTHOR

Copyright (c) 2001-2002 Maurice Makaay. All rights reserved.

Maintained by Marcus Thiesen (marcus@cpan.thiesenweb.de)

This package is free software and is provided ``as is'' without express or implied warranty. It may be used, redistributed and/or modified under the same terms as perl itself.