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

 Curses::UI::Searchable - base class

    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 ....
    }

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 CW$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, CW$this->{-search_highlight} will be set to the -ypos for the line on which the match was found. If no match was found CW$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' , '?');

Curses::UI,

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.