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 $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' , '?');
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.