NAME¶
Tk::Reindex - change the base index of Text-like widgets
SYNOPSIS¶
use Tk::ReindexedText;
$t1=$w->ReindexedText(-linestart => 2);
use Tk::ReindexedROText;
$t2=$w->ReindexedROText(-linestart => 0);
DESCRIPTION¶
Creates a new widget class based on
Text-like widgets that can redefine
the line number base (normally
Text widgets start line numbers at 1),
or possibly other manipulations on indexes.
STANDARD OPTIONS¶
The newly-defined widget takes all the same options as the base widget, which
defaults to
Text.
- Name: lineStart
- Class: LineStart
- Switch: -linestart
- Sets the line number of the first line in the Text widget. The
default -toindexcmd and -fromindexcmd use this configuration
option.
-item Name: toIndexCmd fromIndexCmd
-item Class: ToIndexCmd FromIndexCmd
-item Switch: -toindexcmd -fromindexcmd
These two options specify callbacks that are called with a list of indexes
and are responsible for translating them to/from indexes that the base
Text widget can understand. The callback is passed the widget
followed by a list of indexes, and should return a list of translated
indexes. -toindexcmd should translate from 'user' indexes to
'native' Text-compatible indexes, and -fromindexcmd should
translate from 'native' indexes to 'user' indexes.
The default callbacks simply add/subtract the offset given by the
-linestart option for all indexes in 'line.character' format.
It would probably be prudent to make these functions inverses of each
other.
CLASS METHODS¶
- import
- To make new Reindex widgets, this function should be called via use
with the name of the Text-like base class that you are extending with
"Reindex" capability. 'use base(Tk::Reindex
Tk::nameofbasewidget)' should also be specified for that widget.
BUGS¶
I've used the word "indexes" instead of "indices" throughout
the documentation.
All the built-in perl code for widget bindings & methods will use the new
'user' indexes. Which means all this index manipulation might might break code
that is trying to parse/manipulate indexes. Or even assume that '1.0' is the
beginning index.
Tk::Text::Contents comes to mind.
AUTHOR¶
Andrew Allen <ada@fc.hp.com>
This code may be distributed under the same conditions as Perl.