table of contents
Reindex(3) | perl/Tk Documentation | Reindex(3) |
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.
WIDGET-SPECIFIC OPTIONS¶
- 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.
2021-04-05 | Tk1.1 |