Adding Mechanisms to Color Cells in TablePlugin.

Description

This is an extension to TablePlugin (see TablePluginDev) to allow users to to do more.

The initial motivation was the ability to color a row by the value of one of its columns (for example, bugs color-coded by owner, or priority, etc). That was a relatively simple change, so I thought of other coloring schemes. Implementing these made the code TablePlugin.pm quite ugly so I built an extension package which actually does the work of figuring out a cell's color and hands that value back to TablePlugin.pm.

The diff to TablePlugin is a dozen lines (everything else is in the extension package) - all of it to set-up the hook and process additional TABLE attributes and preferences.

Is this of interest to the general community/TablePlugin writer?

Examples

Here are some examples (direct form the output, table data is omitted from code but is just as in the | X | syntax):

(assembling)....

Rows colored by color set

Just like TablePlugin (default)...

%TABLE{tableborder="0" cellpadding="3" cellspacing="1" headerbg="#AACCCC" databg="#DFffA5,#ffeeee" cellcoloring="horizontal"}%

this	that	those	these
when	did	fireflies	become
enslaved	into	cellphone	buttons?
why	is	our	calendar
so	enmeshed	in	fragments?
have	you	ever	washed a
baby	in	a	watermelon?

Columns colored by color set

%TABLE{tableborder="0" cellpadding="3" cellspacing="1" headerbg="#AACCCC" databg="#DFffA5,#ffeeee" cellcoloring="vertical"}%

this	that	those	these
when	did	fireflies	become
enslaved	into	cellphone	buttons?
why	is	our	calendar
so	enmeshed	in	fragments?
have	you	ever	washed a
baby	in	a	watermelon?

Alternates on the diagonal - two colors becomes chessboard (useless?)

%TABLE{tableborder="0" cellpadding="3" cellspacing="1" headerbg="#AACCCC" databg="#DFffA5,#ffeeee" cellcoloring="diagonal"}%

this	that	those	these
when	did	fireflies	become
enslaved	into	cellphone	buttons?
why	is	our	calendar
so	enmeshed	in	fragments?
have	you	ever	washed a
baby	in	a	watermelon?

Color code cell by cell value

%TABLE{tableborder="0" cellpadding="3" cellspacing="1" headerbg="#AACCCC" databg="#DFffA5,#DFA5ff,#ffeeee" cellcoloring="filter" bgfilter="Yes,No"}%

Who	Dishes	Lawn	Laundry
Maggie	Yes	No	--
Cynthia	No	Yes	Yes
Mommy	No	No	Yes
Johnny	--	Yes	Yes
Papa	Yes	Yes	Yes

Color code rows by column value

%TABLE{tableborder="0" cellpadding="3" cellspacing="1" headerbg="#AACCCC" databg="#DFA5ff,#ffDFA5,#A5ffD5,#ffeeee" cellcoloring="filterbycol:2" bgfilter="Cynthia,Johnny,Maggie"}%

Chore	Owner	Priority	Comment
garbage	Mommy	---	DNA experiment!
lawn	Cynthia	medium	"English garden"!
bills	Mommy	---	Knock! Knock!
laundry	Maggie	medium	Not a nudist camp!
garage	Papa	---	Sale!
dishes	Johnny	high	No forks!
vacuum	Maggie	low	Asthmosis!

Highlight a row, a column or both

%TABLE{tableborder="0" cellpadding="3" cellspacing="1" headerbg="#AACCCC" databg="#DFA5ff,#ffDFA5,#ffeeee" cellcoloring="highlight:4:3"}%

Name	Gender	Disposition	Comment
Mommy	F	chummy	Don't use my real name!
Cynthia	F	naughty	GTK, Ru2?
Papa	M	fickle	too much time
Maggie	F	slinky	mumblemumble
Johnny	M	lazy	GameBoy? (tm)

Silly #1

%TABLE{tableborder="0" cellpadding="3" cellspacing="1" headerbg="#AACCCC" databg="#DFA5ff,#ffDFA5,#ffeeee" cellcoloring="gradientdia"}%

This example changes the color gradiently on the diagnal (not really useful, but easy to implement).

this	that	those	these
when	did	fireflies	become
enslaved	into	cellphone	buttons?
why	is	our	calendar
so	enmeshed	in	fragments?
have	you	ever	washed a
baby	in	a	watermelon?

Silly #2

%TABLE{tableborder="0" cellpadding="3" cellspacing="1" headerbg="#AACCCC" databg="#DFA5ff,#ffDFA5,#A5ffDF,#ffeeee" cellcoloring="filtermix" bgfilter="wa,en,me"}%

This example highlights cells depending on whether they have particular substrings (in this case wa, en, me; with the colors #ffDFA5,#A5ffDF,#ffeeee, mixing the colors where more than one substring occurs).

this	that	those	these
when	did	fireflies	become
enslaved	into	cellphone	buttons?
why	is	our	calendar
so	enmeshed	in	fragments?
have	you	ever	washed a
baby	in	a	watermelon?

Implementations

If this is useful to folks, I can document more, implement CGI parameterization and put it all neatly together....

-- SlavaKozlov - 12 Feb 2002

I added an alpha version below. the diff to the TablePlugin, the extension, and some usage sample files.

-- SlavaKozlov - 13 Feb 2002

Was there any work to officially integrate this into TablePlugin???

-- JohnCavanaugh - 14 Mar 2003

I don't believe there was any attempt to officially integrate it into thw TWiki. It should relatively easy as much of the work is done outside of the TablePlugin code itself.

-- SlavaKozlov - 21 Aug 2003

The coloring extensions look neat but are too esoteric for general use, there could also be a performance impact. For those who want these extensions: A possible solution is to add a hook into the TablePlugin, e.g. the coloring extensions would be an add-on to the TablePlugin.

-- PeterThoeny - 22 Aug 2003

I like the cell coloring by filter. It could be useful in some of our uses of tables. Like highlighting action items which are open, etc.

I really don't like having to patch either the core or other plugins to get a plugin to work. Either package all of this up into a new ColoringTablePlugin or follow Peter's suggestion of enhancing the TablePlugin to allow extensions to it. The later is more flexible, but the former is probably faster and easier to implement.

I do like some of these capabilities. Thanks!

-- MartyBacke - 22 Aug 2003

I was looking here because I need also some kind of user driven extension of coloring table cells. With 3 lines of code added to the TablePlugin I can define

%TABLE{ databg="none" tableborder="0" cellspacing="3" cellpadding="3" valign="top"}%
| %CLASS{onecolor}% Zeile 1 | weiterer Text%BR%zweite Zeile |
| %CLASS{anothercolor}% Zeile 2 | weiterer Text |
| %CLASS{onecolor}% Zeile 3 | asdfffff |

Zeile 1	weiterer Text zweite Zeile
Zeile 2	weiterer Text
Zeile 3	asdfffff

...
               $cell = "$color $cell ";
               $cell .= "" if( $color );
            }
# added code
            if ( $cell =~ s/(.*)%CLASS{(.*)}%// ) {
              $attr .= " class=\"$2\"";
            }
# end added code
            $text .= "<$type$attr>$cell";
            $text .= "";
            $colCount++;
        }

We need such more functional attributes defined better in style sheets than in hardcoded colors.
I'm not shure if tis is the right way %CLASS{...}% is not used as a real wiki macro. Is it possible to add such a feature to TablePlugin in this or another way. I hate it to patch own extensions after upgrades.

-- GuentherFischer - 13 Oct 2003

Is there a Plugin API for allowing one plugin to add handlers that other plugins could then use to carry out extension functions?

-- JadeCravy - 17 Jun 2006

There is no standard yet to extend Plugins by other Plugins. Please feel free to create a brainstorming topic in the Codev web.

-- PeterThoeny - 27 Jun 2006

Hm, couldn't this be done if the TablePlugin would be based on a kind of TableContrib that provides the basic features, thus making it possible to write an EnhancedTablePlugin without loosing backwards compatibility. Just a thought.

-- FranzJosefSilli - 28 Jun 2006

That is an option, yes. Another option is to enhance the TablePlugin with a callback feature where other Plugins can do additional manipulation. The other Plugin calls an install handler of the TablePlugin, the TablePlugin calls this handler when tables are rendered.

A clean solution is to enhance TWiki with an object oriented Plugins API where Plugins can override methods of other Plugins, and call the method of the super class if needed.

-- PeterThoeny - 28 Jun 2006