Difference between revisions of "Help:Collapsing"

Latest revision as of 09:13, 26 April 2014

Collapsible tables provide a way to collapse and uncollapse a table when a show/hide button is clicked. The code for this feature is found in the MediaWiki:Common.js.

The initial state of any collapsible content can be controlled using a "collapsible table", because it also allows a table with only one element with content, and a header.

Simple example

Tables are simpler to work with, as you merely need to add the collapsible class to the table itself. For the [hide]/[show] link to appear, the table's first row must be a header row, that is, one of the cells in the first row must be declared with an exclamation mark (in wikisyntax). The use of the class wikitable in the example below is merely for appearance; it is not needed for collapsible to function.

Code entered

Output produced

{| class="wikitable collapsible"
! Simple collapsible table
|-
| Lorem ipsum dolor sit amet
|}

Simple collapsible table
Lorem ipsum dolor sit amet

Using the syntax above, collapsible tables are often used to always display an introduction to, or summary of, a lengthy discussion or section of content, while hiding the majority of that content from immediate view. The summary message is put in the header cell, and the content is placed into the body cell. The content is then easily accessible by clicking the 'show' button. The collapsible functionality is also available in larger and more complicated tables, as long as there is a header cell in the first row of the table.

Code entered

Output produced

{| class="wikitable collapsible"
|A normal cell in the header row
! colspan="2"| Header cell spans two cols
|-
| colspan="2" | Lorem ipsum dolor sit amet
| Separate body cell
|}

A normal cell in the header row	Header cell spans two cols
Lorem ipsum dolor sit amet		Separate body cell

Collapsing tables by default

Just using the collapsible class produces a table which is expanded by default, but can be collapsed by the reader. It is also possible to create tables which are collapsed by default, and can be optionally expanded. There are several methods for doing this, depending on the situations in which you want the table to collapse.

"collapsed"

Adding the collapsed class will cause the table to always be initially collapsed, no matter what happens around it. It is the simplest method for doing so. Using the examples above:

Code entered

Output produced

{| class="wikitable collapsible collapsed"
! Simple collapsible table
|-
| Lorem ipsum dolor sit amet
|}

Simple collapsible table
Lorem ipsum dolor sit amet

{| class="wikitable collapsible collapsed"
|A normal cell in the header row
! colspan="2"| Header cell spans two cols
|-
| colspan="2" | Lorem ipsum dolor sit amet
| Separate body cell
|}

A normal cell in the header row	Header cell spans two cols
Lorem ipsum dolor sit amet		Separate body cell

"autocollapse"

Adding the autocollapse class causes the table to collapse when there are 2 or more collapsible tables on the page (this threshold might be different on other projects). The example below, therefore, collapses because there are numerous collapsible tables on the page.

Code entered

Output produced

{| class="wikitable collapsible autocollapse"
! Simple collapsible table
|-
| Lorem ipsum dolor sit amet
|}

Simple collapsible table
Lorem ipsum dolor sit amet

"innercollapse" and "outercollapse"

Using this pair of classes, it is possible to make a table collapsed by default only when it is contained within a particular object, such as another table. This is mainly useful for tables inside templates, which are often nested.

Code entered

Output produced

{| class="wikitable outercollapse"
! This table does not collapse
|-
| But the table inside this cell

{| class="wikitable collapsible innercollapse"
! Does collapse
|-
| Hiding this part
|}

|}

This table does not collapse

But the table inside this cell

Does collapse
Hiding this part

Other notes

Sortable tables

Collapsible tables can be combined with the sortable tables functionality without difficulty. However, because the hide/show button is placed in the first header cell located, its positioning can look a bit peculiar if the cell is not wide enough:

Code entered

Output produced

{|class="wikitable collapsible sortable" style="width:5em"
<!--table width too narrow, on purpose here-->
|-
!scope="col"|Name!!scope="col"|Score
|-
|John||59
|-
|Jane||100
|-
|Bob||72
|}

Name	Score
John	59
Jane	100
Bob	72

Possible alternative (that appears quite horrible from utility point of view, though) is sortable table inside one-cell collapsible table whose header will be as large as the full table embedded below. See the following example.

Code entered

Output produced

{|class="wikitable collapsible collapsed" style="border:none"
|-
!scope="col"|header
|-
|style="padding:0;border:none"|
{|class="wikitable sortable" style="margin:0;width:100%"
|-
!scope="col"|a!!scope="col"|b
|-
|3||4
|-
|5||6
|}
|}

header

a	b
3	4
5	6

Customization

Registered users can edit their personal js file file to change some of the variables used.

autoCollapse = 4 //how many collapsible tables on the page before autocollapse works (default=2)
var collapseCaption = 'collapse' //text of the [hide] link (default='hide')
var expandCaption = 'uncollapse' //text of the [show] link (default='show')

Other HTML elements

The code that performs the manipulation only checks for table elements, so these classes will not work for other elements, such as <div> or <span>. There is a similar feature for use with <div> elements, called "NavFrame".

Limitations

This functionality requires the end-user's browser to have JavaScript enabled. If Javascript is disabled, the default behaviour is to show the content.