[pmwiki-devel] Select & Option Dropdown-list Markup

[Hans]

I am seeking some advise how to optimise some markup, and choose
good markup names.

The following are three markup definitions to produce <select>
<option> ... </option> and </select> tags. This in turn will provide a
dropdown selection box, which could be used in input forms and other
places. The markup is pretty basic and perhaps too general.

/*  (:select name [jsgoto]:)
This will produce a name and id for the select HTML tag.
jsgoto is optional, and when present the function will return a select
tag with an added hard-coded onchange javascript bit. This is useful
when selecting page urls, as by selecting you immediately will be
directed to the page selected, without having to click a submit button.
In conjunction with pagelist you can very simply build a dropdow menu
of pages of the current group for instance (see code below), as a
instant jump-to box. */

Markup('select', 'directives', '/\\(:select\\s+(.*?)\\s*(jsgoto|):\\)/e',
       "Keep(SelectMarkup(\$pagename, '$1', '$2'))");

function SelectMarkup($pagename, $id, $arg2 ) {
   if($arg2=='jsgoto')
      return "<select name='$id' id='$id'
        onchange='window.location.href=this.options[this.selectedIndex].value' >";
   else return "<select name='$id' id='$id' >";
}          

/*  (:option value label:)
This will generate option tags with value and label provided. If no
label text is specified, value will be used instead.  */

Markup('option', 'inline', '/\\(:option\\s+(.*?)\\s+(.*?)\\s*:\\)/e',
       "Keep(OptionMarkup(\$pagename, '$1', '$2'))");
function OptionMarkup($pagename, $val, $label) {
    if($label=="") $label = $val;
    return "<option value='$val' />$label</option>";
}          

/*  (:selectend:)
This closes the option list.  */

Markup('selectend', 'inline', '/\(:selectend:\\)/e', 
       "Keep('</select>')");

       
I got a drop-down page selection menu using pagelist
by adding this to Site.LocalTemplates:

!!!fmt=#selectmenu
drop-down page selection box
[@
[[#selectmenu]]
(:option {$ScriptUrl}?n={=$FullName} {=$Title}:)
[[#selectmenuend]]
@]

and putting into Site.SideBar:

(:input form action={*$PageUrl}:)
(:select menupage jsgoto:)
(:pagelist group={*$Group} fmt=#selectmenu :)
(:selectend:)
(:input submit post "Go to Page":)
(:input end:)

The part from (:select menupage .. to (:selectend:) works on its own
with the javascript goto. To have it working with  a form submit button
it needs the (:input form .. surrounding it, and an additional php condition
to handle the redirection (added in config.php):

# pick up 'menupag' selection from (:select  :) on submit
if(isset($_POST['menupage'])) 
    Redirect ($_POST['menupage']);
  
This could become a recipe perhaps, but I like to optimise the code,
and check for pitfalls, overlaps, security bugs, with your help
please!

I am aware that we may get one day an (:input select... ) markup, and
I played with a version for that first, before going with the close to
HTML terminology, as it makes the markup-writing for authors a bit
shorter.
    
-- 
Best,
 Hans