After much poking around I discovered that the {{set-parameter}} includelet merely sets up parameters in the context of the local connection. For the special cases 'lang', 'description', 'keywords', and 'html_title', these parameters are made accessible as variables within the Page object, and code in the view method of the Page object sets them as meta tags explicitly in a loop using template::head::add_meta.
However, as a general rule, parameters set using the {{set-parameter}} includelet are not set up as local properties of the page, and are not explicity written to meta tags.
By following through the code I discovered that parameters set by the {{set-parameter}} includelet are accessible via the parameter handing machinery of the ::xo::cc helper object. So by adding the following line to the section of code in the Page::view method that handles the setting of the meta tags, I was able to solve my problem by hard-coding the additional meta name that I wanted to add:
set meta(viewport) [xo::cc set perconnectionparam(viewport)]
In context that is:
...
#
# initialize and set the template variables, to be used by
# a. adp_compile/ adp_eval
# b. return_page/ adp_include
#
set header_stuff [::xo::Page header_stuff]
if {[info command ::template::head::add_meta] ne ""} {
set meta(language) [my lang]
set meta(description) [my description]
set meta(keywords) ""
set meta(viewport) [xo::cc set perconnectionparam(viewport)]
if {[my istype ::xowiki::FormPage]} {
set meta(keywords) [string trim [my property keywords]]
if {[my property html_title] ne ""} {
::xo::Page set_property doc title [my property html_title]
}
}
if {$meta(keywords) eq ""} {
set meta(keywords) [$context_package_id get_parameter keywords ""]
}
foreach i [array names meta] {
# don't set empty meta tags
if {$meta($i) eq ""} continue
template::head::add_meta -name $i -content $meta($i)
}
}
...
The most important learning point for me is therefore that the {{set-parameter}} includelet is not a method for setting meta tags in the document header, but a means of setting parameters in the connection context.
My second conclusion is that I now have questions!
- Is this an appropriate way to do this?
- Would it be better to write a simple includelet specifically to add the appropriate includes and meta tags needed for JQuery Mobile, instead of serving them via [[js:includes]] and the above hack from xowiki?
