[development] breadcrumb override problem
drupal.beginner at wechange.org
Sun Jun 29 08:28:46 UTC 2008
I'm upgrading and cleaning directory.module for Drupal 6.
I am running on a breadcrumb problem.
I think the Drupal core implementation of breadcrumbs is broken.
First of all, there can only be one set of breadcrumbs.
Imagine a blog post outlined in some book, with a few taxonomy terms.
We potentially have three sets of breadcrumbs: the one set by each
module involved (blog, book, taxononomy, though core taxonomy.module
doesn't set the breadcrumbs on a node view.)
To decide which breadcrumb will prevail, timing is everything: it will
be the one set by the last call of drupal_set_breadcrumb() BEFORE the
first call of drupal_get_breadcrumb().
I was trying to override the taxonomy.module's breadcrumbs on a
taxonomy/term/nnn page, but:
- if I call drupal_set_breadcrumb() from hook_help(), it's too late:
the theming engine has already called drupal_get_breadcrumb() and my
breadcrumbs are ignored.
- if I call drupal_set_breadcrumb() from hook_init(), it's too early:
taxonomy.module will override mine just before drupal_get_breadcrumb()
So, now, I am a bit lost and don't know where I can best call
drupal_set_breadcrumb() so that it comes after taxonomy's call, and
before the first drupal_get_breadcrumb() call...
Searching d.o, I've found many other issues in other crontrib modules
which seem to deal with more or less the same problem, but I've not
found a solution yet.
1) how should I solve my particular problem (the timing of
drupal_set_breadcrumb() in my module to override/enhance taxonomy's
2) Do you agree that Drupal's core breadcrumbs handling could be
improved, to make it possible to have several sets of breadcrumbs
(why not? A good themer could accommodate them easily), or at least
to make it easier to override / complement each other's breadcrumbs.
If there's some kind of agreement on the second point, I'll open an
issue for D7 with a summary of the discussion here.
More information about the development