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Custom tree handler

What to do if a time comes, and you need some fancy stuff done to tree items that django-sitetree does not support?

It might be that you need some special tree items ordering in a menu, or you want to render a huge site tree with all articles titles that are described by one tree item in Django admin, or god knows what else.

django-sitetree can facilitate on that as it allows tree handler customization with the help of SITETREE_CLS setting.

  1. Subclass sitetreeapp.SiteTree and place that class into a separate module for convenience.
  2. You may now override .apply_hook() to manipulate tree items before render, or any other method to customize handler to your exact needs.
  3. Define SITETREE_CLS in settings.py of your project, showing it a dotted path to the subclass.

Example:

myapp/mysitetree.py
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from sitetree.sitetreeapp import SiteTree


class MySiteTree(SiteTree):
    """Custom tree handler to test deep customization abilities."""

    def apply_hook(self, tree_items, sender):
        # Suppose we want to process only menu child items.
        if sender == 'menu.children':
            # Let's add 'Hooked: ' to resolved titles of every item.
            for item in tree_items:
                item.title_resolved = 'Hooked: %s' % item.title_resolved
        # Return items list mutated or not.
        return tree_items
myproject/settings.py
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...
SITETREE_CLS = 'myapp.mysitetree.MySiteTree'
...

Note

You might also be interested in the notes on overriding admin representation.