************************
FilteringResourceWrapper
************************

``FilteringResourceWrapper`` is a `Sling ResourceWrapper <https://sling.apache.org/apidocs/sling8/org/apache/sling/api/resource/ResourceWrapper.html>`_ that filters its descendant resources based on ``granite:hide`` BooleanEL property.

This wrapper needs to be applied to the container resource, such as the page root resource, and the dialog root resource.

Naturally Granite UI page components support this mechanic OOTB, such as
:granite:servercomponent:`/libs/granite/ui/components/coral/foundation/page`,
:granite:servercomponent:`/libs/granite/ui/components/coral/foundation/page/fragment`,
:granite:servercomponent:`/libs/granite/ui/components/shell/page`,
:granite:servercomponent:`/libs/granite/ui/components/shell/collectionpage`,
:granite:servercomponent:`/libs/granite/ui/components/shell/propertiespage`.

It is also smart enough to handle include component.
In that case, if the resource type is :granite:servercomponent:`/libs/granite/ui/components/coral/foundation/include`,
the included resource will also be wrapped by the wrapper,
allowing the descendant resources of the included resource to use ``granite:hide`` property.


Content Structure
=================

.. gnd:gnd::

   [granite:hide]

   /**
    * ``true`` to hide the resource; ``false`` otherwise.
    */
   - granite:hide (BooleanEL)


Example
=======

Given the following content structure::

   + /mycontainer
     - sling:resourceType = "my/container"
     + item1
       - sling:resourceType = "my/item"
     + item2
       - sling:resourceType = "my/item"
       - granite:hide = true
     + item3
       - sling:resourceType = "my/item"
     + item4
       - sling:resourceType = "granite/ui/components/coral/foundation/include"
       - path = "/mycontainer2"
   + /mycontainer2
     - sling:resourceType = "my/container2"
     + item1
       - sling:resourceType = "my/item"
     + item2
       - sling:resourceType = "my/item"
       - granite:hide = true

Assuming that ``my/container`` resource type implementation uses ``FilteringResourceWrapper`` to wrap its resource (``/mycontainer`` resource),
``/mycontainer/item2`` and ``/mycontainer2/item2`` will be excluded during traversal transparently, as if they are not there in the first place.


Component Development
=====================

To enable this mechanic, you can simply wrap the resource with :javadoc:`FilteringResourceWrapper <com/adobe/granite/ui/components/FilteringResourceWrapper.html>`:

.. code-block:: java

   resource = new FilteringResourceWrapper(resource, sling.getService(ExpressionResolver.class), slingRequest);