Parent Filter

Note

This filter rule is no longer being developed — its successor is the filter rule Filter-by-related, which covers this functionality as well.

The “Parent Filter” filter rule (package filter_parent, from MM 2.3) allows filtering items based on a parent-child relationship to another MetaModel. An item of the target MetaModel is linked to an item of the “parent” MetaModel via an attribute. The filter rule then filters for items that are connected to a specific parent element.

Optionally, a frontend widget can be rendered that allows visitors to select the parent element themselves.

With the “Static parameter” option, a pre-selectable value can be set in the MetaModels list and filter CE/FE module as an overridable filter setting — see Restricting Items in CE/FE Module MM List and MM Filter.

Installation

The filter rule is installed via the Contao Manager or Composer:

composer require metamodels/filter_parent

Settings when Creating the Filter Rule

Setting	Description
Type	Selection of the filter rule type — here: “Parent Filter”.
Enabled	Enables or disables this filter rule.
Comment	Free text field for describing the purpose of this filter rule.
Parent MetaModel	The MetaModel that serves as the parent level (the “parent” MetaModel).
Parent attribute	The attribute in the current MetaModel that establishes the relation to the parent element (e.g. a single-select attribute pointing to the parent MetaModel).

Settings for the Frontend Widget

Setting	Description
URL parameter	The key of the URL parameter for passing the filter value. Without input, the column name of the attribute is used. With auto_item, only the value — without key — is embedded in the URL.
URL type for the parameter	Defines whether the parameter is passed as a slug (friendly URL) or as a GET parameter (from MM 2.4) — see SEO
Static parameter	If this option is active, the filter value can be pre-set with an overridable selection from a dropdown in the content element/module.
Provide frontend widget	Renders a filter widget in the frontend.
Widget type	Display type of the frontend widget: Select — Dropdown list (default) Text — Text input field Radio — Radio buttons Checkbox — Checkboxes
Allow empty value	If this option is active and the URL parameter is empty, no filter is applied.
Label	Label of the filter widget.
Template	Template for the widget output.
Default	Pre-selected parent record in the frontend widget.
Allow empty selection	Adds an empty option (“All”).
Only assigned values	Shows only parent elements in the widget that are actually linked to at least one item.
Only remaining values	Shows only parent elements for which results still exist after applying other filters.
Ignore this filter for remaining values	This filter does not return its own options as a restriction when calculating remaining values.

Matching Attributes

The “Parent Filter” filter rule works with an attribute of the current MetaModel that establishes the relation to the parent MetaModel:

• Single select [select]