Hello,

Thanks a lot for this tutorial, it was enlightening for me. In your example the first filter is a static one, the second is a dynamic one but manual (the user has to make a choice). I'm wondering if it is possible to make a dynamic and automatic filter like you did the dynamic manual one.

More precisely I'm wondering if your approach would be the good way to create a dependency between two fields a & b with the content of field b dependent of the user choice of the field a. The two fields are entity references and the two entities A & B are referencing a same third entity on which I count to filter the result of field b.

Sincerely,
Guillaume

I am trying to create a custom views filter that will add a new filter to determine the day of the week. Any recommendations on what I am doing wrong will be greatly appreciated. Below is what I have so far.

class todays_date_handler_filter_numeric extends NumericFilter {
  function operators(){
    $operators = parent::operators();
    $operators += array(
      'todays date' => array(
        'title' => $this->t('Is this day of the week'),
        'short' => $this->t('todays date'),
        'method' => 'op_day_of_week',
        'values' => 0,
      )
    );
    return $operators;

    function op_day_of_week($field) {
      $this->query->addWhereExpression($this->options['group'], 'DATE_FORMAT(NOW(),"%w")');
    }
  }
}

I want to add new operator using NumericFilter But I cann't do Can you Provide me a simple example

I saw minor status error - "error missing group" status in the category when adding filter in Views UI. So i added a group property in field array in module_name.views.inc file.

$data['node__field_custom_date']['event_date'] = array(
    'title' => t('Custom Dates'),
    'group' => t('Content'),
    'filter' => array(
      'title' => t('Event Date - By Year'),
      'help' => t('Specify Event Dates By Year.'),
      'field' => 'field_event_date_value',
      'id' => 'custom_filter_event_year'
    ),
  );

This is a useful and great post; many thanks for it.
In your previous article (Creating a custom Views field in Drupal 8), you have created a field.
How can we adapt this tutorial to create a filter that will handle this field? (Just a simple "string" filter)
I have tried to do it myself, but I end up with an error when I am trying to use the filter:

Unknown column 'node.my_added_view_field' in 'where clause'

Thank you for the article.
How to implement a filter with a list of values? I found this class, but there are no examples of how to use it - https://api.drupal.org/api/drupal/core%21modules%21options%21src%21Plugin%21views%21filter%21ListField.php/class/ListField/8.2. x
Thank you.

Hi,
Thanks a lot for this great post. I just wonder how it will be if we want to create custom filter for date.. Year for example.

Print year select list for and filter the content based on created field.
2017
2016
2015

One thing that needs to be done in addition to the above is to add the schema to your module. I had this bite me, where phpunit tests were failing due to schema validation issues.

This can basically be done by copying and modifying the views.filter.in_operator definition in views.filter.schema.yml:

views.filter.d8views_node_titles:
  type: views_filter
  label: 'Allowed node titles'
  mapping:
    operator:
      type: string
      label: 'Operator'
    value:
      type: sequence
      label: 'Values'
      sequence:
        type: string
        label: 'Value'
    expose:
      type: mapping
      label: 'Expose'
      mapping:
        reduce:
          type: boolean
          label: 'Reduce'
    group_info:
      mapping:
        group_items:
          sequence:
            type: views.filter.group_item.in_operator
            label: 'Group item'

How can we add filter for Global : Custom Text field column in a view. Also how can we append our query to the existing query.

Hi,
I saw many here interested about Year filter, I made some changes and I got it working with me. I created field called Year and then I used it in 3 content types and used the same field for that filter and exposed it.
here the code:
https://github.com/malasaad82/views_year_filter_drupal_8

This is the second or third time I've come here for help writing a custom filter. Thank you so much for writing it!

Hi,

I have a view and in that I have a integer field(f1). I created one more field by views field plugin(f2). I want to show the result only which has f1 and f2 equal.
How I can achieve it?

Thanks for the tut, it has been a massive help!

It took me hours to solve the naming convention for custom view filters schema files.

So here's some info that I hope will help.

In the example below I refer to code in this tutorial.

If you are using: -

$data['node_field_data']['nodes_titles'] = array(
  'title' => t('Node titles'),
  'filter' => array(
    'title' => t('Node titles'),
    'help' => t('Specify a list of titles a node can have.'),
    'field' => 'title',
    'id' => 'd8views_node_titles'
  ),
);

Then you will have a view filter handler with an id of d8views_node_titles.

In the example NodeTitles.php class file the following is used: -

    /**
     * Filters by given list of node title options.
     *
     * @ingroup views_filter_handlers
     *
     * @ViewsFilter("d8views_node_titles")
     */
    class NodeTitles extends InOperator {

This is where the ID of the view filter handler is defined, in the annotations.

This is also where the base view filter handler is extended (InOperator). To define a view filter schema for this view filter plugin and handler, create the following:-

Filename: config/schema/[modulename].filter.schema.yml

views.filter.d8views_node_titles:
  type: views.filter.in_operator
  label: Node titles'

The main key in the yaml file (views.filter.d8views_node_titles:) references the ID of the view filter plugin name defined in the file class annotation.

To find the relating view filter handler that needs to be utilised in the yaml file, look in /core/modules/views/config/schema/views.filters.schema.yml and find the operator, in this example in_operator. Then just reference it, as per the example above.

This is a simple example, but I hope it helps.

thanks,
Christian

Hello. Thanks for your useful articles.
I'm trying to create my own views filter based on the FilterPluginBase class and using with my own field, created via Field API.
I'm working on my own project which uses geographic countries and regions. A geographical entity in my project must have a country and can have or not have a region. I created my own field containing two integer values - country id and region id. I managed to create a field widget and a field formatter for this field.
But I encountered some problems upon creating custom views expanded filter for this field.

1. I can't understand how to fill correctly the array in the hook_field_views_data?
   There isn't any information which data about filter can be stored in this array?
2. It's unclear, how to fill up correctly the my_module.schema.yml file for my own filter.
3. I managed an expanded filter with two select boxes, it works, but I want to customize the address line in the browser. For example, now it displays

myproject.com/cities/?country_id=5&region_id=10

I need to use instead them the following

myproject.com/cities/?geo_id=5_10 

Is it possible to modify the filter this way?

Has anyone ever created a custom view filter that filters on a custom view field?
I am finding examples of a custom view filter for content fields but none for custom view fields.
I am wondering if it is even possible because a custom view field does not seem to be associated with a physical table so it’s not included in the view SQL query, so I can’t determine what table to associate the custom views filter with.
Here is a snippet

   'field' => array(
     'title' => t('All QC Completed'),
     'help'  => t('Checks to see if all containers on a shipment passed QC checks'),
     'id'    => 'all_qc_completed',
   ),
   'filter' => array(
     'title' => t('All QC Completed'),
     'help' => t('Specify Yes and No options for All QC Completed field in container.'),
     'id' => 'd8views_yes_no',
   ),
 );```
It throws an error like this
```SQLSTATE[42S22]: Column not found: 1054 Unknown column 'node.all_qc_completed' in 'where clause': ... AND (node.all_qc_completed IN (:db_condition_placeholder_2, :db_condition_placeholder_3))) ...```
(edited for brevity)

First of all I want to thank you because you helped out on this task about filtering by month and year.
I didn't any idea on how to complete that task, thanks!!!

On the other hand I come here to share my contribution because I managed to create custom filters by month and year, and I'm sure this will help many devs like me, this is the repository:
https://github.com/DarkteK/d8-views-custom-filter/tree/master/d8_filters

If that helped you somehow please just give one star on that project, that will make me happy!
Cheers!

I was hoping to a add a checkbox filter to a view where I would be a able to apply a group by statement or field length check. Can anyone help?