Introduction

List Behavior is a controller modifier used for easily adding a record list to a page. The behavior provides the sortable and searchable list with optional links on its records. The behavior provides the controller action index however the list can be rendered anywhere and multiple list definitions can be used.

List behavior depends on list column definitions and a model class. In order to use the list behavior you should add it to the $implement property of the controller class. Also, the $listConfig class property should be defined and its value should refer to the YAML file used for configuring the behavior options.

namespace Acme\Blog\Controllers;

class Categories extends \Backend\Classes\Controller
{
    public $implement = [
        \Backend\Behaviors\ListController::class
    ];

    public $listConfig = 'list_config.yaml';
}

Note: Very often the list and form behavior are used together in a same controller.

Configuring the List Behavior

The configuration file referred in the $listConfig property is defined in YAML format. The file should be placed into the controller's views directory. Below is an example of a typical list behavior configuration file:

# ===================================
#  List Behavior Config
# ===================================

title: Blog Posts
list: ~/plugins/acme/blog/models/post/columns.yaml
modelClass: Acme\Blog\Models\Post
recordUrl: acme/blog/posts/update/:id

The following fields are required in the list configuration file:

Field Description
title a title for this list.
list a configuration array or reference to a list column definition file, see list columns.
modelClass a model class name, the list data is loaded from this model.

The configuration options listed below are optional.

Option Description
filter filter configuration, see filtering the list.
recordUrl link each list record to another page. Eg: users/update:id. The :id part is replaced with the record identifier. This allows you to link the list behavior and the form behavior.
recordOnClick custom JavaScript code to execute when clicking on a record.
noRecordsMessage a message to display when no records are found, can refer to a localization string.
deleteMessage a message to display when records are bulk deleted, can refer to a localization string.
noRecordsDeletedMessage a message to display when a bulk delete action is triggered, but no records were deleted, can refer to a localization string.
recordsPerPage records to display per page, use 0 for no pages. Default: 0
perPageOptions options for number of items per page. Default: [20, 40, 80, 100, 120]
showPageNumbers displays page numbers with pagination. Disable this to improve list performance when working with large tables. Default: true
toolbar reference to a Toolbar Widget configuration file, or an array with configuration (see below).
showSorting displays the sorting link on each column. Default: true
defaultSort sets a default sorting column and direction when user preference is not defined. Supports a string or an array with keys column and direction.
showCheckboxes displays checkboxes next to each record. Default: false.
showSetup displays the list column set up button. Default: false.
showTree displays a tree hierarchy for parent/child records. Default: false.
treeExpanded if tree nodes should be expanded by default. Default: false.
customViewPath specify a custom view path to override partials used by the list, optional.

Adding a Toolbar

To include a toolbar with the list, add the following configuration to the list configuration YAML file:

toolbar:
    buttons: list_toolbar
    search:
        prompt: Find records

The toolbar configuration allows:

Option Description
buttons a reference to a controller partial file with the toolbar buttons. Eg: _list_toolbar.htm
search reference to a Search Widget configuration file, or an array with configuration.

The search configuration supports the following options:

Option Description
prompt a placeholder to display when there is no active search, can refer to a localization string.
mode defines the search strategy to either contain all words, any word or exact phrase. Supported options: all, any, exact. Default: all.
scope specifies a query scope method defined in the list model to apply to the search query. The first argument will contain the query object (as per a regular scope method), the second will contain the search term, and the third will be an array of the columns to be searched.
searchOnEnter setting this to true will make the search widget wait for the Enter key to be pressed before it starts searching (the default behavior is that it starts searching automatically after someone enters something into the search field and then pauses for a short moment). Default: false.

The toolbar buttons partial referred above should contain the toolbar control definition with some buttons. The partial could also contain a scoreboard control with charts. Example of a toolbar partial with the New Post button referring to the create action provided by the form behavior:

<div data-control="toolbar">
    <a
        href="<?= Backend::url('acme/blog/posts/create') ?>"
        class="btn btn-primary oc-icon-plus">New Post</a>
</div>

Filtering the List

To filter a list by user defined input, add the following list configuration to the YAML file:

filter: config_filter.yaml

The filter option should make reference to a filter configuration file path or supply an array with the configuration.

Defining List Columns

List columns are defined with the YAML file. The column configuration is used by the list behavior for creating the record table and displaying model columns in the table cells. The file is placed to a subdirectory of the models directory of a plugin. The subdirectory name matches the model class name written in lowercase. The file name doesn't matter, but the columns.yaml and list_columns.yaml are common names. Example list columns file location:

plugins/
  acme/
    blog/
      models/                  <=== Plugin Models Directory
        post/                  <=== Model Configuration Directory
          list_columns.yaml    <=== Model List Columns Config File
        Post.php               <=== model Class

The next example shows the typical contents of a list column definitions file.

# ===================================
#  List Column Definitions
# ===================================

columns:
    name: Name
    email: Email

Column Options

For each column can specify these options (where applicable):

Option Description
label a name when displaying the list column to the user.
type defines how this column should be rendered (see Column types below).
default specifies the default value for the column if value is empty.
searchable include this column in the list search results. Default: false.
invisible specifies if this column is hidden by default. Default: false.
sortable specifies if this column can be sorted. Default: true.
clickable if set to false, disables the default click behavior when the column is clicked. Default: true.
select defines a custom SQL select statement to use for the value.
valueFrom defines a model attribute to use for the source value.
displayFrom defines a model attribute to use for the display value.
relation defines a model relationship column.
useRelationCount use the count of the defined relation as the value for this column. Default: false
cssClass assigns a CSS class to the column container.
headCssClass assigns a CSS class to the column header container.
width sets the column width, can be specified in percents (10%) or pixels (50px). There could be a single column without width specified, it will be stretched to take the available space.
align specifies the column alignment. Possible values are left, right and center.
permissions the permissions that the current backend user must have in order for the column to be used. Supports either a string for a single permission or an array of permissions of which only one is needed to grant access.

Custom Value Selection

It is possible to change the source and display values for each column. If you want to source the column value from another column, do so with the valueFrom option.

other_name:
    label: Something Great
    valueFrom: name

If you want to keep the source column value but display a different value from the model attribute, use the displayFrom option.

status_code:
    label: Status
    displayFrom: status_label

This is mostly applicable when a model accessor is used to modify the display value. This is useful where you want to display a certain value, but sort and search by a different value.

public function getStatusLabelAttribute()
{
    return title_case($this->status_code);
}

Nested Column Selection

In some cases it makes sense to retrieve a column value from a nested data structure, such as a model relationship column or a jsonable array. The only drawback of doing this is the column cannot use searchable or sortable options.

content[title]:
    name: Title
    sortable: false

The above example would look for the value in PHP equivalent of $record->content->title or $record->content['title'] respectively. To make the column searchable, and for performance reasons, we recommend duplicating its value on the local database table using model events.

Available Column Types

There are various column types that can be used for the type setting, these control how the list column is displayed. In addition to the native column types specified below, you may also define custom column types.

Text

text - displays a text column, aligned left

full_name:
    label: Full Name
    type: text

Image

image - displays an image column with the option to resize the output.

avatar:
    label: Avatar
    type: image
    sortable: false
    width: 150
    height: 150
    options:
        quality: 80

See the image resizing article for more information on what options are supported.

Number

number - displays a number column, aligned right

age:
    label: Age
    type: number

You may also specify a custom number format, for example currency $99.00.

price:
    label: Price
    type: number
    format: "$%.2f"

Note: Both text and number columns support the format property as a string value, this property follows the formatting rules of the PHP sprintf() function

Switch

switch - displays a on or off state for boolean columns.

enabled:
    label: Enabled
    type: switch

Date & Time

datetime - displays the column value as a formatted date and time. The next example displays dates as Thu, Dec 25, 1975 2:15 PM.

created_at:
    label: Date
    type: datetime

You may also specify a custom date format, for example Thursday 25th of December 1975 02:15:16 PM:

created_at:
    label: Date
    type: datetime
    format: l jS \of F Y h:i:s A

You may also wish to set ignoreTimezone: true to prevent a timezone conversion between the date that is displayed and the date stored in the database, since by default the backend timezone preference is applied to the display value.

created_at:
    label: Date
    type: datetime
    ignoreTimezone: true

Note: the ignoreTimezone option also applies to other date and time related field types, including date, time, timesince and timetense.

Date

date - displays the column value as date format M j, Y

created_at:
    label: Date
    type: date

Time

time - displays the column value as time format g:i A

created_at:
    label: Date
    type: time

Time Since

timesince - displays a human readable time difference from the value to the current time. Eg: 10 minutes ago

created_at:
    label: Date
    type: timesince

Time Tense

timetense - displays 24-hour time and the day using the grammatical tense of the current date. Eg: Today at 12:49, Yesterday at 4:00 or 18 Sep 2015 at 14:33.

created_at:
    label: Date
    type: timetense

Select

select - allows to create a column using a custom select statement. Any valid SQL SELECT statement works here.

full_name:
    label: Full Name
    select: concat(first_name, ' ', last_name)

Selectable

selectable - takes the column value and matches it to the value in the record's available options. Take the following array as an example, if the record value is set to open then the Open value is displayed in the column.

['open' => 'Open', 'closed' => 'Closed']

The available options are defined on the model as dropdown options.

status:
    label: Status
    type: selectable

They can also be specified explicitly in the options value.

status:
    label: Status
    type: selectable
    options:
        pending: Pending
        active: Active

Relation

relation - allows to display related columns, you can provide a relationship option. The value of this option has to be the name of the Active Record relationship on your model. In the next example the name value will be translated to the name attribute found in the related model (eg: $model->name).

group:
    label: Group
    relation: groups
    select: name

To display a column that shows the number of related records, use the useRelationCount option.

users_count:
    label: Users
    relation: users
    useRelationCount: true

Note: Using the relation option on a column will load the value from the selected column into the attribute specified by this column. It is recommended that you name the column displaying the relation data without conflicting with existing model attributes as demonstrated in the examples below:

Best Practice:

 group_name:
     label: Group
     relation: group
     select: name

Poor Practice:

# This will overwrite the value of $record->group_id which will break accessing relations from the list view
group_id:
    label: Group
    relation: group
    select: name

Partial

partial - renders a partial, the path value can refer to a partial view file otherwise the column name is used as the partial name.

content:
    label: Content
    type: partial
    path: ~/plugins/acme/blog/models/comment/_content_column.htm

Inside the partial these variables are available: $value is the default cell value, $record is the model used for the cell and $column is the configured class object Backend\Classes\ListColumn. Here is an some example contents of the _content_column.htm file.

<?php if ($record->is_active): ?>
    <?= e($value) ?>
<?php endif ?>

Color Picker

colorpicker - displays a color from colorpicker column

color:
    label: Background
    type: colorpicker

Displaying the List

Usually lists are displayed in the index view file. Since lists include the toolbar, the view file will consist solely of the single listRender method call.

<?= $this->listRender() ?>

Multiple List Definitions

The list behavior can support multiple lists in the same controller using named definitions. The $listConfig property can be defined as an array where the key is a definition name and the value is the configuration file.

public $listConfig = [
    'templates' => 'config_templates_list.yaml',
    'layouts' => 'config_layouts_list.yaml'
];

Each definition can then be displayed by passing the definition name as the first argument when calling the listRender method:

<?= $this->listRender('templates') ?>

Using List Filters

Lists can be filtered by adding a filter definition to the list configuration. Similarly filters are driven by their own configuration file that contain filter scopes, each scope is an aspect by which the list can be filtered. The next example shows a typical contents of the filter definition file.

# ===================================
# Filter Scope Definitions
# ===================================

scopes:

    category:
        label: Category
        modelClass: Acme\Blog\Models\Category
        conditions: category_id in (:filtered)
        nameFrom: name

    status:
        label: Status
        type: group
        conditions: status in (:filtered)
        options:
            pending: Pending
            active: Active
            closed: Closed

    published:
        label: Hide published
        type: checkbox
        default: 1
        conditions: is_published <> true

    approved:
        label: Approved
        type: switch
        default: 2
        conditions:
            - is_approved <> true
            - is_approved = true

    created_at:
        label: Date
        type: date
        conditions: created_at >= ':filtered'

    published_at:
        label: Date
        type: daterange
        conditions: created_at >= ':after' AND created_at <= ':before'

Scope Options

For each scope you can specify these options (where applicable):

Option Description
label a name when displaying the filter scope to the user.
type defines how this scope should be rendered (see Scope types below). Default: group.
conditions specifies a raw where query statement to apply to the list model query, the :filtered parameter represents the filtered value(s).
scope specifies a query scope method defined in the list model to apply to the list query. The first argument will contain the query object (as per a regular scope method) and the second argument will contain the filtered value(s)
options options to use if filtering by multiple items, this option can specify an array or a method name in the modelClass model.
emptyOption an optional label for an intentional empty selection.
nameFrom if filtering by multiple items, the attribute to display for the name, taken from all records of the modelClass model.
default can either be integer (switch, checkbox, number) or array (group, date range, number range) or string (date).
permissions the permissions that the current backend user must have in order for the filter scope to be used. Supports either a string for a single permission or an array of permissions of which only one is needed to grant access.
dependsOn a string or an array of other scope names that this scope depends on. When the other scopes are modified, this scope will update.

Filter Dependencies

Filter scopes can declare dependencies on other scopes by defining the dependsOn scope option, which provide a server-side solution for updating scopes when their dependencies are modified. When the scopes that are declared as dependencies change, the defining scope will update dynamically. This provides an opportunity to change the available options to be provided to the scope.

country:
    label: Country
    type: group
    conditions: country_id in (:filtered)
    modelClass: October\Test\Models\Location
    options: getCountryOptions

city:
    label: City
    type: group
    conditions: city_id in (:filtered)
    modelClass: October\Test\Models\Location
    options: getCityOptions
    dependsOn: country

In the above example, the city scope will refresh when the country scope has changed. Any scope that defines the dependsOn property will be passed all current scope objects for the Filter widget, including their current values, as an array that is keyed by the scope names.

public function getCountryOptions()
{
    return Country::lists('name', 'id');
}

public function getCityOptions($scopes = null)
{
    if (!empty($scopes['country']->value)) {
        return City::whereIn('country_id', array_keys($scopes['country']->value))
            ->lists('name', 'id')
        ;
    }
    else {
        return City::lists('name', 'id');
    }
}

Note: Scope dependencies with type: group are only supported at this stage.

Available Scope Types

These types can be used to determine how the filter scope should be displayed.

Group

group - filters the list by a group of items, usually by a related model and requires a nameFrom or options definition. Eg: Status name as open, closed, etc.

status:
    label: Status
    type: group
    conditions: status in (:filtered)
    default:
        pending: Pending
        active: Active
    options:
        pending: Pending
        active: Active
        closed: Closed

Checkbox

checkbox - used as a binary checkbox to apply a predefined condition or query to the list, either on or off. Use 0 for off and 1 for on for default value

published:
    label: Hide published
    type: checkbox
    default: 1
    conditions: is_published <> true

Switch

switch - used as a switch to toggle between two predefined conditions or queries to the list, either indeterminate, on or off. Use 0 for off, 1 for indeterminate and 2 for on for default value

approved:
    label: Approved
    type: switch
    default: 1
    conditions:
        - is_approved <> true
        - is_approved = true

Date

date - displays a date picker for a single date to be selected. The values available to be used in the conditions property are:

  • :filtered: The selected date formatted as Y-m-d
  • :before: The selected date formatted as Y-m-d 00:00:00, converted from the backend timezone to the app timezone
  • :after: The selected date formatted as Y-m-d 23:59:59, converted from the backend timezone to the app timezone

    created_at: label: Date type: date minDate: '2001-01-23' maxDate: '2030-10-13' yearRange: 10 conditions: created_at >= ':filtered'

Date Range

daterange - displays a date picker for two dates to be selected as a date range. The values available to be used in the conditions property are:

  • :before: The selected "before" date formatted as Y-m-d H:i:s
  • :beforeDate: The selected "before" date formatted as Y-m-d
  • :after: The selected "after" date formatted as Y-m-d H:i:s
  • :afterDate: The selected "after" date formatted as Y-m-d

    published_at: label: Date type: daterange minDate: '2001-01-23' maxDate: '2030-10-13' yearRange: 10 conditions: created_at >= ':after' AND created_at <= ':before'

To use default value for Date and Date Range

\MyController::extendListFilterScopes(function($filter) {
    $widget->addScopes([
        'Date Test' => [
            'label' => 'Date Test',
            'type' => 'daterange',
            'default' => $this->myDefaultTime(),
            'conditions' => "created_at >= ':after' AND created_at <= ':before'"
        ],
    ]);
});

// Return value must be instance of carbon
public function myDefaultTime()
{
    return [
        0 => Carbon::parse('2012-02-02'),
        1 => Carbon::parse('2012-04-02'),
    ];
}

You may also wish to set ignoreTimezone: true to prevent a timezone conversion between the date that is displayed and the date stored in the database, since by default the backend timezone preference is applied to the display value.

published_at:
    label: Date
    type: daterange
    minDate: '2001-01-23'
    maxDate: '2030-10-13'
    yearRange: 10
    conditions: created_at >= ':after' AND created_at <= ':before'
    ignoreTimezone: true

Note: the ignoreTimezone option also applies to the date filter type as well.

Number

number - displays input for a single number to be entered. The value is available to be used in the conditions property as :filtered.

age:
    label: Age
    type: number
    default: 14
    conditions: age >= ':filtered'

Number Range

numberrange - displays inputs for two numbers to be entered as a number range. The values available to be used in the conditions property are:

  • :min: The minimum value, defaults to -2147483647
  • :max: The maximum value, defaults to 2147483647

You may leave either the minimum value blank to search everything up to the maximum value, and vice versa, you may leave the maximum value blank to search everything at least the minimum value.

visitors:
    label: Visitor Count
    type: numberrange
    default:
        0: 10
        1: 20
    conditions: visitors >= ':min' and visitors <= ':max'

Text

text - display text input for a string to be entered. You may specify a size attribute that will be injected in the input size attribute (default: 10).

username:
    label: Username
    type: text
    conditions: username = :value
    size: 2

Extending List Behavior

Sometimes you may wish to modify the default list behavior and there are several ways you can do this.

Overriding Controller Action

You may use your own logic for the index action method in the controller, then optionally call the List behavior index parent method.

public function index()
{
    //
    // Do any custom code here
    //

    // Call the ListController behavior index() method
    $this->asExtension('ListController')->index();
}

Overriding Views

The ListController behavior has a main container view that you may override by creating a special file named _list_container.htm in your controller directory. The following example will add a sidebar to the list:

<?php if ($toolbar): ?>
    <?= $toolbar->render() ?>
<?php endif ?>

<?php if ($filter): ?>
    <?= $filter->render() ?>
<?php endif ?>

<div class="row row-flush">
    <div class="col-sm-3">
        [Insert sidebar here]
    </div>
    <div class="col-sm-9 list-with-sidebar">
        <?= $list->render() ?>
    </div>
</div>

The behavior will invoke a Lists widget that also contains numerous views that you may override. This is possible by specifying a customViewPath option as described in the list configuration options. The widget will look in this path for a view first, then fall back to the default location.

# Custom view path
customViewPath: $/acme/blog/controllers/reviews/list

Note: It is a good idea to use a sub-directory, for example list, to avoid conflicts.

For example, to modify the list body row markup, create a file called list/_list_body_row.htm in your controller directory.

<tr>
    <?php foreach ($columns as $key => $column): ?>
        <td><?= $this->getColumnValue($record, $column) ?></td>
    <?php endforeach ?>
</tr>

Extending Column Definitions

You may extend the columns of another controller from outside by calling the extendListColumns static method on the controller class. This method can take two arguments, $list will represent the Lists widget object and $model represents the model used by the list. Take this controller for example:

class Categories extends \Backend\Classes\Controller
{
    public $implement = ['Backend.Behaviors.ListController'];

    public $listConfig = 'list_config.yaml';
}

Using the extendListColumns method you can add extra columns to any list rendered by this controller. It is a good idea to check the $model is of the correct type. Here is an example:

    Categories::extendListColumns(function($list, $model)
    {
        if (!$model instanceof MyModel) {
            return;
        }

        $list->addColumns([
            'my_column' => [
                'label' => 'My Column'
            ]
        ]);

    });

You may also extend the list columns internally by overriding the listExtendColumns method inside the controller class.

class Categories extends \Backend\Classes\Controller
{
    [...]

    public function listExtendColumns($list)
    {
        $list->addColumns([...]);
    }
}

The following methods are available on the $list object.

Method Description
addColumns adds new columns to the list
removeColumn removes a column from the list

Each method takes an array of columns similar to the list column configuration.

Inject CSS Row Class

You may inject a custom css row class by adding a listInjectRowClass method on the controller class. This method can take two arguments, $record will represent a single model record and $definition contains the name of the List widget definition. You may return any string value containing your row classes. These classes will be added to the row's HTML markup.

class Lessons extends \Backend\Classes\Controller
{
    [...]

    public function listInjectRowClass($lesson, $definition = null)
    {
        // Strike through past lessons
        if ($lesson->lesson_date->lt(Carbon::today())) {
            return 'strike';
        }
    }
}

A special CSS class nolink is available to force a row to be unclickable, even if the recordUrl or recordOnClick options are defined for the List widget. Returning this class in an event will allow you to make records unclickable - for example, for soft-deleted rows or for informational rows:

public function listInjectRowClass($record, $value)
{
    if ($record->trashed()) {
        return 'nolink';
    }
}

Overriding Column URL

You may specify the click action for a column record by overriding the listOverrideRecordUrl method. This method can return a string for a new backend URL or an array with a complex definition.

public function listOverrideRecordUrl($record, $definition = null)
{
    if ($record->is_active) {
        return 'acme/test/services/preview/' . $record->id;
    }
}

To override the onclick behavior return an array with the onclick key and change the url to null.

public function listOverrideRecordUrl($record, $definition = null)
{
    if ($record->is_banned) {
        return ['onclick' => "alert('Unable to click')", 'url' => null];
    }
}

To make a column unclickable entirely return an array with the clickable key set to false.

public function listOverrideRecordUrl($record, $definition = null)
{
    if ($record->is_disabled) {
        return ['clickable' => false];
    }
}

Extending Filter Scopes

You may extend the filter scopes of another controller from outside by calling the extendListFilterScopes static method on the controller class. This method can take the argument $filter which will represent the Filter widget object. Take this controller for example:

    Categories::extendListFilterScopes(function($filter) {
        // Add custom CSS classes to the Filter widget itself
        $filter->cssClasses = array_merge($filter->cssClasses, ['my', 'array', 'of', 'classes']);

        $filter->addScopes([
            'my_scope' => [
                'label' => 'My Filter Scope'
            ]
        ]);
    });

The array of scopes provided is similar to the list filters configuration.

You may also extend the filter scopes internally to the controller class, simply override the listFilterExtendScopes method.

class Categories extends \Backend\Classes\Controller
{
    [...]

    public function listFilterExtendScopes($filter)
    {
        $filter->addScopes([...]);
    }
}

The following methods are available on the $filter object.

Method Description
addScopes adds new scopes to filter widget
removeScope remove scope from filter widget

Extending the Model Query

The lookup query for the list database model can be extended by overriding the listExtendQuery method inside the controller class. This example will ensure that soft deleted records are included in the list data, by applying the withTrashed scope to the query:

public function listExtendQuery($query)
{
    $query->withTrashed();
}

When dealing with multiple lists definitions in a same controller, you can use the second parameter of listExtendQuery which contains the name of the definition :

public $listConfig = [
    'inbox' => 'config_inbox_list.yaml',
    'trashed' => 'config_trashed_list.yaml'
];

public function listExtendQuery($query, $definition)
{
    if ($definition === 'trashed') {
        $query->onlyTrashed();
    }
}

You may also join other tables to aid with searching and sorting. The following will join the post_statuses table and introduce the status_sort_order and status_name columns to the query.

public function listExtendQuery($query, $definition = null)
{
    $query->leftJoin('post_statuses', 'posts.status_id', 'post_statuses.id');

    $query->select(
        'posts.*',
        'post_statuses.sort_order as status_sort_order',
        'post_statuses.name as status_name'
    );
}

The list filter model query can also be extended by overriding the listFilterExtendQuery method:

public function listFilterExtendQuery($query, $scope)
{
    if ($scope->scopeName == 'status') {
        $query->where('status', '<>', 'all');
    }
}

Extending the Records Collection

The collection of records used by the list can be extended by overriding the listExtendRecords method inside the controller class. This example uses the sort method on the record collection to change the sort order of the records.

public function listExtendRecords($records)
{
    return $records->sort(function ($a, $b) {
        return $a->computedVal() > $b->computedVal();
    });
}

Custom Column Types

Custom list column types can be registered in the back-end with the registerListColumnTypes method of the Plugin registration class. The method should return an array where the key is the type name and the value is a callable function. The callable function receives three arguments, the native $value, the $column definition object and the model $record object.

public function registerListColumnTypes()
{
    return [
        // A local method, i.e $this->evalUppercaseListColumn()
        'uppercase' => [$this, 'evalUppercaseListColumn'],

        // Using an inline closure
        'loveit' => function($value) { return 'I love '. $value; }
    ];
}

public function evalUppercaseListColumn($value, $column, $record)
{
    return strtoupper($value);
}

Using the custom list column type is as simple as calling it by name using the type option.

# ===================================
#  List Column Definitions
# ===================================

columns:
    secret_code:
        label: Secret code
        type: uppercase

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