Widget Types

You are viewing documentation for an unreleased version of Craft CMS. Please be aware that some pages, screenshots, and technical reference may still reflect older versions.

Plugins can provide custom widget types for the control panel dashboard by creating a class that implements craft\base\WidgetInterface (opens new window) and craft\base\WidgetTrait (opens new window). The class will serve both as a way to communicate various things about your widget type (with static methods), and as a model that widgets of its type will be instantiated with.

Each user controls what widgets are on their dashboard, and may have multiple instances of a single widget type—meaning widget settings can give a single widget type a great deal of flexibility.

# Widget Class

Scaffold a widget type with the generator:

php craft make widget-type --plugin=my-plugin

If you would prefer to write a widget class from scratch, it should extend craft\base\Widget (opens new window). Refer to Craft’s own widget classes (located in vendor/craftcms/cms/src/widgets/, or the craft\widgets namespace) for examples.

# Registering Custom Widget Types

Once you have created your widget class, you will need to register it with the Dashboard service, so Craft will know about it when populating the list of available widget types. Generator will add this code, for you.

<?php
namespace mynamespace;

use craft\events\RegisterComponentTypesEvent;
use craft\services\Dashboard;
use yii\base\Event;

class Plugin extends \craft\base\Plugin
{
    public function init()
    {
        Event::on(
            Dashboard::class,
            Dashboard::EVENT_REGISTER_WIDGET_TYPES,
            function(RegisterComponentTypesEvent $event) {
                $event->types[] = MyWidget::class;
            }
        );

        // ...
    }

    // ...
}

# Content

A widget’s content is determined by its getBodyHtml() method. This example renders a Twig template, but you can generate the HTML however you like:

public function getBodyHtml(): ?string
{
    return Craft::$app->getView()->renderTemplate('my-plugin/_widgets/my-widget', [
        'local' => 'Variables!',
    ]);
}

# JavaScript + CSS

If the widget depends on JavaScript or CSS, you must register the appropriate asset bundles from this method, as well.

Each widget is rendered inside a HTML element with an id attribute like widget1, widget2, widget42, and so on, where the number is the widget’s id in the database. To tie JavaScript logic to each instance of your widget, consider separating its implementation from initialization:

(function() {
    Craft.MyWidget = Garnish.Base.extend({
        $widget: null,
        init: function(id) {
            this.$widget = document.getElementById('#widget' + id);

            // ...
        },
    });
})()

Here, we’ve parameterized the Craft.MyWidget JavaScript object so it can be instantiated multiple times, each with a unique id argument. The init() function takes care of building the complete HTML ID, looking it up in the DOM, and storing it on that instance.

# Settings

Your widget’s getSettingsHtml() method should return a snippet that includes input elements with name attributes matching its public properties. Whenever a user creates or updates a widget, Craft will assign those values, save the widget to the database, and re-render it.

If you elect to not implement getSettingsHtml(), your widget will display a photo of Brad Bell.

# Validation

As with other Model (opens new window)s, widgets can declare validation rules (opens new window) by implementing a defineRules() method. Validation rules ensure your widget is always configured in a useful way.