How to extend all magento 2 widgets?

Question

I'm trying to add extra configuration options to all widget configuration/edit screens, not just cms_static_block for example, but all available widget types.

I've managed to add an additional tab (under 'widget options') by looking at how magento itself does it, but how the forms/fields themselves are added is beyond me at this point.

There is an _addField($parameter) function in the class that adds the extra tab(which extends \Magento\Widget\Block\Adminhtml\Widget\Options and implements \Magento\Backend\Block\Widget\Tab\TabInterface), and shorting it (return false;) gives me an empty form (instead of the form of the previous tab) but I'm pretty sure I shouldn't mess with that. Instead I'm pretty sure I should be creating templates and overriding classes somewhere else.

Maybe someone can point me in the right direction?

Thanks in advance.

Answer 1

Tuns out I had to override Magento\Widget\Block\Adminhtml\Widget\Instance\Edit\Tab\Properties.

Options.php:

<?php

namespace Vendor\Module\Block\Adminhtml\Widget;

use Magento\Framework\DataObject;
use Vendor\Module\Service\HTTPService;

class Options extends \Magento\Widget\Block\Adminhtml\Widget\Instance\Edit\Tab\Properties {


public function addFields(){
    parent::addFields();

    $fieldset = $this->getMainFieldset();

    $checked = $this->getChecked($this->getData());

    $fieldset->addField(
        $this->getMainFieldsetHtmlId() . '_' . 'ven_service',
        'checkboxes',
        [
            'name' => __('parameters[ven_service][]'),
            'label' => __('Service'),
            'title' => __('Service'),
            'values' => $this->populateValues(),
            'checked' => $checked
        ]
    );       

    return $this;
}

}

adminhtml/di.xml:

<?xml version="1.0"?>
<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:framework:ObjectManager/etc/config.xsd">
    <preference for="Magento\Widget\Block\Adminhtml\Widget\Instance\Edit\Tab\Properties" type="Vendor\Module\Block\Adminhtml\Widget\Options"/>
</config>