Magento 2 - It is posible to plug-in into a _construct method?

Question

It is possible?

di.xml

<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:framework:ObjectManager/etc/config.xsd">
    <type name="Magento\SalesRule\Block\Adminhtml\Promo\Quote">
        <plugin name="Vendor_Module::plugin_new" type="Vendor\Module\Plugin\New" sortOrder="1" disabled="true"/>
    </type>
</config>

New.php

namespace Vendor\Module\Plugin;
class New{
    public function before_construct(ChildBefore $subject, $interceptedInput)
    {
        echo '<pre>';
        var_dump($subject);
        var_dump($interceptedInput);
        echo '</pre>';
    return [&quot;(before) $interceptedInput (/before)&quot;];
}

}

score 3 · Accepted Answer · answered May 06 '16 at 12:08

3

No, unfortunately you can't. To overwrite _construct function, you have to use preference:

<preference for="Magento\SalesRule\Block\Adminhtml\Promo\Quote" type="Vendor\Module\Other\New" />

New.php

namespace Vendor\Module\Other;

class New extends Magento\SalesRule\Block\Adminhtml\Promo\Quote{
    protected function _construct()
    {
        echo '<pre>';
        [Your code here]
        echo '</pre>';

        return parent::_construct();
    }
}

answered May 06 '16 at 12:08

Bartłomiej Szubert

2,642
18
26

So, if a want to add a new button to that block-container Magento\SalesRule\Block\Adminhtml\Promo\Quote, how do i do it? Do i have to use preference by force? – Gianni Di Falco May 06 '16 at 12:12
Exactly, I don't think there is better option than preference. – Bartłomiej Szubert May 06 '16 at 12:14
3

No. For your particular problem, you can still use plugins. You just have to dig a little more: https://gist.github.com/adragus-inviqa/52faeb070b8f95f5f295820ddee2b406. Stop rewriting classes! There's TONS of ways to get your code in there. – nevvermind May 07 '16 at 11:06

score 2 · Answer 2 · edited Apr 13 '17 at 12:55

No, unfortunately plugins can only be used to to extend the behavior of any public method within a Magento class. Thus, they cannot be used to extend protected/private methods such as the _construct() method.

In order to modify those protected/private methods you will have to use preferences.

If you want to find out when and when not to use plugins I suggest you have a look at this great post: Rewriting Magento 2 classes vs Plugins

Magento 2 - It is posible to plug-in into a _construct method?

di.xml

New.php

2 Answers2