GridField Custom Action - How to modify Value?

Silverstripe Version: 4.3

Question: How can i modify a ModelAdmin GridField Value using a Custom Action?

Hello you guys!
My question might sound a little confusing but i’ll explain as good and understandable as possible.

So. I made a ModelAdmin Class that works just fine and displays all values as i want.
And i made 2 Custom Action Providers. So, there is a numeric value in the GridField which either should be 0 or 1. And what i wanna do: If you click the button, the Value of this SPECIFIC GridField Row gets modified. How can i do that? How can i select and miodify a value from the row the action runs in? I show you the code, but its basically just standard. Everything works fine. I just need those Buttons “verify” and “decline” to alter the rows specific value…

I could NOT find a way to do it in the SS documentation. Or did i just overread it? Then please let me know! I would be so glad if you could help me out!

<?php

use SilverStripe\View\Requirements;

use SilverStripe\Forms\GridField\GridField_ColumnProvider;

use SilverStripe\Forms\GridField\GridField_ActionProvider;

use SilverStripe\Forms\GridField\GridField_FormAction;

use SilverStripe\Forms\GridField\GridField;

use App\Web\Newsletter\CommentAdmin;

use SilverStripe\Control\Controller;

class CommentAdminButtons implements GridField_ColumnProvider, GridField_ActionProvider 

{

    public function augmentColumns($gridField, &$columns) 

    {

        if (!in_array('Actions', $columns)) {

            $columns[] = 'Actions';

        }

    }

    public function getColumnAttributes($gridField, $record, $columnName) 

    {

        return ['class' => 'grid-field__col-compact'];

    }

    public function getColumnMetadata($gridField, $columnName) 

    {

        if ($columnName === 'Actions') {

            return ['title' => ''];

        }

    }

    public function getColumnsHandled($gridField) 

    {

        return ['Actions'];

    }

    public function getColumnContent($gridField, $record, $columnName) 

    {

        Requirements::css('resources/themes/efficon/css/admin.css');

        if (!$record->canEdit()) {

            return;

        }

        $field = GridField_FormAction::create(

            $gridField,

            "verify-btn","",

            "verify",

            array('RecordID' => $record->ID)

        );

        $field->addExtraClass("verify-btn");

        $field->setDescription('Kommentar freigeben');

        $declineField = GridField_FormAction::create(

            $gridField,

            "decline-btn",

            "",

            "decline",

            array('RecordID' => $record->ID)

        );

        $declineField->addExtraClass("decline-btn");

        $declineField->setDescription('Kommentar nicht veröffentlichen');

        return $field->Field(). $declineField->Field();

    }

    public function getActions($gridField) 

    {

        return array('verify', 'decline');

    }

    public function handleAction(GridField $gridField, $actionName, $arguments, $data) 

    {

        if(strtolower($actionName) == "verify") {

           // WANT TO MODIFY GRIDFIELD VALUE 

            return $ruck;

        }

        if(strtolower($actionName) == "decline") {

           // WANT TO MODIFY GRIDFIELD VALUE 

            return;

        }

        // output a success message to the user

        Controller::curr()->getResponse()->setStatusCode(

            200,

            'Do Custom Action Done.'

        );

    }

}

?>