将导出按钮组添加到yajra datatable laravel包

I am using yajra laravel datatables package version 6.0 and I want to add export button group But I do not know how can I implement that.

Suppose I have a SubscriberController class like this :

public function newsletterDatatable (Request $request) {
    $subscribers =  Subscriber::select(['sub_id', 'email', 'confirmed', 'created_at']);

    $datatable = app('datatables')->of($subscribers)
        ->orderBy('created_at', 'desc')
        ->addColumn('checkbox', '<input type="checkbox" name="item_id[]" value="{{$sub_id}}">');

        return $datatable->make(true);
    }

And in JS codes I have :

$('#allSubscribersTable').DataTable({
    processing: true,
    serverSide: true,
    "bSort": false,
    "responsive": true,
    dom: 'Bfrtip',
    buttons: [
        'copy', 'csv', 'excel', 'pdf', 'print'
    ],
    ajax: {
        url: '{!! route('admin.newsletterDatatable') !!}'
    },
    columns: [
        {data: 'checkbox', "width": "20px"}
    ]
});

As you can see I used buttons option on DataTable initialization but when table is shown there are not any export buttons.

On the buttons-export page on Docs is said that I should add below Code But I do not know where and how to use in my controller :

namespace App\DataTables;

use App\User;
use Yajra\Datatables\Services\DataTable;

class UsersDataTable extends DataTable {
    //...some default stubs deleted for simplicity.

    public function html() {
        return $this->builder()
                    ->columns($this->getColumns())
                    ->parameters([
                        'buttons' => ['export'],
                    ]);
    }
...

If anyone know please help me.

Add DataTable class to handle query and view. Use

php artisan datatables:make OrdersDataTable

Utilize ajax(), query() and html() methods here. Then in your SubscriberController class use App\DataTables\OrdersDataTable and render view.

Sample code of OrdersDataTable class-

<?php

namespace App\DataTables;

use App\Models\Order;

class OrdersDataTable extends DataTable
{
    /**
     * Display ajax response.
 *
 * @return \Illuminate\Http\JsonResponse
 */
public function ajax()
{
    return $this->datatables
        ->eloquent($this->query())
        ->addColumn('action',  function ($row) {

            return '<a class="details-item" data-target="#modal-details-item" data-uri="'.url('admin/orders/'.$row->id).'" href=""><i class="fa fa-eye"></i> View Details</a> ';

        })
        ->make(true);
}

/**
 * Get the query object to be processed by dataTables.
 *
 * @return \Illuminate\Database\Eloquent\Builder|\Illuminate\Database\Query\Builder|\Illuminate\Support\Collection
 */
public function query()
{
    //$query = Order::query();
    $query = Order::select('orders.id', 'products.title', 'sites.name', 'orders.created_at')
        ->orderBy('orders.created_at', 'desc')
        ->leftJoin('products', 'products.id','=','orders.product_id')
        ->leftJoin('sites', 'sites.id','=','orders.site_id');

    return $this->applyScopes($query);
}

/**
 * Optional method if you want to use html builder.
 *
 * @return \Yajra\Datatables\Html\Builder
 */
public function html()
{
   return $this->builder()
    ->columns($this->getColumns())
    ->parameters([
        'dom' => 'Bfrtip',
        'buttons' => ['csv', 'excel', 'print'],
    ]);
}

/**
 * Get columns.
 *
 * @return array
 */
protected function getColumns()
{
    return [
        'id' => ['data' => 'id', 'name' => 'orders.id'],
        'title' =>[ 'data' => 'title', 'name' => 'products.title'],
        'name' => ['data' => 'name', 'name' => 'sites.name'],
        'created_at' => ['data' => 'created_at', 'name' => 'orders.created_at'],
        'action' => ['data' => 'action', 'name' => 'action', 'className' => "text-right", 'orderable'=> false, 'searchable' => false] 

    ];
}

/**
 * Get filename for export.
 *
 * @return string
 */
protected function filename()
{
    return 'order_export_' . time();
}
}

And in your controller just render view. For details check this- https://datatables.yajrabox.com/service