Paypal integration with Laravel 5.1

I try to integrate payment gateway (paypal) with laravel 5.1, I found some solutions of laravel 4 but not for laravel 5.0 and above.

I have been follow all steps mention in this link. xroot/laravel-paypalpayment

But I am getting FatalErrorException in PaypalPaymentController.php line 10:

I am attaching code of Paypal Integration which i did. and Screen shot of Eror

Router.php

resource('payment','PaymentController');

app.php

Anouar\Paypalpayment\PaypalpaymentServiceProvider::class,
'Paypalpayment'   => Anouar\Paypalpayment\Facades\PaypalPayment::class,

PaypalPaymentController.php

    <?php
namespace my_app\Http\Controllers;
use Illuminate\Support\Facades\Cache;
use Illuminate\Http\Request;
use my_app\Http\Requests;
use my_app\Http\Controllers\Controller;
use Paypalpayment;
    class PaypalPaymentController extends Facades {
    private $_apiContext;
    private $_ClientId='AZt_MjouRUFKuN9UGRTZfG2NnN6c5qeRDPk4XLvv2RpgTUXZZhWHYLPX6sEazQL-kbiRU5116czfZF72';
    private $_ClientSecret='ECzJoFchZijyj7V660ua99-GB9NshQJ1oJcMhlXHM7WDWibnjWK7S6c1ujAXYYmIW-F864goSFwffKjV';

    public function __construct(){
        // ### Api Context
        // Pass in a `ApiContext` object to authenticate 
        // the call. You can also send a unique request id 
        // (that ensures idempotency). The SDK generates
        // a request id if you do not pass one explicitly. 
        $this->_apiContext = Paypalpayment:: ApiContext(
                Paypalpayment::OAuthTokenCredential(
                    $this->_ClientId,
                    $this->_ClientSecret
                )
        );
        // dynamic configuration instead of using sdk_config.ini
        $this->_apiContext->setConfig(array(
            'mode' => 'sandbox',
            'http.ConnectionTimeOut' => 30,
            'log.LogEnabled' => true,
            'log.FileName' => __DIR__.'/../PayPal.log',
            'log.LogLevel' => 'FINE'
        ));
    }
    /*
     * Create payment using credit card
     * url:payment/create
    */
    public function create(){
        // ### Address
        // Base Address object used as shipping or billing
        // address in a payment. [Optional]
        $addr= Paypalpayment::Address();
        $addr->setLine1("3909 Witmer Road");
        $addr->setLine2("Niagara Falls");
        $addr->setCity("Niagara Falls");
        $addr->setState("NY");
        $addr->setPostal_code("14305");
        $addr->setCountry_code("US");
        $addr->setPhone("716-298-1822");
        // ### CreditCard
        // A resource representing a credit card that can be
        // used to fund a payment.
        $card = Paypalpayment::CreditCard();
        $card->setType("visa");
        $card->setNumber("4417119669820331");
        $card->setExpire_month("11");
        $card->setExpire_year("2019");
        $card->setCvv2("012");
        $card->setFirst_name("Anouar");
        $card->setLast_name("Abdessalam");
        $card->setBilling_address($addr);
        // ### FundingInstrument
        // A resource representing a Payer's funding instrument.
        // Use a Payer ID (A unique identifier of the payer generated
        // and provided by the facilitator. This is required when
        // creating or using a tokenized funding instrument)
        // and the `CreditCardDetails`
        $fi = Paypalpayment::FundingInstrument();
        $fi->setCredit_card($card);
        // ### Payer
        // A resource representing a Payer that funds a payment
        // Use the List of `FundingInstrument` and the Payment Method
        // as 'credit_card'
        $payer = Paypalpayment::Payer();
        $payer->setPayment_method("credit_card");
        $payer->setFunding_instruments(array($fi));
        // ### Amount
        // Let's you specify a payment amount.
        $amount = Paypalpayment:: Amount();
        $amount->setCurrency("USD");
        $amount->setTotal("1.00");
        // ### Transaction
        // A transaction defines the contract of a
        // payment - what is the payment for and who
        // is fulfilling it. Transaction is created with
        // a `Payee` and `Amount` types
        $transaction = Paypalpayment:: Transaction();
        $transaction->setAmount($amount);
        $transaction->setDescription("This is the payment description.");
        // ### Payment
        // A Payment Resource; create one using
        // the above types and intent as 'sale'
        $payment = Paypalpayment:: Payment();
        $payment->setIntent("sale");
        $payment->setPayer($payer);
        $payment->setTransactions(array($transaction));
        // ### Create Payment
        // Create a payment by posting to the APIService
        // using a valid ApiContext
        // The return object contains the status;
        try {
            $payment->create($this->_apiContext);
        } catch (\PPConnectionException $ex) {
            return "Exception: " . $ex->getMessage() . PHP_EOL;
            var_dump($ex->getData());
            exit(1);
        }
        $response=$payment->toArray();

        echo"<pre>";
        print_r($response);
        //var_dump($payment->getId());
        //print_r($payment->toArray());//$payment->toJson();
    }  
    /*
        Use this call to get a list of payments. 
        url:payment/
    */
    public function index(){
        echo "<pre>";
        $payments = Paypalpayment::all(array('count' => 1, 'start_index' => 0),$this->_apiContext);
         print_r($payments);
    }
}

Error which is i am getting

via Chebli Mohamed