title: Argument 1 passed to App\Mail\OrderPlaced::__construct()
body: <p>I want to display the information of an order in a placed.plade.php balde but it gives me error: <code>Argument 1 passed to App\Mail\OrderPlaced::__construct() must be an instance of App\Mail\ App\Order, null given, called in D:\wamp\www\aswakt\routes\web.php</code> on line 77
  even I pass an argument in the model constructor OrderPlaced.php.</p>
  <p><strong>web.php</strong></p>
  <pre><code>Route::get('/mailable', function(){
      $order = App\Order::find(1);
      return new App\Mail\OrderPlaced($order);
  });
  </code></pre>
  <p><strong>OrderPlaced.php</strong></p>
  <pre><code>public $order;
  public function __construct(Order $order)
      {
          $this-&gt;order = $order;
      }
  
      /**
       * Build the message.
       *
       * @return $this
       */
      public function build()
      {
          return $this-&gt;to($this-&gt;order-&gt;billing_email,$this-&gt;order-&gt;billing_name)
                      -&gt;bcc('another@another.com')
                      -&gt;subject('Order for aswak tinghir ')  
                      -&gt;markdown('emails.orders.placed');
      }
  </code></pre>
  <p><strong>placed.blade.php</strong></p>
  <pre><code>**Order ID:** {{ $order-&gt;id }}
  
  **Order Email:** {{ $order-&gt;billing_email }}
  
  **Order Name:** {{ $order-&gt;billing_name }}
  
  **Order Total:** ${{ round($order-&gt;billing_total / 100, 2) }}
  </code></pre>