qds/app/Mail/InvoiceNotification.php

<?php

namespace App\Mail;

use Illuminate\Bus\Queueable;
use Illuminate\Contracts\Queue\ShouldQueue;
use Illuminate\Mail\Mailable;
use Illuminate\Mail\Mailables\Content;
use Illuminate\Mail\Mailables\Envelope;
use Illuminate\Queue\SerializesModels;

class InvoiceNotification extends Mailable
{
    use Queueable, SerializesModels;

    public $invoiceNumber;


    /**
     * Create a new message instance.
     */
    public function __construct($invoiceNumber)
    {
        $this->invoiceNumber = $invoiceNumber;
    }

    public function build()
    {
       return $this->subject("Invoice Notification")
                    ->view('mail.invoice_notification') // Make sure this Blade exists
                    ->with([
                        'invoiceNumber' => $this->invoiceNumber, // Pass data to the Blade
                    ]);
    }

    /**
     * Get the message envelope.
     */
    public function envelope(): Envelope
    {
        return new Envelope(
            subject: 'Invoice Notification',
        );
    }

    /**
     * Get the message content definition.
     */
    public function content(): Content
    {
        return new Content(
            view: 'view.name',
        );
    }

    /**
     * Get the attachments for the message.
     *
     * @return array<int, \Illuminate\Mail\Mailables\Attachment>
     */
    public function attachments(): array
    {
        return [];
    }
}