headings and data of exports converted to event-driven

app/Events/Export/HeadingsPreparing.php

@@ -0,0 +1,20 @@
+<?php
+
+namespace App\Events\Export;
+
+use App\Abstracts\Event;
+
+class HeadingsPreparing extends Event
+{
+    public $class;
+
+    /**
+     * Create a new event instance.
+     *
+     * @param $class
+     */
+    public function __construct($class)
+    {
+        $this->class = $class;
+    }
+}

app/Events/Export/RowsPreparing.php

@@ -0,0 +1,24 @@
+<?php
+
+namespace App\Events\Export;
+
+use App\Abstracts\Event;
+
+class RowsPreparing extends Event
+{
+    public $class;
+
+    public $rows;
+
+    /**
+     * Create a new event instance.
+     *
+     * @param $class
+     * @param $rows
+     */
+    public function __construct($class, $rows)
+    {
+        $this->class = $class;
+        $this->rows = $rows;
+    }
+}