add key method to properly allow changing column key

Author: pxpm

src/app/Library/CrudPanel/CrudColumn.php

@@ -25,6 +25,7 @@
  * @method self visibleInExport(bool $value)
  * @method self visibleInShow(bool $value)
  * @method self priority(int $value)
+ * @method self key(string $value)
  */
 class CrudColumn
 {
@@ -66,6 +67,24 @@ public static function name($name)
         return new static($name);
     }
 
+    /**
+     * Change the CrudColumn key
+     *
+     * @param  string  $key  New key for the column
+     * @return CrudColumn
+     */
+    public function key(string $key)
+    {
+        if(!isset($this->attributes['name'])) {
+            abort(500, 'Column name must be defined before changing the key.');
+        }
+        if ($this->crud()->hasColumnWhere('key', $this->attributes['key'])) {
+            $this->crud()->setColumnDetails($this->attributes['key'], array_merge($this->attributes, ['key' => $key]));
+        }
+        $this->attributes['key'] = $key;
+        return $this;
+    }
+
     /**
      * Remove the current column from the current operation.
      *