更新 'server/app/Admin/Controllers/ProductController.php'

临时修复产品分类不存在的情况

server/app/Admin/Controllers/ProductController.php

@@ -30,7 +30,11 @@ class ProductController extends AdminController
             $grid->column('id')->sortable();
             $grid->column('name')->label('info');
             $grid->column('cate_id')->display(function (){
-                return $this->cate->name;
+                if($this->cate){
+                    return $this->cate->name;
+                }else{
+                    return '';
+                }
             })->label('success');
             $grid->column('cover_img')->image('',80);
             $grid->column('cases')->display(function (){