将新目录添加到控制器后,抛出致命错误

After adding a new directory into controllers, fatal error thrown

我是 Laravel 的新手,在我向控制器添加新目录后,即 Admin,我更新了命名空间也更新了路由,但不知何故,我收到了致命错误异常。请帮我解决问题

App->Http->Controllers->Admin

<?php

namespace App\Http\Controllers\Admin;

class AdminController extends Controller
{
    public function index()
    {
        echo "admin controller";
    }

}

routes.php

Route::get('/admin', 'Admin\AdminController@index');

snapshot of directory structure

尝试

<?php
namespace App\Http\Controllers\Admin;

use App\Http\Controllers\Controller;

class AdminController extends Controller
{
    public function index()
    {
        echo "admin controller";
    }

}

注意 "use" 语句。我怀疑 Laravel 正在寻找此控制器扩展的控制器 class,但由于缺少该语句而无法找到它。