？创建修改模版 报错。

看看控制器对应方法返回页面的时候有没有绑定categories

  public function show(Topic $topic)
    {
      $categories = Category::all();
      return view('topics.create_and_edit', compact('topic', 'categories'));
    }

    public function create(Topic $topic)
    {
        return view('topics.create_and_edit', compact('topic','categories'));
    }

代码如上，是这里吗？求大神指点。

感谢指点，找到问题了。 忘记加
$categories = Category::all();

@Fykex 点击 话题后报错！求解。。

/home/vagrant/Code/larabbs/app/Http/Controllers/TopicsController.php

use App\Models\Topic;
use Illuminate\Http\Request;
use App\Http\Controllers\Controller;
use App\Http\Requests\UserRequest;
use App\Http\Requests\TopicRequest;
use App\Models\Category;
use Auth;

class TopicsController extends Controller
{
    public function __construct()
    {
        $this->middleware('auth', ['except' => ['index', 'show']]);
    }

    public function index(Topic $topic)
    {
   $categories = Category::all();
        $topics = $topic->withOrder($request->order)->paginate(20);
        return view('topics.index', compact('topics'));
    }

    public function show(Topic $topic)
    {
      $categories = Category::all();
      return view('topics.create_and_edit', compact('topic', 'categories'));
    }

    public function create(Topic $topic)
    {
    $categories = Category::all();
        return view('topics.create_and_edit', compact('topic','categories'));
    }

  public function store(TopicRequest $request, Topic $topic)
   {
       $topic->fill($request->all());
       $topic->user_id = Auth::id();
       $topic->save();
Arguments
"Undefined variable: request"

把没用的楼层删除掉吧，另外可以编辑已经发布的楼层，不用一直发新的
debug要贴出具体的报错代码，同时贴出相关的路由、控制器、模型等代码



控制器如下

<?php

namespace App\Http\Controllers;

use App\Models\Topic;
use Illuminate\Http\Request;
use App\Http\Controllers\Controller;
use App\Http\Requests\UserRequest;
use App\Http\Requests\TopicRequest;
use App\Models\Category;
use Auth;

class TopicsController extends Controller
{
    public function __construct()
    {
        $this->middleware('auth', ['except' => ['index', 'show']]);
    }

    public function index(Topic $topic)
    {
     $categories = Category::all();
        $topics = $topic->withOrder($request->order)->paginate(20);
        return view('topics.index', compact('topics'));
    }

    public function show(Topic $topic)
    {
      $categories = Category::all();
      return view('topics.create_and_edit', compact('topic', 'categories'));
    }

@ayauper 错误很明显了，高亮的23行，$request不存在
需要将$request依赖注入到控制器中

public function index(Topic $topic,Request $request)