关于laravel 得手动分页问题

#vendor/laravel/framework/src/Illuminate/Database/Eloquent/Builder.php:480

public function paginate($perPage = null, $columns = ['*'], $pageName = 'page', $page = null)
{
        $query = $this->toBase();

        $total = $query->getCountForPagination();

        $this->forPage(
            $page = $page ?: Paginator::resolveCurrentPage($pageName),
            $perPage = $perPage ?: $this->model->getPerPage()
        );

        return new LengthAwarePaginator($this->get($columns), $total, $perPage, $page, [
            'path' => Paginator::resolveCurrentPath(),
            'pageName' => $pageName,
        ]);
}

public function __construct($items, $total, $perPage, $currentPage = null, array $options = [])
{
       　foreach ($options as $key => $value) {
            $this->{$key} = $value;
        }

        $this->total = $total;
        $this->perPage = $perPage;
        $this->lastPage = (int) ceil($total / $perPage);
        $this->path = $this->path != '/' ? rtrim($this->path, '/') : $this->path;
        $this->currentPage = $this->setCurrentPage($currentPage, $this->lastPage);
        $this->items = $items instanceof Collection ? $items : Collection::make($items);
}

use Illuminate\Pagination\LengthAwarePaginator;
use Illuminate\Pagination\Paginator;

　　public function show(Request $request){
　　　　 $real =  DB::table('blog')->where('uid',$uid)->select();         // 假设查出的数据
　　　　  
        $perPage = 1;                                                    // 每页显示数量
        if ($request->has('page')) {                                     // 请求是第几页，如果没有传page数据，则默认为1
                $current_page = $request->input('page');
                $current_page = $current_page <= 0 ? 1 :$current_page;
        } else {
                $current_page = 1;
        }

        $item = array_slice($real, ($current_page-1)*$perPage, $perPage); // 注释1

        $total = count($real);                                            // 查询总数

        $paginator =new LengthAwarePaginator($item, $total, $perPage, $current_page, [
                'path' => Paginator::resolveCurrentPath(),                // 注释2
                'pageName' => 'page',
        ]);
        

　　　　return response()->json(['result'=>$paginator])
   }

"result": {
    "current_page": 3,
    "data": [
　　　　 { 
　　　　　　"id": 5, 
　　　　　　"sys_id": 1,
　　　　　　"org_id": 2,
　　　　　  "user_id": 8, 
          "papaer_id": 26
　　　　　}
    ],
    "from": null,
    "last_page": 2,
    "next_page_url": null,
    "path": "http://www.text.tld/examination/show",
    "per_page": 2,
    "prev_page_url": "http://www.text.tld/examination/show?page=2",
    "to": null,
    "total": 3
  }