只有当产品带有Laravel时，才能在菜单上显示子类别

Question

我有一个简单的查询，它用主类别和子类别填充菜单。这项工作非常

// in controller 
$cat=Categories::all(); 
View::share('categories_menu',$cat); 

// in view 
@foreach($categories_menu as $category_menu) 
    @if($category_menu->has('subcategories')) 
     <ul class="nav nav-stacked cat-nav"> 
       <li> 
        <a href="#">{{ $category_menu['category_name'] }} </a> 
         @if($category_menu->subcategories->count()) 
          <ul> 
          @foreach($category_menu->subcategories as $subcategory) 
           <li class=""><a href="#">{{$subcategory->sub_cat_name}}</a></li> 
          @endforeach 
          </ul> 
         @endif 
       </li> 
      @else 
       <li><a href="#"><i class="fa fa-link"></i> <span>{{ $category_menu->category_name }}</span></a></li> 
      @endif 
     </ul> 
@endforeach 

本作输出像

Main Category 
    -Sub Cat 
    -Sub Cat 
Second main category 
    -Sub in second main category 
    ... 

的问题是，它是装也分类别，其是空的。我不想告诉他们，我试图与加入所有三个表更改查询 - category，sub_categories，products

这是查询到目前为止

$cat = Categories::select('*', DB::raw('category.category_id AS category_id')) 
    ->leftJoin('products', function($join) { 
      $join->on('products.category_id', '=', 'category.category_id'); 
      }) 
    ->leftJoin('sub_category', function($secondjoin){ 
      $secondjoin->on('sub_category.category_id', '=', 'category.category_id'); 
      }) 
    ->whereNotNull('products.sub_cat_id') 
    ->get(); 

结果是怪（图）

它应该显示我只有两个主要类别，每个都有一个子。在图像，你可以看到我的产品表

Category 1 
    -sub1 
Category 2 
    -sub3 

如果需要一些更多的源或东西我可以提供。

更新配车型：

分类模型

class Categories extends Eloquent { 
    protected $table = 'category'; 
    protected $primaryKey = 'category_id'; 

    public $timestamps = false; 

    public function products() 
    { 
     return $this->hasMany('Product', 'category_id'); 

    } 
    public function subcategories() 
    { 
     return $this->hasMany('SubCategories', 'category_id'); 
    } 
} 

小类模型

class SubCategories extends Eloquent { 
    protected $table = 'sub_category'; 
    protected $primaryKey = 'sub_cat_id'; 

    public $timestamps = false; 

    public function category() 
    { 
     return $this->belongsTo('Category', 'category_id'); 
    } 

    public function products() 
    { 
     return $this->hasMany('Product', 'sub_cat_id'); 
    } 
} 

产品型号

class Product extends Eloquent { 
    protected $table = 'products'; 
    protected $primaryKey = 'product_id'; 

    public function categories() 
    { 
     return $this->hasMany('Categories', 'category_id'); 
    } 

    public $timestamps = false; 
} 

Answer 1

@foreach($categories_menu as $category_menu) 
    @if($category_menu->has('subcategories')) 
     <ul class="nav nav-stacked cat-nav"> 
       <li> 
        <a href="#">{{ $category_menu['category_name'] }} </a> 
         @if($category_menu->subcategories->count()) 
          <ul> 
          @foreach($category_menu->subcategories as $subcategory) 
           @if($subcategory->products->count()) 
           <li class=""><a href="#">{{$subcategory->sub_cat_name}}</a></li> 
           @endif 
          @endforeach 
          </ul> 
         @endif 
       </li> 
      @else 
       <li><a href="#"><i class="fa fa-link"></i> <span>{{ $category_menu->category_name }}</span></a></li> 
      @endif 
     </ul> 
@endforeach 

我添加了一个条件subcatergy要显示，只有当他们的产品计数是在0以上