Accessing hasManyThrough in Blade not working

Your syntax seems off. Second parameter is the table name i believe? Shouldn't it have been requirement_subcategory?

public function categories() {
        return $this->belongsToMany ('App\Category', 'App\Subcategory');
    }

I think your relationships are a bit muddled!

Your Category and Subcategory have a hasMany() <-> belongsTo() relationship.

This requires a category_id field in the Subcategory model. You have a pivot table category_subcategory for them but this is only needed for a ManyToMany relationship.

@acrm

Does a Requirement belong to many Categories?

It belongs to many Subcategories.

Either way, this looks wrong:

public function categories() {
    return $this->belongsToMany ('App\Category', 'App\Subcategory');
}

The second parameter should be the table name (not 'App\Subcategory') but as your table name requirement_subcategory is OK, the second parameter shouldn't be needed.

I've had another look and although there are a few mistakes in your relationships, it's not going to work anyway :-(

Your set up with the pivot table (the belongsToMany relationship between Subcategories and Requirements) won't work with HasThrough methods.

Hi @geordiejackson and @sinnbeck ,

thanks for taking the time. You have been absolutelty right, that I have messed up the relationship between category and subcategory. Now I am referencing with a "category_id" in the subcategories table.

Still, I am not able to retrieve the categories for the chosen subcategory. Is there a way to do that?

best regards acrm

Even trying to do things like that don't work:

@foreach ($subcategories as $subcategory)
  @foreach($subcategory->category as $category)
      <option value="{{ $category->id }}" selected>{{ $category->name }}<option>
   @endforeach
@endforeach

It simply returns

Facade\Ignition\Exceptions\ViewException
Trying to get property 'id' of non-object

Any idea on how to solve it?

Try this and post the output

@foreach ($subcategories as $subcategory)
  @foreach($subcategory->category as $category)
      @dd($category)
   @endforeach
@endforeach

HI @sinnbeck ,

thanks for taking the time to look into my issue. When I paste this into the blade.php and run the site the following code is given as an ouput only in the source code of the generated page:

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</pre>
<script>Sfdump("sf-dump-957772309")</script>

The page is not rendered completely, it stops after this point.

I can just assume that is only wants to dump "true".

Best regards acrm

How go you get $subcategories ?

Right now all seeded, later they might be changed via frontend. Or do you mean sth else?

How do you set that variable in the controller?

$subcategories = Subcategory::all();
$categories = Category::all();
$requirements = Requirement::all();

You really should eager load relationships

$subcategories = Subcategory::with('category')->get();

And you have a belongsTo relationship to category. That means there is only one. So no looping of that :)

@foreach ($subcategories as $subcategory)
  @if($subcategory->category)
      <option value="{{ $subcategory->category->id  }}" selected>{{ $subcategory->category->name }}<option>
   @endif
@endforeach

Thanks, the eager loading did the job :-). Will remember that - I am not doing anything with IT in my main job.