Blank object in Eloquent belongsTo() - laravel

Question

I'm trying to display which one attribute (code) of Item. ServiceItem has Item as a foreign key. But I can't get the Item at all.
This one gives a blank object in blade template:
#foreach ($service->serviceItems as $serviceItem )
{{ json_encode($serviceItem->item()) }}
#endforeach
Here's my model declaration:
//ServiceItem model
class ServiceItem extends Model
{
use HasFactory;
public $fillable = ['service_id', 'item_id', 'values'];
public function service()
{
return $this->belongsTo(Service::class, 'foreign_key');
}
// this doesn't work
public function item()
{
return $this->belongsTo(Item::class, 'foreign_key');
}
}
// Service model
class Service extends Model
{
use HasFactory;
public $fillable = ['user_id', 'site_id', 'title', 'status', 'remarks', 'report', 'date'];
public function user()
{
return $this->belongsTo('\App\Models\User');
}
public function site()
{
return $this->belongsTo('\App\Models\Site');
}
public function serviceItems() {
return $this->hasMany('\App\Models\ServiceItem');
}
}
This is my controller:
public function index()
{
$services = Service::latest()->paginate(5);
return view('services.index', compact('services'))
->with('i', (request()->input('page', 1) - 1) * 5);
}
Please help me to display the code attribute in Item from Service!!! Thanks a lot!

Answer 1

I suppose you read the Laravel doc of model relationship definition. They referenced to put foreign key as the second parameter, not the foreign_key as word but your actual foreign key that reference the parent table. you have to change the model code.
class ServiceItem extends Model
{
use HasFactory;
public $fillable = ['service_id', 'item_id', 'values'];
public function service()
{
return $this->belongsTo(Service::class, 'service_id');
}
public function item()
{
return $this->belongsTo(Item::class, 'item_id');
}
}
and then $serviceItem->item should work as expected.