test_app/app/Models/Activity.php

<?php

namespace App\Models;

use Illuminate\Database\Eloquent\Model;
use Illuminate\Database\Eloquent\SoftDeletes;

class Activity extends Model
{
    use SoftDeletes;
    protected $table='activity';

    protected $fillable = ['title','start_time','end_time','big_gift','honor_wall','is_ing','super_up','top_down','top_up','crown_down','contents','disabled'];

    public function gift()
    {
        return $this->hasMany('App\Models\Gifts','activity_id','id');
    }
}