surveyor_indonesia_backend/app/Models/AssignMaterial.php

<?php

namespace App\Models;

use Illuminate\Database\Eloquent\Model;
use App\Models\{Activity,RequestMaterial,ReportActivityMaterial};
use Illuminate\Support\Facades\DB;
class AssignMaterial extends Model
{
    protected $table = 'assign_material_to_activity';

    const CREATED_AT = 'created_at';
    const UPDATED_AT = 'updated_at';

    protected $fillable = [
		'proyek_id', 'activity_id', 'material_id', 'qty_planning',
		'budget', 'plan_date', 'status_activity', 'type',
		'created_at', 'created_by', 'updated_at', 'updated_by'
	];

	protected $casts = [
        'id' => 'integer',
        'budget' => 'string',
        'qty_planning' => 'float'
    ];

	public static function boot() {
		parent::boot();
        DB::transaction(function () {
            static::created(function($data) {
                $activity = Activity::find((int)$data->activity_id);
                $material = RequestMaterial::find((int)$data->material_id);
                $activity->rencana_biaya += (doubleval($material->price) * doubleval($data->qty_planning));
                $activity->save();
            });

            static::deleted(function($data) {
                ReportActivityMaterial::where('assign_material_id', $data->id)->delete();
                $activity = Activity::find($data->activity_id);
                $activity->rencana_biaya -= (doubleval($data->budget) * doubleval($data->qty_planning));
                $activity->save();
            });
        }, 5);
	}
}