解決したいこと

Laravel6においてレシピアプリを開発中です。
フォームは動的に増え、1つのレシピ(recipes)に対して何個でも材料(materials)を登録できるようにしたいです。

ご教授お願いいたします。

該当するソースコード

RecipeController.php

public function store(RecipeRequest $request)
    {
     
        $recipe = Recipe::create(
            [
                'user_id' => auth()->id(),
                'name' => $request->name,
                'category_id' => $request->category_id,
                'image' => $path,
                'process' => $request->process,
            ]);
            
            
         $recipe->materials()->createMany([
          [
              'name' => $request->input('material_name.*'),
              'recipe_id' => $recipe->id,
              'amount' => $request->input('amount.*'),
              'unit' => $request->input('unit.*'),
            ],
        ]);

create.php

<div class="form-group">
        <label>材料
            <input class="form-control" type="hidden" name="recipe_id" value="">
            <div class="materials">
            <input class="form-control" type="name" name="material_name[]" placeholder="材料名">
            <input class="form-control" name="amount[]" placeholder="分量">
            <select class="form-control" name="unit[]">
                @foreach($units as $unit)
                 <option value="{{ $unit->name }}">{{ $unit->name }}</option>
                @endforeach
            </select>    
            <input type="button" value="＋" class="add pluralBtn">
            <input type="button" value="－" class="del pluralBtn">
           
            </div>
        </label>
    </div>

Material.php

<?php

namespace App;

use Illuminate\Database\Eloquent\Model;

class Material extends Model
{
    protected $fillable = [
        'name','recipe_id','amount','unit',  
    ];
    
    public function recipe()
    {
        return $this->belongsTo('App/Recipe');
    }
    
    public function unit()
    {
        return $this->hasOne('App/Unit');
    }
}

materials.table.php

 public function up()
    {
        Schema::create('materials', function (Blueprint $table) {
            $table->bigIncrements('id');
            $table->unsignedBigInteger('recipe_id');
            $table->string('name');
            $table->string('amount');
            $table->string('unit');
            $table->timestamps();
            
            $table->foreign('recipe_id')->references('id')->on('recipes')->onDelete('cascade');
        });
    }