类别、子类别和使用 Laravel 发布

如何解决类别、子类别和使用 Laravel 发布

我正在尝试创建帖子、类别和子类别，但我不知道如何编写

我认为这是不正确的，因为当我想在带有数据库的帖子表中插入一条记录，并想添加 category_id 时，我看到了所有类别，但我只想查看子类别并选择它们。

这是我的数据库：

类别迁移：

 public function up()
    {

        Schema::dropIfExists('categories');
        Schema::create('categories',function (Blueprint $table) {
            $table->id();
            $table->unsignedBigInteger('parent_id')->nullable();

            $table->string('title');
            $table->longText('description');
            $table->tinyinteger('status')->comment('status is 1 when a category is active and it is 0 otherwise.')->nullable();


            $table->rememberToken();
            $table->softDeletes();
            $table->timestamps();

        });
    }

这是我的迁移后：

public function up()
    {
        Schema::create('posts',function (Blueprint $table) {
            $table->id();
            $table->unsignedBigInteger('category_id');
            $table->unsignedBigInteger('user_id');

            $table->string('title');
            $table->string('short_description');
            $table->longText('long_description');
            $table->longText('picture');
            $table->string('study_time');
            $table->integer('likes')->nullable();
            $table->tinyinteger('status')->nullable()->comment('status is 1 when a post is active and it is 0 otherwise.')->nullable();

            $table->foreign('category_id')->references('id')->on('categories');
            $table->foreign('user_id')->references('id')->on('posts');

            $table->rememberToken();
            $table->softDeletes();
            $table->timestamps();
        });
    }

和我的类别模型：

class Category extends Model
{
    use HasFactory;

    protected $fillable = [
         'parent_id','title','description','status',];

    public function children(){
        return $this->hasMany(Category::class,'parent_id');
    }



    public function post(){
        return $this->hasMany(Post::class);
    }
}

和我的帖子模型

class Post extends Model
{
    use HasFactory;

    protected $fillable = [
        'user_id','category_id','short_description','long_description','picture','study_time','likes',];

    public function category(){
        return $this->belongsTo(Category::class);
    }


    public function user(){
        return $this->belongsTo(User::class);
    }
}

我该怎么办？