Kotlin Android JSON解析，对RecyclerView进行了改造

Question

我正在尝试从网址https://api.sr.se/api/v2/channels/?format=json解析json数据，并显示对Recyclerview的json响应。但是在Recyclerview中没有任何显示，我认为我对基本URL的调用是错误的。我要显示的是所有频道的名称和ID，然后前进到现在在每个频道中播放的那首歌。
有人可以帮我吗？

代码：

    data class Complete(
            @SerializedName("channels")
            val channels: List<Channel>,
            @SerializedName("copyright")
            val copyright: String,
            @SerializedName("pagination")
            val pagination: Pagination
    )
    data class Channel(
            @SerializedName("channeltype")
            val channeltype: String,
            @SerializedName("color")
            val color: String,
            @SerializedName("id")
            val id: Int,
            @SerializedName("image")
            val image: String,
            @SerializedName("imagetemplate")
            val imagetemplate: String,
            @SerializedName("liveaudio")
            val liveaudio: Liveaudio,
            @SerializedName("name")
            val name: String,
            @SerializedName("scheduleurl")
            val scheduleurl: String,
            @SerializedName("siteurl")
            val siteurl: String,
            @SerializedName("tagline")
            val tagline: String,
            @SerializedName("xmltvid")
            val xmltvid: String
    )

    class RadioItemAdapter(val postList: List<Channel>, val context: Context) :
           RecyclerView.Adapter<RadioItemAdapter.ViewHolder> (){

        override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): ViewHolder {

            return ViewHolder(LayoutInflater.from(context).inflate(R.layout.radio_item_layout,
                    parent, false))
        }

        override fun getItemCount(): Int {
            return 10
        }

        override fun onBindViewHolder(holder: ViewHolder, position: Int) {

            holder.itemView.txtPostTitle.text = postList.get(position).id.toString()
            holder.itemView.txtPostBody.text = postList.get(position).toString()

        }


        class ViewHolder(view: View) : RecyclerView.ViewHolder(view)

    }
    interface Network {
    @GET("api/v2/channels/?format=json")
    fun getAllRadio(): Observable<List<Channel>>
}

    class MainActivity : AppCompatActivity() {

        override fun onCreate(savedInstanceState: Bundle?) {
            super.onCreate(savedInstanceState)
            setContentView(R.layout.activity_main)
            rv__list_posts.layoutManager = LinearLayoutManager(this)

            val retrofit = Retrofit.Builder().addConverterFactory(GsonConverterFactory.create(GsonBuilder().create()))
                    .addCallAdapterFactory(RxJava2CallAdapterFactory.create())
                    .baseUrl("https://api.sr.se/").build()

            val postsApi = retrofit.create(Network::class.java)

            var response = postsApi.getAllRadio()

            response.observeOn(AndroidSchedulers.mainThread()).subscribeOn(IoScheduler()).subscribe {
                rv__list_posts.adapter = RadioItemAdapter(it,this)
            }
        }
    }