I can't view my data from api in recyclerview-CodePudding

I can't view my data from api in recyclerview. Can you help me what is the problem?

MyCode:

Adapter:

class NewsAdapter(private val data: List<AllData>) :
    RecyclerView.Adapter<NewsAdapter.MyViewHolder>() {

    class MyViewHolder(view: View) : RecyclerView.ViewHolder(view) {
            val title = view.findViewById<TextView>(R.id.news_info)
            val imageView = view.findViewById<ImageView>(R.id.news_img)
    }

    override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): MyViewHolder {
        val view = LayoutInflater.from(parent.context)
            .inflate(R.layout.main_activity_cardview_card_menu, parent, false)
        return MyViewHolder(view)
    }

    override fun onBindViewHolder(holder: MyViewHolder, position: Int) {
        val news:AllData=data[position]
        holder.title.text = news.haberler[position].title
        Glide.with(holder.imageView.context).load(news.haberler[position].imageUrl).into(holder.imageView)
    }

    override fun getItemCount(): Int {
        return data.size
    }

}

activity_main.xml

<androidx.recyclerview.widget.RecyclerView
        android:id="@ id/news_recyclerView"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="32dp"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.0"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@ id/view" />

MainActivity:

class MainActivity : AppCompatActivity() {

    private  val itemList = ArrayList<MenuCardModel>()
    private lateinit var menuCardAdapter: MenuCardAdapter
    
    private lateinit var newsAdapter: NewsAdapter

    val data = ArrayList<AllData>()

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)


        loadNews()
    }

    private fun loadNews() {

            val retrofit = Retrofit.Builder()
                .baseUrl(BASE_URL)
                .addConverterFactory(GsonConverterFactory.create())
                .build()
    
            val service = retrofit.create(ApiInterface::class.java)
            val call = service.getNews()

        call.enqueue(object :Callback<AllData>{
            override fun onResponse(
                call: Call<AllData>,
                response: Response<AllData>
            ) {
                   response.body()?.let {
                       data.add(it)
                           newsAdapter = NewsAdapter(data)
                           news_recyclerView.adapter = newsAdapter

                   }
            }

            override fun onFailure(call: Call<AllData>, t: Throwable) {
                t.printStackTrace()
            }

        })

    }

}

Model :

data class Haberler(
    val content: String,
    val id: Int,
    val imageUrl: String,
    val orderNo: Int,
    val parentId: Any,
    val title: String,
    val videoUrl: String
)

AllData :

data class AllData(
    val haberler: List<Haberler>,
    val istatistik: Istatistik,
    val konferans: Konferans,
    val kvkk: String,
    val liveChat: String,
    val pratikBilgiler: List<PratikBilgiler>,
    val sgkTv: List<SgkTv>,
    val sss: List<Ss>,
    val state: Boolean,
    val subjects: List<Subject>
)

Hello, I can't view my data from api in recyclerview. Can you help me what is the problem?

CodePudding user response：

It looks like you forgot to set layout manager to your recyclerview before you set adapter

There are two ways you can set layout manager

First way by xml

<androidx.recyclerview.widget.RecyclerView
    app:layoutManager="androidx.recyclerview.widget.LinearLayoutManager"
    ...
    />

second way is by code

newsAdapter = NewsAdapter(data)
news_recyclerView.layoutManager = LinearLayoutManager(context) // line which you forgot
news_recyclerView.adapter = newsAdapter

for more understanding about layout managers , you can refer below links

https://developer.android.com/reference/androidx/recyclerview/widget/RecyclerView.LayoutManager

CodePudding user response：

Just add layoutManager this line in RecyclerView as follow:

<androidx.recyclerview.widget.RecyclerView
    app:layoutManager="androidx.recyclerview.widget.LinearLayoutManager"
    ...
    />

You are missing layout manager for recycler view