我有一个活动,我试图从API中获取数据,并在那里显示列表,但我无法在 adapter .

代码

MainActivity.kt

override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)
        
        categories.layoutManager = LinearLayoutManager(this)
        categories.adapter = CategoriesAdapter(//what should be here?)
    }
    
    // api code
    private fun callAPIDemo(textView: TextView) {
        // Instantiate the RequestQueue.
        val queue = Volley.newRequestQueue(this)
        val url = "https://example.com/api/isp/categories"
        // Request a string response from the provided URL.
        val stringRequest = StringRequest(
            Request.Method.GET, url,
            Response.Listener<String> { response ->
                val jsonArray = JSONArray(response)
                val list: MutableList<Category> = ArrayList()
                for (i in 0 until jsonArray.length()) {
                    val jsonObject = jsonArray.getJSONObject(i)
                    list.add(parseData(jsonObject))
                }
                // here you will have the complete list of data in your "list" variable
            },
            Response.ErrorListener { textView.text = "That didn't work!" })
        // Add the request to the RequestQueue.
        queue.add(stringRequest)
    }
    // parsing data
    private fun parseData(jsonObject: JSONObject): Category {
        var listingObject = Category(
            jsonObject.getString("name"),
            jsonObject.getString("slug"),
            jsonObject.getString("image")
        )
        return listingObject
    }
    //

CategoriesAdapter.kt

class CategoriesAdapter(val categories : ArrayList<Category>) : RecyclerView.Adapter<CategoriesAdapter.ViewHolder>() {

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

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

    override fun onBindViewHolder(holder: ViewHolder, position: Int) {
        holder.textView.text = categories.get(position).name
        holder.textViewSlug.text = categories.get(position).slug

        //hardcoding the image, just for simplicity, you can set this also from data list same as above
        //holder.aImage.setImageResource(R.mipmap.ic_launcher)

        //here is the image setup by using glide
        Glide.with(holder.aImage.context).load(categories.get(position).image).into(holder.aImage)
    }


    class ViewHolder(itemView: View) : RecyclerView.ViewHolder(itemView) {
        var textView: TextView
        var textViewSlug: TextView
        var aImage: ImageView

        init {
            textViewSlug = itemView.findViewById(R.id.text_slug)
            textView = itemView.findViewById(R.id.text_name)
            aImage = itemView.findViewById(R.id.a_image)

        }
    }

}

Category.kt

data class Category(
    val name: String,
    val slug: String,
    val image: String
)

activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity">

    <androidx.recyclerview.widget.RecyclerView
        android:id="@+id/categories"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        tools:layout_editor_absoluteX="1dp"
        tools:layout_editor_absoluteY="1dp" />
</androidx.constraintlayout.widget.ConstraintLayout>

categries_row.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:orientation="vertical"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <ImageView
        android:id="@+id/a_image"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        android:layout_width="80dp"
        android:layout_height="80dp"
        android:contentDescription="@string/image" />

    <TextView
        android:id="@+id/text_name"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginStart="20dp"
        android:layout_marginEnd="20dp"
        android:textSize="18sp"
        app:layout_constraintBottom_toBottomOf="@+id/a_image"
        app:layout_constraintStart_toEndOf="@+id/a_image"
        app:layout_constraintTop_toTopOf="@+id/a_image" />


    <TextView
        android:id="@+id/text_slug"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginStart="20dp"
        android:layout_marginEnd="20dp"
        android:textSize="18sp"
        app:layout_constraintBottom_toBottomOf="@+id/text_name"
        app:layout_constraintStart_toEndOf="@+id/text_name"
        app:layout_constraintTop_toTopOf="@+id/text_name" />

</LinearLayout>

我应该放什么 categories.adapter = CategoriesAdapter(//what should be here?) 主要活动.kt