這個錯誤發生在我身上 E/RecyclerView: No adapter attached; 跳過布局

Question

我知道我的layoutManager管理器和adapter似乎是 null，但我不太明白為什么是 null。

這是我的GpsFragment.kt的代碼

class GpsFragment : Fragment() {

override fun onCreateView(
    inflater: LayoutInflater,
    container: ViewGroup?,
    savedInstanceState: Bundle?
): View? {
    (context as AppCompatActivity).supportActionBar!!.title = "Gps"
    val root = inflater.inflate(R.layout.fragment_gps, container, false)

        showCars()

    return root
}

private fun showCars(){
    val cars = listOf(
        Cars("Bezza","0.17263","3.267834"),
        Cars("Bezza","0.17263","3.267834"),
        Cars("Bezza","0.17263","3.267834"),
        Cars("Bezza","0.17263","3.267834")
    )

    myCarlist?.layoutManager = LinearLayoutManager(activity)
    myCarlist?.adapter = CarAdapter(cars)
}

這是我的 model class Cars.kt的代碼

data class Cars(val name: String = "-",
            val latitude: String = "-",
            val longtitude: String = "-")

這是我的適配器CarAdapter.kt的代碼

class CarAdapter (private val cars : List<Cars>) : RecyclerView.Adapter<CarAdapter.CarViewHolder>(){

override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): CarViewHolder {
    val inflater = LayoutInflater.from(parent.context).inflate(R.layout.list_layout, parent, false)

    return  CarViewHolder(inflater)
}

override fun getItemCount() = cars.size

override fun onBindViewHolder(holder: CarViewHolder, position: Int) {
    val car = cars[position]

    holder.view.carname.text = car.name
    holder.view.latitude.text = car.latitude
    holder.view.longtitude.text = car.longtitude

}

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

}

Answer 1

嘗試在onViewCreated oncreateView中調用你的方法showcars()因為

Fragment.onCreateView() 的文檔現在說：

建議只在該方法中擴充布局，將對返回View進行操作的邏輯移至onViewCreated(View, Bundle)。