ViewGroup будет нулевым, когда вернется из другого фрагмента, который мы вызываем из текущего фрагмента в компоненте навигации android

Question

Я использовал компонент навигации в своем приложении. в одном из моих фрагментов (назовем его FragmentA) у меня много полей. и в этом фрагменте я определяю группу радиосвязи для видимых / исчезнувших в некоторых полях. все работает отлично, когда я перешел из HomeFragment во FragmentA, но когда я go из FragmentA в другое место назначения, которое тоже является фрагментом (и давайте назовем его, например, FragmentB) и обработал все это с помощью компонента навигации, а затем попытался снова FragmentA, я получил нулевой указатель для группы просмотра как unknown Source с этим сообщением: Parameter specified as non-null is null. и это мой код для обработки полей Visible / Gone.

  private fun showChildren(v: View, isShow: Boolean) {

    val viewGroup = v as ViewGroup
    for (i in 0 until viewGroup.childCount) {
        val v1 = viewGroup.getChildAt(i)
        (v1 as? ViewGroup)?.let { showChildren(it, isShow) }

        if (v1.tag == "check_for_visibility" && isShow) {
            v1.visibility = View.VISIBLE
        } else if (v1.tag == "check_for_visibility" && !isShow) {
            v1.visibility = View.GONE
        }
    }
}

, пожалуйста, расскажите мне, как я могу обработать это исключение нулевого указателя с помощью ViewGroup при возвращении из FragmentB в FragmentA?

edit:

import android.content.Intent
import android.speech.RecognizerIntent
import android.view.View
import android.view.ViewGroup
import android.widget.AdapterView
import android.widget.AdapterView.OnItemSelectedListener
import android.widget.ArrayAdapter
import androidx.core.content.ContextCompat
import androidx.lifecycle.Observer
import androidx.navigation.fragment.findNavController



class AddPickupContinuousParentFragment :
    BaseFragment<FragmentAddPickupContinuousParentBinding, AddPickupContinuousParentViewModel>(
        R.layout.fragment_add_pickup_continuous_parent,
        AddPickupContinuousParentViewModel()
    ) {

    private var kindOfRentList: ArrayList<String> = arrayListOf()
    private var selectedRent = ""

    override fun initVariables() {
        binding.addPickupContinuousParentViewModel = vModel
    }

    override fun initObserves() {

    }

    override fun initViews() {

        val receivedWaybill =
            arguments?.let { AddPickupContinuousParentFragmentArgs.fromBundle(it).waybill }
        val receivedClosedArray =
            arguments?.let { AddPickupContinuousParentFragmentArgs.fromBundle(it).closedArray }

        if (receivedWaybill != null && receivedWaybill != "0") {
            if (receivedWaybill.isNotEmpty()) {

                binding.layoutCargo.etNewPickupWaybill.isEnabled = false
                binding.layoutCargo.etNewPickupWaybill.setText(receivedWaybill)
            }
        }

        if (receivedClosedArray != null) {
            if (receivedClosedArray.isNotEmpty()) {
                binding.layoutCargo.etNewPickupClosedCount.isEnabled = false
                binding.layoutCargo.etNewPickupClosedCount.setText(receivedClosedArray.size.toString())
            }
        }


        val countries: Array<out String> = resources.getStringArray(R.array.countries_array)
        ArrayAdapter(
            requireContext(),
            android.R.layout.simple_list_item_1,
            countries
        ).also {
            binding.layoutSender.autoAddSenderStateCity.setAdapter(it)
            binding.layoutReceiver.autoAddReceiverStateCity.setAdapter(it)


        // spinner init
        kindOfRentList.add("test1")
        kindOfRentList.add("test2")
        val kindOfRentAdapter =
            ArrayAdapter(requireContext(), android.R.layout.simple_spinner_item, kindOfRentList)
        kindOfRentAdapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item)
        binding.layoutCargo.spinnerNewPickupKindRent.adapter =
            kindOfRentAdapter
        selectedRent = kindOfRentList[0]

        binding.layoutCargo.spinnerNewPickupKindRent.onItemSelectedListener =
            object : OnItemSelectedListener {
                override fun onItemSelected(
                    parent: AdapterView<*>,
                    view: View,
                    position: Int,
                    id: Long
                ) {
                    selectedRent =
                        binding.layoutCargo.spinnerNewPickupKindRent.selectedItem.toString()
                }

                override fun onNothingSelected(parent: AdapterView<*>?) {}
            }

        // visible or gone fields
        vModel.editTextVisibility.observe(
            viewLifecycleOwner,
            Observer {
                if (it == true) {

                    binding.radioNewPickupNo.setTextColor(
                        ContextCompat.getColor(
                            requireContext(),
                            R.color.red
                        )
                    )
                    binding.radioNewPickupYes.setTextColor(
                        ContextCompat.getColor(
                            requireContext(),
                            R.color.lightGray
                        )
                    )

                    activity?.window?.decorView?.let { it1 ->
                        showChildren(it1, true)
                    }
                } else {

                    binding.radioNewPickupNo.setTextColor(
                        ContextCompat.getColor(
                            requireContext(),
                            R.color.lightGray
                        )
                    )
                    binding.radioNewPickupYes.setTextColor(
                        ContextCompat.getColor(
                            requireContext(),
                            R.color.green
                        )
                    )

                    activity?.window?.decorView?.let { it1 -> showChildren(it1, false) }
                }
            })


        val intent = Intent(RecognizerIntent.ACTION_RECOGNIZE_SPEECH)
        intent.putExtra(RecognizerIntent.EXTRA_LANGUAGE, "fa");

        binding.layoutSender.imgAddSenderName.setOnClickListener {

            startActivityForResult(intent, 700)
        }

        binding.layoutSender.imgAddSenderAddress.setOnClickListener {

            startActivityForResult(intent, 701)
        }

        binding.layoutSender.imgAddSenderCompany.setOnClickListener {

            startActivityForResult(intent, 702)
        }

        binding.layoutReceiver.imgAddReceiverName.setOnClickListener {

            startActivityForResult(intent, 703)
        }

        binding.layoutReceiver.imgAddReceiverAddress.setOnClickListener {

            startActivityForResult(intent, 704)
        }

        binding.layoutReceiver.imgAddReceiverCompany.setOnClickListener {

            startActivityForResult(intent, 705)
        }

        binding.btnAddPickupRegister.setOnClickListener {
            findNavController().navigate(R.id.action_addPickupContinuousParentFragment_to_finalizeCargoFragment)
        }

    }


    override fun onActivityResult(
        requestCode: Int,
        resultCode: Int,
        data: Intent?
    ) {

        when (requestCode) {

            700 -> {
                try {
                    if (data != null) {
                        val result: String? = data.getStringArrayListExtra(
                            RecognizerIntent.EXTRA_RESULTS
                        )[0]

                        binding.layoutSender.etAddSenderName.setText(result)
                    }
                } catch (e: Exception) {
                    e.printStackTrace()
                }
            }

            701 -> {
                try {
                    if (data != null) {
                        val result: String? = data.getStringArrayListExtra(
                            RecognizerIntent.EXTRA_RESULTS
                        )[0]

                        binding.layoutSender.etAddSenderAddress.setText(result)
                    }
                } catch (e: Exception) {
                    e.printStackTrace()
                }
            }

            702 -> {
                try {
                    if (data != null) {
                        val result: String? = data.getStringArrayListExtra(
                            RecognizerIntent.EXTRA_RESULTS
                        )[0]

                        binding.layoutSender.etAddSenderCompany.setText(result)
                    }
                } catch (e: Exception) {
                    e.printStackTrace()
                }
            }

            703 -> {
                try {
                    if (data != null) {
                        val result: String? = data.getStringArrayListExtra(
                            RecognizerIntent.EXTRA_RESULTS
                        )[0]

                        binding.layoutReceiver.etAddReceiverName.setText(result)
                    }
                } catch (e: Exception) {
                    e.printStackTrace()
                }
            }

            704 -> {
                try {
                    if (data != null) {
                        val result: String? = data.getStringArrayListExtra(
                            RecognizerIntent.EXTRA_RESULTS
                        )[0]

                        binding.layoutReceiver.etAddReceiverAddress.setText(result)
                    }
                } catch (e: Exception) {
                    e.printStackTrace()
                }
            }

            705 -> {
                try {
                    if (data != null) {
                        val result: String? = data.getStringArrayListExtra(
                            RecognizerIntent.EXTRA_RESULTS
                        )[0]

                        binding.layoutReceiver.etAddReceiverCompany.setText(result)
                    }
                } catch (e: Exception) {
                    e.printStackTrace()
                }
            }
        }
    }


    private fun showChildren(v: View, isShow: Boolean) {

        try {
            val viewGroup = v as ViewGroup
            for (i in 0 until viewGroup.childCount) {
                val v1 = viewGroup.getChildAt(i)
                (v1 as? ViewGroup)?.let { showChildren(it, isShow) }

                if (v1.tag == "check_for_visibility" && isShow) {
                    v1.visibility = View.VISIBLE
                } else if (v1.tag == "check_for_visibility" && !isShow) {
                    v1.visibility = View.GONE
                }
            }
        } catch (e: Exception) {
            e.printStackTrace()
        }

    }
}