How to send data from fragment a to fragment B then add this data to the recylcerview?

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Android

Kotlin

here is my scenario I have 2 fragment A, A consists of recyclerView Adapter to display list of items, and fragment B has 4 edit texts, and an add button, when the user clicks on add button it will navigate back to fragment A, here I'm confused how do i bind the Args from fragment B and add them to the recyclerView as a new item.

here is my code

class ContactListFragment : Fragment() { //Fragment A 

    private var _binding: FragmentContactListBinding? = null
    private val binding get() = _binding!!

    private   var adapter: ListAdapter? = null

    private  var listOfStudents: MutableList<StudentInfo>? = null

//    private val sharedViewModel: SharedViewModel by viewModels()



    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        arguments?.let {

        }
    }

    override fun onCreateView(
        inflater: LayoutInflater, container: ViewGroup?,
        savedInstanceState: Bundle?
    ): View {
        //Inflate the layout

        _binding = FragmentContactListBinding.inflate(layoutInflater)

        return binding.root
    }

    override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
        super.onViewCreated(view, savedInstanceState)
//i tried this but it didn't work
//        loadStudents()

        adapter = ListAdapter(mutableListOf(),requireContext())

        binding.rvListContact.adapter = adapter



        binding.fabAddItem.setOnClickListener {
            val action =
                ContactListFragmentDirections
                    .actionContactListFragmentToAddItemFragment()
            it.findNavController().navigate(action)

        }




    }

    /**
     * here i tired to make this function to add a new item to the list with new args,
     * but it didn't work
     */

//    private fun loadStudents(){
//
//        val name = ContactListFragmentArgs.fromBundle(requireArguments()).studentName
//        val number = ContactListFragmentArgs.fromBundle(requireArguments()).studentNumber
//        val country = ContactListFragmentArgs.fromBundle(requireArguments()).studentCountry
//
//
//        listOfStudents = mutableListOf(
//            StudentInfo(
//                name,
//                number,
//                country
//            )
//        )
//
//
//
//    }

    override fun onDestroyView() {
        super.onDestroyView()
        _binding = null
    }

}

AddItemFragment.kt

<pre>class AddItemFragment : Fragment() {//Fragment B

    private var _binding: FragmentAddItemBinding? = null
    private val binding get() = _binding!!

 


    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        arguments?.let {

        }
    }

    override fun onCreateView(
        inflater: LayoutInflater, container: ViewGroup?,
        savedInstanceState: Bundle?
    ): View {

        _binding = FragmentAddItemBinding.inflate(layoutInflater)

        return binding.root

    }

    override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
        super.onViewCreated(view, savedInstanceState)





        binding.apply {

            /** Navigate from [AddItemFragment],
             *  To [AddItemFragment], only if the condition is true.
             * */
            btnAddNewContact.setOnClickListener {

                /* if name/phoneNumber field is empty it will give an error,
                 and return when clicking on ADD button,
                 and it will not navigate back to the screen.
                 */
                if (edAddName.text!!.isEmpty()) {
                    edAddName.error = "name is required!"
                   toastMessage("missing required fields!")
                    return@setOnClickListener
                }
                if (edAddPhoneNumber.text!!.isEmpty()) {
                    edAddPhoneNumber.error = "phone number is required"
                   toastMessage("missing required fields!")
                    return@setOnClickListener
                }

                if (edCountry.text!!.isEmpty()) {
                    edCountry.error = "country is required"
                 toastMessage("missing required fields!")
                    return@setOnClickListener
                }

                 val studentName = binding.edAddName.text.toString()
                 val studentNumber = binding.edAddPhoneNumber.text.toString()
                 val studentCountry = binding.edCountry.text.toString()

                val student = StudentInfo(studentName,studentNumber,studentCountry)

                findNavController().navigate(
                    AddItemFragmentDirections.actionAddItemFragmentToContactListFragment(
                        studentName,
                        studentNumber,
                        studentCountry,
                    )
                )
//                listAdapter?.addStudentCard(mutableListOf<StudentInfo>().add(student))
            }

            //Dialog to alert if the user is sure to cancel.
            val alertDialog = AlertDialog.Builder(requireContext())
                .setTitle("CANCEL DIALOG")
                .setMessage("Do you want to cancel adding new card o your list?")
                .setPositiveButton("YES"){_,_ ->
                    //if user clicks yes then navigate back to the [ContactListFragment]
                    findNavController().navigate(
                        AddItemFragmentDirections.actionAddItemFragmentToContactListFragment())
                toastMessage("adding new contact is cancelled!")
                }

                .setNegativeButton("DISMISS"){dialogInterface,_ ->
                    dialogInterface.dismiss()
                }.create()

            btnCancel.setOnClickListener {

                //if fields are empty then the condition is true,
                //if it is true then navigate back to the ContactListFragment.
                if (edAddPhoneNumber.text!!.isEmpty() && (edAddName.text!!.isEmpty())){
                    findNavController().navigate(
                        AddItemFragmentDirections.actionAddItemFragmentToContactListFragment()
                    )
                   toastMessage("adding new contact is cancelled!")
                }
                //if the user clicks on cancel Button,and texts fields is not empty then show the dialog.
                 if(edAddPhoneNumber.text!!.isNotEmpty() && (edAddName.text!!.isNotEmpty())){
                    alertDialog.show()
                }
            }

        }
    }
    //function represents toast message.
    fun toastMessage(text: String) {
        Toast.makeText(context, text, Toast.LENGTH_SHORT).show()
    }


}

RecylcerViewAdaptyer.kt

class ListAdapter(private var studentInfo: MutableList<StudentInfo>, private val context: Context): RecyclerView.Adapter<ListAdapter.ItemViewHolder>(){


    inner class ItemViewHolder(val binding: ItemViewBinding): RecyclerView.ViewHolder(binding.root)

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

        val binding = ItemViewBinding.inflate(LayoutInflater.from(parent.context), parent,false)

        return ItemViewHolder(binding)
    }




    override fun onBindViewHolder(holder: ItemViewHolder, position: Int) {
        val currItem = studentInfo[position]
        holder.binding.apply {
            tvName.text = currItem.name
            tvNumber.text = currItem.number
            tvCountry.text = currItem.country
        }

    }

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



}

What I have tried:

I created new function to add the item to the list in the Adapter, and notify it when new item is inserted, and i called the function in Fragment A and passed in the args.

<pre>   
    fun addStudent(studentCard: StudentInfo){
       studentInfo.add(studentCard)
        notifyItemInserted(studentInfo.size - 1)
    }