How to call a method of a fragment from adapter class? - kotlin

Question

I have seen many questions like this but they are not the same as my situation and I couldn't use those solutions.
I have a fragment (OrdersByStatusFragment.kt) and the method I want to call from the adapter is getOrderStatusList()
class OrdersByStatusFragment : BaseFragment() {
private lateinit var binding: OrderStatusLayoutBinding
override fun onCreateView(
inflater: LayoutInflater, container: ViewGroup?,
savedInstanceState: Bundle?
): View? {
return inflater.inflate(R.layout.fragment_orders_by_status, container, false)
}
override fun onResume() {
super.onResume()
getOrderStatusList()
}
fun getOrderStatusList() {
showProgressDialog(resources.getString(R.string.please_wait))
FirestoreClass().getOrderStatusList(this#OrdersByStatusFragment)
}
fun successOrderStatusList(orderStatusList: ArrayList<OrderStatus>) {
hideProgressDialog()
if (orderStatusList.size > 0) {
rv_order_by_status.visibility = View.VISIBLE
tv_no_orders_by_status_found.visibility = View.GONE
rv_order_by_status.layoutManager = LinearLayoutManager(activity)
rv_order_by_status.setHasFixedSize(true)
val orderStatusListAdapter =
OrderStatusListAdapter(requireActivity(), orderStatusList)
rv_order_by_status.adapter = orderStatusListAdapter
} else {
rv_order_by_status.visibility = View.GONE
tv_no_orders_by_status_found.visibility = View.VISIBLE
}
}
fun successNewOrderStatus() {
Toast.makeText(requireContext(), "Success", Toast.LENGTH_SHORT).show()
}
}
Adapter OrderStatusListAdapter.kt
open class OrderStatusListAdapter(
private val context: Context,
private var list: ArrayList<OrderStatus>,
) : RecyclerView.Adapter<OrderStatusListAdapter.MyViewHolder>() {
class MyViewHolder(var binding: OrderStatusLayoutBinding) :
RecyclerView.ViewHolder(binding.root)
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): MyViewHolder {
return MyViewHolder(
OrderStatusLayoutBinding.inflate(
LayoutInflater.from(parent.context),
parent,
false
)
)
}
override fun getItemCount(): Int {
return list.size
}
override fun onBindViewHolder(holder: MyViewHolder, position: Int) {
val model = list[position]
if (true) {
GlideLoader(context).loadProductPicture(
model.image,
holder.itemView.iv_order_status_item_image
)
val dateFormat = "dd MMM yyyy HH:mm"
val formatter = SimpleDateFormat(dateFormat, Locale.getDefault())
val calendar: Calendar = Calendar.getInstance()
calendar.timeInMillis = model.order_datetime
val orderDateTime = formatter.format(calendar.time)
holder.itemView.tv_order_status_order_date.text = orderDateTime
holder.itemView.tv_order_status_item_name.text = model.items[0].title
holder.itemView.tv_order_status_item_price.text = "$${model.total_amount}"
holder.itemView.tv_order_status.text = model.order_status
holder.itemView.tv_order_status_order_id.text = model.id
holder.binding.spnOrderChangeStatus.onItemSelectedListener =
object : AdapterView.OnItemSelectedListener {
override fun onItemSelected(
parent: AdapterView<*>?,
view: View?,
position: Int,
id: Long
) {
holder.binding.tvSpinnerValue.text =
parent?.getItemAtPosition(position).toString()
}
override fun onNothingSelected(parent: AdapterView<*>?) {
}
}
holder.binding.btnOrderStatusChangeStatus.setOnClickListener {
Toast.makeText(context, "Button Clicked", Toast.LENGTH_SHORT).show()
FirestoreClass().updateOrderStatus(
model.id,
holder.binding.tvSpinnerValue.text.toString()
)
Toast.makeText(context, "DB Updated", Toast.LENGTH_SHORT).show()
}
holder.itemView.ib_order_status_delete_product.visibility = View.GONE
holder.itemView.setOnClickListener {
val intent = Intent(context, SoldProductDetailsActivity::class.java)
intent.putExtra(Constants.EXTRA_SOLD_PRODUCT_DETAILS, model)
context.startActivity(intent)
}
}
}
}
As you can see the fun getOrderStatusList() in the OrdersByStatusFragment.kt is actually calling a method in the FirestoreClass.kt. Following is the getOrderStatusList() in the FirestoreClass.kt
fun getOrderStatusList(fragment: OrdersByStatusFragment) {
mFireStore.collection(Constants.ORDERS)
.whereIn("order_status", listOf("Pending", "In process"))
.get()
.addOnSuccessListener { document ->
val list: ArrayList<OrderStatus> = ArrayList()
for (i in document.documents) {
val orderStatus = i.toObject(OrderStatus::class.java)!!
orderStatus.id = i.id
list.add(orderStatus)
}
fragment.successOrderStatusList(list)
}
.addOnFailureListener {
fragment.hideProgressDialog()
}
}

Answer 1

The way I solved something like this is to pass a reference to the method into the adapter's constructor, then you can call the method in the adapter.
See kotlin-how-to-pass-a-function-as-parameter-to-another
In general, the link shows a class containing a method called buz.
Let's say your adapter has a constructor like:
class MyAdapter (private val context: Context, val buzz: () -> Unit) : RecyclerView.Adapter<RecyclerView.ViewHolder>()
then you can create the adapter like
MyAdapter(applicationContext, ::buz)
In the adapter the method can be called normally:
buzz()