Unresolved reference: myViewHolder after switching to View Binding - kotlin

Question

After switching from removing kotlin_extensions and switching to view binding, I received a "Unresolved reference: myViewHolder" in my onBindViewHolder method and when I replace "myViewHolder" with "holder", it then gives me a "Unresolved reference: bind". How do I resolve this.
MyAdapter
class MyAdapter(private val context: Context, private val mHelper : TaskDbHelper) : RecyclerView.Adapter<MyAdapter.MyViewHolder>(),
SwipeAndDragHelper.ActionCompletionContract {
class MyViewHolder(val binding: CellCardsBinding): RecyclerView.ViewHolder(binding.root ) {
fun binding() {
}
}
private var touchHelper: ItemTouchHelper? = null
private var list = mutableListOf<MyObject>()
override fun onAttachedToRecyclerView(recyclerView: RecyclerView) {
initList()
super.onAttachedToRecyclerView(recyclerView)
}
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): MyViewHolder {
return MyViewHolder(CellCardsBinding.inflate(LayoutInflater.from(parent.context), parent, false))
}
#RequiresApi(Build.VERSION_CODES.P)
#SuppressLint("ClickableViewAccessibility")
override fun onBindViewHolder(holder: MyViewHolder, position: Int) {
val myObject = list[position]
myViewHolder.bind(myObject)
val activity: Activity = context as Activity
holder.binding.text.setOnClickListener{
activity.launchActivity<AddNoteActivity>(42) {
putExtra("PositionInList", position.toString())
putExtra("TaskTitle", myObject.title)
putExtra("TaskText", myObject.text)
}
}
activity.findViewById<RecyclerView>(R.id.recyclerView).setOnTouchListener { _, event ->
when (event.actionMasked) {
MotionEvent.ACTION_UP -> {
updateNotesPositionInDb()
false
}
else -> {
false
}
}
}
holder.binding.title.setOnTouchListener { _, event ->
when (event.actionMasked) {
MotionEvent.ACTION_DOWN -> {
touchHelper!!.startDrag(holder)
false
}
else -> {
false
}
}
}
}
private fun initList() {
list.clear()
val db = mHelper.readableDatabase
val cursor = db.query(
TaskContract.TaskEntry.TABLE,
arrayOf(
TaskContract.TaskEntry.ID,
TaskContract.TaskEntry.COL_TASK_TITLE,
TaskContract.TaskEntry.COL_TASK_TEXT,
TaskContract.TaskEntry.COL_TASK_DATE),null, null, null, null, TaskContract.TaskEntry.ID)
while (cursor.moveToNext()) {
val id = cursor.getColumnIndex(TaskContract.TaskEntry.ID)
val idTitle = cursor.getColumnIndex(TaskContract.TaskEntry.COL_TASK_TITLE)
val idText = cursor.getColumnIndex(TaskContract.TaskEntry.COL_TASK_TEXT)
val idDate = cursor.getColumnIndex(TaskContract.TaskEntry.COL_TASK_DATE)
list.add(MyObject(cursor.getString(id), cursor.getString(idTitle), cursor.getString(idText), cursor.getString(idDate)))
}
notifyDataSetChanged()
cursor.close()
db.close()
}
override fun getItemCount(): Int {
return list.size
}
override fun onViewMoved(oldPosition: Int, newPosition: Int) {
val target = list[oldPosition]
list.removeAt(oldPosition)
list.add(newPosition, target)
notifyItemMoved(oldPosition, newPosition)
}
override fun onViewSwiped(position: Int) {
deleteTask(list[position].ID)
list.removeAt(position)
notifyItemRemoved(position)
updateNotesPositionInDb()
}
fun setTouchHelper(touchHelper: ItemTouchHelper) {
this.touchHelper = touchHelper
}
fun addTask(taskTitle : String, taskText: String) {
val values = ContentValues()
val sdf = SimpleDateFormat("dd/MM/yyyy/", Locale.US)
val date = sdf.format(Date())
values.put(TaskContract.TaskEntry.ID, list.size)
values.put(TaskContract.TaskEntry.COL_TASK_TITLE, taskTitle)
values.put(TaskContract.TaskEntry.COL_TASK_TEXT, taskText)
values.put(TaskContract.TaskEntry.COL_TASK_DATE, date)
val db = mHelper.readableDatabase
db.insertWithOnConflict(TaskContract.TaskEntry.TABLE,
null,
values,
SQLiteDatabase.CONFLICT_REPLACE)
db.close()
list.add(MyObject(list.size.toString(), taskTitle, taskText, date))
notifyItemInserted(list.size)
}
fun addTask() {
val test: Activity = context as Activity
test.launchActivity<AddNoteActivity>(42) {
/* putExtra("user", "854")
p utExtra("user2", "46850") */
}
}
private fun deleteTask(taskId: String) {
val db = mHelper.readableDatabase
db.delete(TaskContract.TaskEntry.TABLE,
"id=$taskId", null)
db.close()
}
fun modifyTask(taskPosition: String, taskTitle: String, taskText: String) {
val target = list[taskPosition.toInt()]
target.title = taskTitle
target.text = taskText
val values = ContentValues()
val sdf = SimpleDateFormat("dd/MM/yyyy/", Locale.US)
val date = sdf.format(Date())
values.put(TaskContract.TaskEntry.ID, taskPosition)
values.put(TaskContract.TaskEntry.COL_TASK_TITLE, taskTitle)
values.put(TaskContract.TaskEntry.COL_TASK_TEXT, taskText)
values.put(TaskContract.TaskEntry.COL_TASK_DATE, date)
val db = mHelper.readableDatabase
db.update(TaskContract.TaskEntry.TABLE,
values, TaskContract.TaskEntry.ID + "=" + target.ID, null)
db.close()
notifyItemChanged(taskPosition.toInt())
}
private fun updateNotesPositionInDb() {
val db = mHelper.readableDatabase
var i = 0
while (i < list.size) {
val values = ContentValues()
values.put(TaskContract.TaskEntry.ID, i)
db.update(TaskContract.TaskEntry.TABLE,
values, TaskContract.TaskEntry.ID + "=? AND " + TaskContract.TaskEntry.COL_TASK_TITLE + "=?", arrayOf(list[i].ID, list[i].title))
i++
}
db.close()
}
I've tried reading Android Studio's official documentation, but it cannot solve my specific problem.

Answer 1

in your class MyViewHolder you have method called binding and you need also to implement it and add paramter
shoud be
class MyViewHolder(private val binding: CellCardsBinding): RecyclerView.ViewHolder(binding.root ) {
fun bind(data:MyObject) {
binding.yourView=data.title ...
}
}
in onBindViewHolder
..
holder.bind(myObject)

Answer 2

After switching from removing kotlin_extensions and switching to view binding, I received a "Unresolved reference: myViewHolder" in my onBindViewHolder method
Well, your onBindViewHolder method is passing a variable called holder and you're trying to use a variable called myViewHolder, so that seems like a problem.
// --------------------this-----v
override fun onBindViewHolder(holder: MyViewHolder, position: Int) {
val myObject = list[position]
// v--- doesn't match this
myViewHolder.bind(myObject)
and when I replace "myViewHolder" with "holder", it then gives me a "Unresolved reference: bind". How do I resolve this.
Your MyViewHolder class has a method called binding that takes no arguments. There is no bind method that takes a "myObject".
class MyViewHolder(val binding: CellCardsBinding): RecyclerView.ViewHolder(binding.root ) {
fun binding() {
}
}
Edit
You should pass an instance of the data class
class MyViewHolder(val binding: CellCardsBinding): RecyclerView.ViewHolder(binding.root ) {
fun bind(object: MyObject) {
// Set variables on binding
}
}
Then pass an instance from your list via onBindViewHolder:
override fun onBindViewHolder(holder: MyViewHolder, position: Int) {
val myObject = list[position]
holder.bind(myObject)
Please check this blog post for more.

Answer 3

I got my answer.
class MyAdapter(private val context: Context, private val mHelper : TaskDbHelper) : RecyclerView.Adapter<MyAdapter.MyViewHolder>(),
SwipeAndDragHelper.ActionCompletionContract {
class MyViewHolder(val binding: CellCardsBinding): RecyclerView.ViewHolder(binding.root ) {
private val titleView: TextView = itemView.findViewById<View>(R.id.title) as TextView
val textView: TextView = itemView.findViewById<View>(R.id.text) as TextView
private val dateTextView: TextView = itemView.findViewById<View>(R.id.date) as TextView
fun binding (myObject: MyObject) {
titleView.text = myObject.title
textView.text = myObject.text
dateTextView.text = myObject.date
}
}
I simply initialised the view I wanted to reference in my layout and called them in the binding() function.