I want to get isChecked data from checkbox from recycler view in this I am using Binding Adapter but I am not getting how to do that. If anyone has a way to do that then please share it.
class ItemListAdapter(private val itemDeleteListener: ItemDeleteListener,
private val checkItemListener: CheckItemListener) :
ListAdapter<ListItemTable, ItemListAdapter.ViewHolder>(ListItemDiffCallBack()) {
class ViewHolder(private val binding: ShowItemBinding) : RecyclerView.ViewHolder(binding.root) {
fun bind(listItemTable: ListItemTable, itemDeleteListener: ItemDeleteListener,
checkItemListener: CheckItemListener) {
binding.itemHistory = listItemTable
binding.itemDelete = itemDeleteListener
binding.checkItem = checkItemListener
binding.executePendingBindings()
}
companion object {
fun from(parent: ViewGroup): ViewHolder {
val layoutInflater = LayoutInflater.from(parent.context)
val binding = ShowItemBinding.inflate(layoutInflater, parent, false)
return ViewHolder(binding)
}
}
}
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): ViewHolder {
return ViewHolder.from(parent)
}
override fun onBindViewHolder(holder: ViewHolder, position: Int) {
holder.bind(getItem(position), itemDeleteListener, checkItemListener)
getItem(position).itemCompleted
}
class ItemDeleteListener(val clickListener: (listId: Long) -> Unit) {
fun onClick(listItemTable: ListItemTable) = clickListener(listItemTable.itemId)
}
class CheckItemListener(val clickListener: (listId: Long) -> Unit){
fun onClick(listItemTable: ListItemTable) = clickListener(listItemTable.itemId)
}
class ListItemDiffCallBack : DiffUtil.ItemCallback<ListItemTable>() {
override fun areItemsTheSame(oldItem: ListItemTable, newItem: ListItemTable): Boolean {
return oldItem.itemId == newItem.itemId
}
override fun areContentsTheSame(oldItem: ListItemTable, newItem: ListItemTable): Boolean {
return oldItem == newItem
}
}
}
See: https://developer.android.com/topic/libraries/data-binding/two-way
If you're using data binding I think you should take a look at two-way data binding. It's even introduced through this checkbox problem inside the docs, so you're in luck!
Edit: To be a bit more specific you would implement this like so:
Create a binding adapter that sets the property on the view
<layout>
<data>
<variable
name="itemHistory"
type="your.package.ListItemTable" />
<variable
name="checkItem"
type="android.widget.CompoundButton.OnCheckedChangeListener" />
<!-...->
</data>
<CheckBox
android:id="#+id/rememberMeCheckBox"
android:checked="#{itemHistory.itemCompleted}"
android:onCheckedChanged="#{checkItem}"
/>
</layout>
So you have to use OnCheckedChangeListener instead of your own listener, and pass that to your xml.
You already have 2 "listeners" on your constructor of the adapter and you are passing them to the view holder by using the bind method.
class ItemListAdapter(private val itemDeleteListener: ItemDeleteListener, private val checkItemListener: CheckItemListener)
So you have to pass the correct one to your view holder and then set the checkbox listener. Is better to use the constructor of the view holder to avoid passing the same listener on every binding
class ViewHolder(private val binding: ShowItemBinding, private val itemDeleteListener: ItemDeleteListener, private val checkItemListener: CheckItemListener) {
fun bind(listItemTable: ListItemTable) {
binding.YOUR_CHECKBOX.setOnCheckedChangeListener(null)
binding.itemHistory = listItemTable
binding.itemDelete = itemDeleteListener
binding.checkItem = checkItemListener
binding.executePendingBindings()
binding.YOUR_CHECKBOX.setOnCheckedChangeListener { -, isChecked ->
//here call your "listener" by example
checkItemListener.theMethod(isChecked)
}
}
}
We set the checkbox listener to null first so we can stop listening and then set the view values, otherwise, anything changing the view will also trigger the listener, once the view values are set, then set the checkbox listener to trigger the callbacks.
Related
I know that there are similar questions to this, but I just cant find something that is similar, I've been studying new things to learn, and while converting kotlin synthetics to viewvbinding mode, I've encountered this error
kotlin.UninitializedPropertyAccessException: lateinit property binding has not been initialized
at com.codepalace.chatbot.ui.MessagingAdapter.onBindViewHolder(MessagingAdapter.kt:60)
at com.codepalace.chatbot.ui.MessagingAdapter.onBindViewHolder(MessagingAdapter.kt:17)
It says that I have to initialize the binding, but I dont know where to put it.
This is the code.
class MessagingAdapter: RecyclerView.Adapter<MessagingAdapter.MessageViewHolder>() {
var messagesList = mutableListOf<Message>()
private lateinit var binding: MessageItemBinding
inner class MessageViewHolder(itemView: View) : RecyclerView.ViewHolder(itemView) {
init {
itemView.setOnClickListener {
//Remove message on the item clicked
messagesList.removeAt(adapterPosition)
notifyItemRemoved(adapterPosition)
}
}
}
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): MessageViewHolder {
return MessageViewHolder(
LayoutInflater.from(parent.context).inflate(R.layout.message_item, parent, false)
)
}
override fun getItemCount(): Int {
return messagesList.size
}
#SuppressLint("SetTextI18n")
override fun onBindViewHolder(holder: MessageViewHolder, position: Int) {
val currentMessage = messagesList[position]
when (currentMessage.id) {
SEND_ID -> {
holder.itemView.findViewById<View>(R.id.tv_message).apply {
binding.tvMessage.text = currentMessage.message
visibility = View.VISIBLE
}
holder.itemView.findViewById<View>(R.id.tv_bot_message).visibility = View.GONE
}
RECEIVE_ID -> {
holder.itemView.findViewById<View>(R.id.tv_bot_message).apply {
binding.tvBotMessage.text = currentMessage.message
visibility = View.VISIBLE
}
holder.itemView.findViewById<View>(R.id.tv_message).visibility = View.GONE
}
}
}
fun insertMessage(message: Message) {
this.messagesList.add(message)
notifyItemInserted(messagesList.size)
}
private lateinit var binding: MessageItemBinding
You didn't initialize the binding object, as you defined it as lateinit, then you should define it.
This is typically in onCreateViewHolder
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): TrackedActivityHolder {
val inflater = LayoutInflater.from(parent.context)
binding = DataBindingUtil.inflate<MessageItemBinding>(inflater, R.layout.message_item, parent, false)
return MessageViewHolder(
binding
)
}
UPDATE
You need to accept MessageItemBinding type instead of View in the MessageViewHolder constructor, and use itemView.root to get the root view of the list item.
inner class MessageViewHolder(itemView: MessageItemBinding) : RecyclerView.ViewHolder(itemView.root) {
init {
itemView.root.setOnClickListener {
//Remove message on the item clicked
messagesList.removeAt(adapterPosition)
notifyItemRemoved(adapterPosition)
}
}
}
The reason why You get this error is that MessageItemBinding should not be in Adapter but in ViewHolder class. You can make RecyclerView like this:
object MessageDiffCallback : DiffUtil.ItemCallback<Message>()
{
override fun areItemsTheSame(
oldItem: Message,
newItem: Message
): Boolean =
oldItem.id == newItem.id
override fun areContentsTheSame(
oldItem: Message,
newItem: Message
): Boolean =
oldItem == newItem
}
I assume that Message is a data class. You have to create this MessageDiffCallback and override these 2 methods in a similar way that I did it.
Now Create ViewHolder class:
class MessageViewHolder private constructor(
private val binding: MessageItemBinding
) : RecyclerView.ViewHolder(binding.root)
{
companion object
{
fun create(parent: ViewGroup): MessageViewHolder
{
val layoutInflater = LayoutInflater.from(parent.context)
val binding = MessageItemBinding.inflate(layoutInflater, parent, false)
return MessageViewHolder(
binding
)
}
}
fun bind(
message: Messaage
)
{
// Here You can do everything.
// You pass the message and based on this You can set up a view and use binding
}
}
And now Adapter class
class MessageAdapter : ListAdapter<Message, MessageViewHolder>(MessageDiffCallback)
{
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): MessageViewHolder =
MessageViewHolder.create(parent)
override fun onBindViewHolder(holder: MessageViewHolder, position: Int) =
holder.bind(
message = getItem(position),
)
}
Now You should have a working adapter. To put data in it use messageAdapter.submitList(messages) in Your Fragment/Activity
Maybe not the best answer because it changes Your code and uses a little different logic but it should work better. You can check google sample code here or take codelab here. It is free after signing up
Here it's my adapter code ;
class ModelViewHolder(view: View) : RecyclerView.ViewHolder(view) {
private val chName: TextView = view.findViewById(R.id.chName)
private val chBirthYear: TextView = view.findViewById(R.id.chBirthYear)
private val chHeight: TextView = view.findViewById(R.id.chHeight)
private val chHomeWorld: TextView = view.findViewById(R.id.chHomeWorld)
Get the list item view binding class and change it like this:
//ItemModelBinding is the generated binding class for the list view item
class ModelViewHolder(val binding: ItemModelBinding) : RecyclerView.ViewHolder(binding.root) {
fun bind(item: SomeModelClass) {
binding.chName = item.chName
binding.chBirthYear = item.chBirthYear
binding.chHeight = item.chHeight
binding.chHomeWorld= item.chHomeWorld
binding.executePendingBindings()
}
override fun onBindViewHolder(holder: ModelViewHolder, position: Int) {
val item = getItem(position)
holder.bind(item)
}
class ModelViewHolder(view: View) RecyclerView.ViewHolder(view){
val binding = LayoutYouWantToUseBinding.bind(view)
}
ListAdapter is RecyclerView.Adapter base class for presenting List data in a RecyclerView, including computing diffs between Lists on a background thread.
DiffUtil helps in computing the difference between two lists on a background thread. and only update the view for which data has been changed means less number of call of onBindViewHolder() which would have called for all the item if we still stick with notifyDataSetChanged() on any data change.
class ModelAdapter : ListAdapter<Model, ModelAdapter.ModelViewHolder>(ModelDiffCallBack()) {
class ModelViewHolder(private val binding: ModelItemLayoutBinding) :
RecyclerView.ViewHolder(binding.root) {
fun bind(model: Model) {
//if data binding is also enabled
binding.model = model
//else set data for each view one after another
binding.txtTitle.text = model.title
//and so on for all the items
binding.executePendingBindings()
}
companion object {
fun from(parent: ViewGroup): ModelViewHolder {
val layoutInflater = LayoutInflater.from(parent.context)
val binding = ModelItemLayoutBinding.inflate(layoutInflater, parent, false)
return ModelViewHolder(binding)
}
}
}
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): ModelViewHolder =
ModelViewHolder.from(parent)
override fun onBindViewHolder(holder: ModelViewHolder, position: Int) {
val model = getItem(position)
holder.bind(model)
}
class ModelDiffCallBack : DiffUtil.ItemCallback<Model>() {
override fun areItemsTheSame(oldItem: Model, newItem: Model): Boolean =
oldItem === newItem
override fun areContentsTheSame(oldItem: Model, newItem: Model): Boolean =
oldItem == newItem
}
}
In my app, there is an Activity which has a RecyclerView inside, which loads the list of options needed for that screen.
In the code below, i tried to implement a binder, which is needed because of the recent Android changes.
However, when i open the activity starts, the application crashes, throwing this error, linking the line with binding = ItemSettingsBinding.bind(binding.root):
kotlin.UninitializedPropertyAccessException: lateinit property binding has not been initialized
What am i doing wrong? What's the correct way to implement a binder inside an adapter?
AdapterSettings.kt
class AdapterSettings(
var settingsList: List<DataItemSettings>,
var listener: OnItemClickListener
) : RecyclerView.Adapter<AdapterSettings.SettingsViewHolder>() {
private lateinit var binding: ItemSettingsBinding
inner class SettingsViewHolder(itemView: View) : RecyclerView.ViewHolder(itemView), View.OnClickListener {
init {
itemView.setOnClickListener(this)
}
override fun onClick(p0: View?) {
val position : Int = adapterPosition
if (position != RecyclerView.NO_POSITION) {
listener.OnItemClick(position)
}
}
}
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): SettingsViewHolder {
val view = LayoutInflater.from(parent.context).inflate(R.layout.item_settings, parent, false)
return SettingsViewHolder(view)
}
override fun getItemCount(): Int {
return settingsList.size
}
override fun onBindViewHolder(holder: SettingsViewHolder, position: Int) {
binding = ItemSettingsBinding.bind(binding.root)
holder.itemView.apply {
binding.rvTitle.text = settingsList[position].stringTitle
binding.rvDescription.text = settingsList[position].stringDescription
binding.rvIcon.setImageResource(settingsList[position].itemIcon)
}
}
interface OnItemClickListener {
fun OnItemClick(position: Int)
}
}
I believe you're missing your inflate in onCreateViewHolder:
// Pseudo-Code
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): SettingsViewHolder {
val binding = ItemSettingsBinding
.inflate(LayoutInflater.from(parent.context), parent, false)
return SettingsViewHolder(binding)
}
Then you can make use of it.
Create the binding in onCreateViewHolder and pass the binding into the ViewHolder instead of the inflated View. Thus you create a binding for each created view and only need to do the apply stuff in the onBindViewHolder
Example:
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): SettingsViewHolder {
val view = LayoutInflater.from(parent.context).inflate(R.layout.item_settings, parent, false)
val binding = ItemSettingsBinding.bind(view)
return SettingsViewHolder(binding)
}
override fun onBindViewHolder(holder: SettingsViewHolder, position: Int) {
holder.binding.apply {
rvTitle.text = settingsList[position].stringTitle
rvDescription.text = settingsList[position].stringDescription
rvIcon.setImageResource(settingsList[position].itemIcon)
}
}
Adapt your ViewHolder accordingly
There is indeed another way to ViewBind in an adapter.
First, we need to setup the ViewHolder in a different way:
inner class SettingsViewHolder(private val binding: ItemSettingsBinding):
RecyclerView.ViewHolder(binding.root), View.OnClickListener {
With this, we created a binding value inside the brackets, so we are able to call the items of the actual view or layout trough binding.root
Inside the viewholder, we need to create a function used to bind our items. We can either bind like this:
fun bind(item: Item) {
binding.item = item
binding.executePendingBindings()
}
Or like this:
fun bind(item: DataItemSettings) {
binding.rvTitle.text = settingsList[position].stringTitle
binding.rvDescription.text = settingsList[position].stringDescription
binding.rvIcon.setImageResource(settingsList[position].itemIcon)
}
NOTICE: 'getter for position: Int' is deprecated. Deprecated in Java.
And, final step, we need to write this, inside bindViewHolder:
override fun onBindViewHolder(holder: SettingsViewHolder, position: Int) {
holder.bind(settingsList[position])
}
Imagine we have a simple list of items. Each item contains only a short title.
To handle the list we are using RecyclerView with ListAdapter and ViewHolders.
Each item/view is not editable unless we click it.
In this scenario I am using one view model for list and one for item under edit.
Unfortunately all my attempts failed.
I have tried to use two different view holders but the list was flickering, after all inflating view (in this case binding) is heavy.
Another shot I was giving to use the same view holder but with two various bind methods - one binding plain item, second binding with viewmodel instead of data object but it failed as well - suddenly a few rows were editable.
Has anyone solved it ?
class MistakesAdapter(private val editViewModel: MistakeEditViewModel) :
ListAdapter<Mistake, RecyclerView.ViewHolder>(MistakesDiffCallback()) {
companion object{
const val ITEM_PLAIN_VIEW_TYPE = 0
const val ITEM_EDITABLE_VIEW_TYPE = 1
}
private var itemPositionUnderEdit = -1
private val listener = object: MistakeItemListener{
override fun onClick(view: View, position: Int) {
Timber.d("OnClick : edit - $itemPositionUnderEdit, clickPos - $position")
editViewModel.onEditMistake(getItem(position))
itemPositionUnderEdit = position
notifyItemChanged(itemPositionUnderEdit)
}
}
override fun getItemViewType(position: Int) =
when (position) {
itemPositionUnderEdit -> ITEM_EDITABLE_VIEW_TYPE
else -> ITEM_PLAIN_VIEW_TYPE
}
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int) =
when (viewType) {
ITEM_EDITABLE_VIEW_TYPE -> EditableMistakeViewHolder.from(parent)
else -> MistakeViewHolder.from(parent)
}
override fun onBindViewHolder(holder: RecyclerView.ViewHolder, position: Int) {
when (holder) {
is EditableMistakeViewHolder -> holder.bind(editViewModel, listener)
is MistakeViewHolder -> holder.bind(getItem(position), listener)
else -> throw ClassCastException("Unknown view holder type")
}
}
class MistakeViewHolder private constructor(private val binding: ListItemMistakesBinding) :
RecyclerView.ViewHolder(binding.root) {
companion object {
fun from(viewGroup: ViewGroup): MistakeViewHolder {
val inflater = LayoutInflater.from(viewGroup.context)
val binding = ListItemMistakesBinding.inflate(inflater, viewGroup, false)
return MistakeViewHolder(binding)
}
}
fun bind(item: Mistake, listener: MistakeItemListener) {
binding.apply {
mistake = item
inputType = InputType.TYPE_NULL
this.listener = listener
position = adapterPosition
executePendingBindings()
}
}
}
class EditableMistakeViewHolder private constructor(private val binding: ListItemMistakesBinding)
: RecyclerView.ViewHolder(binding.root) {
companion object{
fun from(viewGroup: ViewGroup): EditableMistakeViewHolder {
val inflater = LayoutInflater.from(viewGroup.context)
val binding = ListItemMistakesBinding.inflate(inflater, viewGroup, false)
return EditableMistakeViewHolder(binding)
}
}
fun bind(viewModel: MistakeEditViewModel, listener: MistakeItemListener){
binding.apply {
this.viewModel = viewModel
inputType = InputType.TYPE_CLASS_TEXT
this.listener = listener
position = adapterPosition
root.setBackgroundColor(Color.GRAY)
}
}
}
}
class MistakeEditViewModel(private val repository: MistakesRepository) : ViewModel() {
#VisibleForTesting
var mistakeUnderEdit: Mistake? = null
//two-way binding
val mistakeName = MutableLiveData<String>()
fun onEditMistake(mistake: Mistake) {
mistakeUnderEdit = mistake
mistakeName.value = mistake.name
}
}
By changing my approach to the problem I solved it.
I make all list items editable but at the same time I am following focus.
To cut the long story short, I invoke item view model methods with help of OnFocusChangeListener and TextWatcher on my editTexts.
I am fetching a list of categories from an api and setting them into recyclerview . Adapter code is written in viewModel class and is called by the fragment that is calling the api. Below are the methods for setting adapters.
fun getAdapter(
listener: OtherVideoCategoriesRecyclerAdapter.OtherVideoCategoriesRecyclerAdapterListener,context: Context
): OtherVideoCategoriesRecyclerAdapter {
if (categoriesRecyclerAdapter == null)
categoriesRecyclerAdapter = OtherVideoCategoriesRecyclerAdapter(listener,context)
return categoriesRecyclerAdapter as OtherVideoCategoriesRecyclerAdapter
}
fun setItems(categories: ArrayList<OtherCategoriesItem>) {
categoriesList = categories
categoriesRecyclerAdapter!!.setItems(categoriesList!!)
}
And this is how I call these methods from my fragment class.
otherVideoViewModel.setItems(it.first.data!!.otherCategories as ArrayList<OtherCategoriesItem>)
Set Adapter method
private fun setAdapter() {
otherVideosCategoriesBinding.recyclerView.layoutManager = LinearLayoutManager(activity)
otherVideosCategoriesBinding.recyclerView.itemAnimator = DefaultItemAnimator()
adapter = otherVideoViewModel.getAdapter(adapterListener,activity!!)
otherVideosCategoriesBinding.recyclerView.adapter = adapter
}
And this is the adapter class.
class OtherVideoCategoriesRecyclerAdapter(private val listener: OtherVideoCategoriesRecyclerAdapterListener,val context: Context): RecyclerView.Adapter<OtherVideoCategoriesRecyclerAdapter.ViewHolder>() {
var categories = ArrayList<OtherCategoriesItem>()
interface OtherVideoCategoriesRecyclerAdapterListener {
fun onItemClicked(position: Int)
}
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): OtherVideoCategoriesRecyclerAdapter.ViewHolder {
val inflater=LayoutInflater.from(context)
val binding = ItemOtherVideoCategoryBinding.inflate(inflater, parent, false)
return OtherVideoCategoriesRecyclerAdapter.ViewHolder(binding)
}
override fun getItemCount(): Int {
return categories.size
}
override fun onBindViewHolder(holder: OtherVideoCategoriesRecyclerAdapter.ViewHolder, position: Int) {
val item = categories[position]
holder.bindViews(item)
}
class ViewHolder(private val binding: ItemOtherVideoCategoryBinding): RecyclerView.ViewHolder(binding.root) {
fun bindViews(model: OtherCategoriesItem){
binding.model=model
binding.executePendingBindings()
}
}
fun setItems(categoriesList: ArrayList<OtherCategoriesItem>) {
categories = categoriesList
notifyDataSetChanged()
}
}
When I run this code, it crashes with following exception.
java.lang.IllegalStateException: ViewHolder views must not be attached when created. Ensure that you are not passing 'true' to the attachToRoot parameter of LayoutInflater.inflate(..., boolean attachToRoot)
I have tried all the related answers to this error but none of them worked for my case as many of those answers doesn't included data binding.
Hey just changing your onCreateViewHolder a bit. Try this:
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): OtherVideoCategoriesRecyclerAdapter.ViewHolder {
val inflater=LayoutInflater.from(context)
val binding:ItemOtherVideoCategoryBinding = DataBindingUtil.inflate(inflater,R.layout.your_layout_name, parent, false)
return OtherVideoCategoriesRecyclerAdapter.ViewHolder(binding)
}