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| import android.content.Context | |
| import android.view.LayoutInflater | |
| import android.view.View | |
| import android.view.ViewGroup | |
| import androidx.databinding.DataBindingUtil | |
| import androidx.databinding.ViewDataBinding | |
| import androidx.lifecycle.LifecycleOwner | |
| import androidx.recyclerview.widget.DiffUtil | |
| import androidx.recyclerview.widget.RecyclerView | |
| import androidx.viewbinding.ViewBinding | |
| private typealias InflateMethod = (inflater: LayoutInflater, parent: ViewGroup, attach: Boolean)->ViewBinding | |
| /** | |
| * A RecyclerView Adapter that makes use of ViewBinding and DataBinding views that are a part of RecyclerViews. | |
| * This removes the need of having to define a bunch of ViewHolders or repeated Adapter classes, by delegating | |
| * the work to the ViewBindingViewItem where you can define your view types, associate the view | |
| * [ViewBindingViewItem.createView] and bind the data [ViewBindingViewItem.data] to the view in [ViewBindingViewItem.bind] */ | |
| open class ViewBindingAdapter<Item: ViewBindingViewItem>( | |
| itemlist: List<Item>, | |
| val lifecycleOwner: LifecycleOwner? = null | |
| ):RecyclerView.Adapter<VBHolder2>() | |
| { | |
| private var list: List<Item> = itemlist | |
| private set | |
| /** | |
| * A map of view (xml id) vs whether or not the ViewBindingViewItem is a Databinding vs a ViewBinding. True means it is ViewBinding | |
| */ | |
| private val typeMap = mutableMapOf<Int, Any>() | |
| override fun getItemViewType(position: Int) = list[position].let { | |
| typeMap[it.viewType] = it.inflateMethod | |
| ?: it.bindingVar ?: throw RuntimeException("InflateMethod or BindingVar must be set") | |
| it.viewType | |
| } | |
| override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): VBHolder2 { | |
| return typeMap[viewType]?.let { | |
| val binding: ViewBinding = when (it){ | |
| is Int -> { | |
| DataBindingUtil.inflate(parent.inflater(), viewType, parent, false) | |
| } | |
| else -> { | |
| (it as InflateMethod).invoke(parent.inflater(), parent, false) | |
| } | |
| } | |
| lifecycleOwner?.let { | |
| if (binding is ViewDataBinding) | |
| binding.lifecycleOwner = it | |
| } | |
| VBHolder2(binding) | |
| } ?: throw RuntimeException("Please set a type") | |
| } | |
| override fun onBindViewHolder(holder: VBHolder2, position: Int) { | |
| list[position].internalBind(holder.binding, position) | |
| } | |
| override fun getItemCount(): Int = list.size | |
| fun submitNewList(newList: List<Item>, diffCallback: ViewBindingDiffUtil<Item> = ViewBindingDiffUtil(newList, list)) { | |
| val diffResult = DiffUtil.calculateDiff(diffCallback) | |
| diffResult.dispatchUpdatesTo(this) | |
| list = newList | |
| } | |
| } | |
| /** | |
| * Outside of setting the adapter for the recycler this is the only class that you will need to extend | |
| * or really fully interact with | |
| * [viewType] The view type for this UI Model, in most case this can be the layout id (R.layout.somelayout), other than that it can be ignored | |
| * for cases of homogeneous recyclerviews | |
| * [bindingVar] [Int] The binding var at least one being used in the xml if this is Databinding | |
| * [inflateMethod] The inflate method for the ViewBinding or Databinding class. Example SomeViewBinding::inflate | |
| */ | |
| abstract class ViewBindingViewItem( | |
| val viewType: Int = 0, | |
| val bindingVar: Int? = null, | |
| val inflateMethod: ((inflater: LayoutInflater, parent: ViewGroup, attach: Boolean)->ViewBinding)? = null | |
| ) | |
| { | |
| /** This is set right before the [bind] call **/ | |
| lateinit var context: Context | |
| fun internalBind(binding: ViewBinding, position: Int) { | |
| context = binding.root.context | |
| if (binding is ViewDataBinding) { | |
| bindingVar?.let { binding.setVariable(it, this) } | |
| } | |
| bind(binding, position) | |
| } | |
| /** | |
| * This method is responsible for binding the data onClick listeners, setting TextViews etc | |
| * [binding] the ViewBinding or DataBinding that was inflated/binded | |
| * [position] the position this item was pulled from the list, in case we alternate background colors | |
| * or something like that. | |
| */ | |
| open fun bind(binding: ViewBinding, position: Int){} | |
| } | |
| /** | |
| * The holder used internally | |
| */ | |
| class VBHolder2(val binding:ViewBinding): | |
| RecyclerView.ViewHolder(binding.root) | |
| open class ViewBindingDiffUtil<T>(val newList: List<T>, val oldList: List<T>): DiffUtil.Callback() { | |
| override fun getNewListSize(): Int { | |
| return newList.size | |
| } | |
| override fun getOldListSize() = oldList.size | |
| override fun areItemsTheSame( | |
| oldItemPosition: Int, | |
| newItemPosition: Int | |
| ): Boolean = false | |
| override fun areContentsTheSame( | |
| oldItemPosition: Int, | |
| newItemPosition: Int | |
| ): Boolean = false | |
| } | |
| /** | |
| * Convenience method to get the LayoutInflater | |
| */ | |
| private fun View.inflater() = LayoutInflater.from(context) |
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