JarCastingTypedRecyclerView
A lot of Android Apps today have complicated lists with multiple different views. The way to go today is to use a RecyclerView but the setup of a RecyclerView with a Adapter with multiple view types is tedious and error-prone.
I present to you TypedRecyclerView. A very small library to simplify the creation of multi-type RecyclerViews.
Setup
For every item type in your RecyclerView create a class that will represent the state of that item. This class has to implement the TypedRecyclerViewItem interface.
data class Item(
val id: Long = 0L,
val text: String = ""
) : TypedRecyclerViewItem {
override fun getItemType(): Int {
return 0
}
override fun isTheSameAs(other: TypedRecyclerViewItem): Boolean {
return if (other is Item) {
this.id == other.id
} else {
false
}
}
override fun contentsAreTheSameAs(other: TypedRecyclerViewItem): Boolean {
return if (other is Item) {
this == other
} else {
false
}
}
}
Afterwards you just have to use TypedRecyclerViewAdapter as your RecyclerView Adapter.
Create a TypedViewHolder so that the RecyclerView knows how to handle your views:
class TypeOne : TypedViewHolder {
override fun onCreateViewHolder(parent: ViewGroup): RecyclerView.ViewHolder {
val viewOne = YourView(parent.context)
viewOne.layoutParams = ViewGroup.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.WRAP_CONTENT)
viewOne.id = ViewCompat.generateViewId()
return ViewHolder(viewOne)
}
override fun onBindViewHolder(
typedItem: TypedRecyclerViewItem?,
holder: RecyclerView.ViewHolder
) {
(holder as? ViewHolder)?.let { currentViewHolder ->
(typedItem as? Item)?.let { currentItem ->
currentViewHolder.view.text = currentItem.text
}
}
}
class ViewHolder(val view: YourView) : RecyclerView.ViewHolder(view)
}
Finally you have to register the different types of views:
adapter.registerViewHolderType(0, TypeOne())
Thats it, you can now use your RecyclerView as you are used to and use the function dispatchItems(items) on your adpter to update its data.
A full example can be found inside the repository under /sample.