Prompt Title: Kotlin RV Adapter: 2 ViewTypes

Sure, I can help you create a RecyclerView.Adapter with two different view types using DiffUtil in Kotlin. Let's first define our data model:

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data class ListItem(
    val id: String,
    val type: Int,
    val title: String,
    val description: String? = null
)

In this model, type determines the type of view, and description might be null for one of the types. We have a unique id which will help DiffUtil to understand which items have been changed.

Now, let's create our DiffUtil.ItemCallback:

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val DIFF_CALLBACK = object : DiffUtil.ItemCallback<ListItem>() {
    override fun areItemsTheSame(oldItem: ListItem, newItem: ListItem): Boolean {
        return oldItem.id == newItem.id
    }

    override fun areContentsTheSame(oldItem: ListItem, newItem: ListItem): Boolean {
        return oldItem == newItem
    }

    override fun getChangePayload(oldItem: ListItem, newItem: ListItem): Any? {
        val diffBundle = Bundle()
        if (oldItem.title != newItem.title) {
            diffBundle.putString("title", newItem.title)
        }
        if (oldItem.description != newItem.description) {
            diffBundle.putString("description", newItem.description)
        }
        return if (diffBundle.size() != 0) diffBundle else super.getChangePayload(oldItem, newItem)
    }
}

Finally, let's create the RecyclerView.Adapter:

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class MyAdapter : ListAdapter<ListItem, RecyclerView.ViewHolder>(DIFF_CALLBACK) {

    override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): RecyclerView.ViewHolder {
        val inflater = LayoutInflater.from(parent.context)
        return when (viewType) {
            0 -> ViewHolderType0(inflater.inflate(R.layout.item_type_0, parent, false))
            1 -> ViewHolderType1(inflater.inflate(R.layout.item_type_1, parent, false))
            else -> throw IllegalArgumentException("Invalid view type")
        }
    }

    override fun onBindViewHolder(holder: RecyclerView.ViewHolder, position: Int) {
        when (holder) {
            is ViewHolderType0 -> holder.bind(getItem(position))
            is ViewHolderType1 -> holder.bind(getItem(position))
        }
    }

    override fun onBindViewHolder(holder: RecyclerView.ViewHolder, position: Int, payloads: MutableList<Any>) {
        if (payloads.isEmpty()) {
            super.onBindViewHolder(holder, position, payloads)
        } else {
            val combinedChange = createCombinedPayload(payloads as List<Bundle>)
            when (holder) {
                is ViewHolderType0 -> holder.updatePayload(getItem(position), combinedChange)
                is ViewHolderType1 -> holder.updatePayload(getItem(position), combinedChange)
            }
        }
    }

    override fun getItemViewType(position: Int): Int {
        return getItem(position).type
    }

    private fun createCombinedPayload(payloads: List<Bundle>): Bundle {
        val fullUpdate = Bundle()
        for (change in payloads) {
            fullUpdate.putAll(change)
        }
        return fullUpdate
    }

    inner class ViewHolderType0(itemView: View) : RecyclerView.ViewHolder(itemView) {
        fun bind(item: ListItem) {
            // Bind the data
        }

        fun updatePayload(item: ListItem, change: Bundle) {
            // Update view with payload
        }
    }

    inner class ViewHolderType1(itemView: View) : RecyclerView.ViewHolder(itemView) {
        fun bind(item: ListItem) {
            // Bind the data
        }

        fun updatePayload(item: ListItem, change: Bundle) {
            // Update view with payload
        }
    }
}

In the above adapter:

• We create two types of ViewHolders for different view types.
• In the onBindViewHolder(holder: RecyclerView.ViewHolder, position: Int) method, we bind the data to the holder without any payloads.
• In the onBindViewHolder(holder: RecyclerView.ViewHolder, position: Int, payloads: MutableList<Any>) method, we handle the payloads.
• createCombinedPayload(payloads: List<Bundle>): Bundle method helps to combine all the payloads together.

Please note that R.layout.item_type_0 and R.layout.item_type_1 are the XML layout files for each of the two view types. You need to create those layout files according to your design. Also, you need to implement bind(item: ListItem) and updatePayload(item: ListItem, change: Bundle) methods in each ViewHolder according to your needs.