How to implement swipe to archive and delete functionality in a RecyclerView in Kotlin Android

How to implement swipe to archive and delete functionality in a RecyclerView in Kotlin Android.

Here's a step-by-step tutorial on how to implement swipe to archive and delete functionality in a RecyclerView in Kotlin Android:

Step 1: Set up your project

Create a new Android project in Kotlin and add the necessary dependencies in your app-level build.gradle file:

dependencies {
    implementation 'androidx.recyclerview:recyclerview:1.1.0'
    implementation 'androidx.recyclerview:recyclerview-selection:1.1.0'
}

Step 2: Design your RecyclerView item layout

Create a layout file for your RecyclerView item (e.g., item_view.xml). This layout will represent each individual item in the RecyclerView. Customize it according to your requirements. For example, you can include a TextView for displaying item text and ImageView for displaying an icon.

Step 3: Create a RecyclerViewAdapter

Create a new Kotlin class called RecyclerViewAdapter that extends RecyclerView.Adapter. This class will be responsible for managing the data and creating the RecyclerView item views.

class RecyclerViewAdapter(private val items: List<String>) : RecyclerView.Adapter<RecyclerViewAdapter.ViewHolder>() {

    override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): ViewHolder {
        val view = LayoutInflater.from(parent.context).inflate(R.layout.item_view, parent, false)
        return ViewHolder(view)
    }

    override fun onBindViewHolder(holder: ViewHolder, position: Int) {
        val item = items[position]
        holder.textView.text = item
    }

    override fun getItemCount(): Int {
        return items.size
    }

    inner class ViewHolder(itemView: View) : RecyclerView.ViewHolder(itemView) {
        val textView: TextView = itemView.findViewById(R.id.textView)
    }
}

Step 4: Implement swipe functionality

Add the following code to your RecyclerViewAdapter class to enable swipe-to-archive and swipe-to-delete functionality:

class RecyclerViewAdapter(private val items: MutableList<String>) : RecyclerView.Adapter<RecyclerViewAdapter.ViewHolder>(), ItemTouchHelperAdapter {

    override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): ViewHolder {
        // Same as before
    }

    override fun onBindViewHolder(holder: ViewHolder, position: Int) {
        // Same as before
    }

    override fun getItemCount(): Int {
        return items.size
    }

    inner class ViewHolder(itemView: View) : RecyclerView.ViewHolder(itemView) {
        // Same as before
    }

    override fun onItemSwiped(position: Int, direction: Int) {
        if (direction == ItemTouchHelper.LEFT) {
            archiveItem(position)
        } else if (direction == ItemTouchHelper.RIGHT) {
            deleteItem(position)
        }
    }

    private fun archiveItem(position: Int) {
        // Implement archive logic here
        // For example, remove the item from the list or update its status
        items.removeAt(position)
        notifyItemRemoved(position)
    }

    private fun deleteItem(position: Int) {
        // Implement delete logic here
        // For example, remove the item from the list permanently
        items.removeAt(position)
        notifyItemRemoved(position)
    }
}

Step 5: Implement ItemTouchHelper

Create a new Kotlin class called ItemTouchHelperCallback that extends ItemTouchHelper.Callback. This class will handle the swipe gestures and notify the RecyclerViewAdapter about the swiped item.

class ItemTouchHelperCallback(private val adapter: ItemTouchHelperAdapter) : ItemTouchHelper.Callback() {

    override fun isItemViewSwipeEnabled(): Boolean {
        return true
    }

    override fun getMovementFlags(recyclerView: RecyclerView, viewHolder: RecyclerView.ViewHolder): Int {
        val swipeFlags = ItemTouchHelper.START or ItemTouchHelper.END // Enable both left and right swipe
        return makeMovementFlags(0, swipeFlags)
    }

    override fun onMove(
        recyclerView: RecyclerView,
        viewHolder: RecyclerView.ViewHolder,
        target: RecyclerView.ViewHolder
    ): Boolean {
        return false
    }

    override fun onSwiped(viewHolder: RecyclerView.ViewHolder, direction: Int) {
        adapter.onItemSwiped(viewHolder.adapterPosition, direction)
    }
}

Step 6: Set up ItemTouchHelper

In your activity or fragment, create an instance of ItemTouchHelper and attach it to your RecyclerView. Also, make sure your activity or fragment implements ItemTouchHelperAdapter.

class MainActivity : AppCompatActivity(), ItemTouchHelperAdapter {

    private lateinit var recyclerView: RecyclerView

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)

        recyclerView = findViewById(R.id.recyclerView)
        recyclerView.layoutManager = LinearLayoutManager(this)
        val adapter = RecyclerViewAdapter(getItems())
        recyclerView.adapter = adapter

        val itemTouchHelperCallback = ItemTouchHelperCallback(adapter)
        val itemTouchHelper = ItemTouchHelper(itemTouchHelperCallback)
        itemTouchHelper.attachToRecyclerView(recyclerView)
    }

    // Implement this method if you want to pass data to the RecyclerViewAdapter
    private fun getItems(): MutableList<String> {
        // Return your list of items here
    }

    override fun onItemSwiped(position: Int, direction: Int) {
        // Implement this method if you want to perform any additional actions when an item is swiped
    }
}

That's it! You have successfully implemented swipe to archive and delete functionality in a RecyclerView using Kotlin in Android.