Swipe to dismiss in Android Kotlin - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to create a simple swipe-to-dismiss behavior using ItemTouchHelper.

Android Kotlin

val itemTouchHelper = ItemTouchHelper(object : ItemTouchHelper.SimpleCallback(0, [1]) {
    override fun onMove(recyclerView: RecyclerView, viewHolder: RecyclerView.ViewHolder, target: RecyclerView.ViewHolder): Boolean {
        return false
    }

    override fun onSwiped(viewHolder: RecyclerView.ViewHolder, direction: Int) {
        // Handle item dismissal here
    }
})

Drag options to blanks, or click blank then click option'

AItemTouchHelper.DOWN

BItemTouchHelper.LEFT

CItemTouchHelper.RIGHT

DItemTouchHelper.UP

Attempts:

3 left

💡 Hint

Common Mistakes

Using UP or DOWN instead of LEFT or RIGHT for swipe direction.

Confusing swipe directions with move directions.

The swipe direction for dismissing an item to the left is ItemTouchHelper.LEFT.

2fill in blank

medium

Complete the code to attach the ItemTouchHelper to the RecyclerView.

Android Kotlin

itemTouchHelper.[1](recyclerView)

Drag options to blanks, or click blank then click option'

AconnectRecyclerView

BbindRecyclerView

CattachToRecyclerView

DsetRecyclerView

Attempts:

3 left

💡 Hint

Common Mistakes

Using non-existent methods like bindRecyclerView or setRecyclerView.

Forgetting to attach the helper to the RecyclerView.

The correct method to attach ItemTouchHelper to RecyclerView is attachToRecyclerView().

3fill in blank

hard

Fix the error in the onSwiped method to remove the dismissed item from the adapter's data list named 'items'.

Android Kotlin

override fun onSwiped(viewHolder: RecyclerView.ViewHolder, direction: Int) {
    val position = viewHolder.adapterPosition
    items.[1](position)
    adapter.notifyItemRemoved(position)
}

Drag options to blanks, or click blank then click option'

AremoveAt

Bdelete

Cremove

Ddiscard

Attempts:

3 left

💡 Hint

Common Mistakes

Using remove() which expects an object, not an index.

Using non-existent methods like delete or discard.

The correct Kotlin List method to remove an item by index is removeAt().

4fill in blank

hard

Fill both blanks to enable swipe to dismiss only in the right direction and disable drag.

Android Kotlin

val itemTouchHelper = ItemTouchHelper(object : ItemTouchHelper.SimpleCallback([1], [2]) {
    override fun onMove(recyclerView: RecyclerView, viewHolder: RecyclerView.ViewHolder, target: RecyclerView.ViewHolder): Boolean {
        return false
    }

    override fun onSwiped(viewHolder: RecyclerView.ViewHolder, direction: Int) {
        // Handle swipe
    }
})

Drag options to blanks, or click blank then click option'

A0

BItemTouchHelper.RIGHT

CItemTouchHelper.LEFT

DItemTouchHelper.UP

Attempts:

3 left

💡 Hint

Common Mistakes

Setting dragDirs to non-zero values enabling drag.

Using wrong swipe direction constants.

Drag directions are set to 0 to disable drag. Swipe direction is set to ItemTouchHelper.RIGHT to allow swipe right only.

5fill in blank

hard

Complete the code to create a swipe-to-dismiss that removes the item and shows a Toast with the dismissed item's name.

Android Kotlin

override fun onSwiped(viewHolder: RecyclerView.ViewHolder, direction: Int) {
    val position = viewHolder.adapterPosition
    val item = items[position]
    items.removeAt(position)
    adapter.notifyItemRemoved(position)
    Toast.makeText(context, "Dismissed: " + item[1], Toast.LENGTH_SHORT).show()
}

Drag options to blanks, or click blank then click option'

A[

BremoveAt

C.name

D]

Attempts:

3 left

💡 Hint

Common Mistakes

Using parentheses instead of brackets to access list item.

Forgetting to remove the item from the list.

Not accessing the item's name property correctly.

Use [position] to get the item, removeAt(position) to remove it, and .name to get the item's name for the Toast.