FirestoreRecyclerAdapter jumps position when updating the first document

[BirdmanTunes]

• Android device: Google Pixel 2 XL
• Android OS version: 10
• Google Play Services version: 18.1.0
• Firebase/Play Services SDK version: 21.5.0
• FirebaseUI version: 6.3.0

Steps to reproduce:

• make a recyclerview connected to firestore that displays a list of shopping items showing item names only
• the shopping items change to crossed out when clicked on
• the shopping items are ordered by uncrossed first
• if your list contains about 20 elements go to the top and cross out the first item

Observed Results:

• the recyclerview will scroll down to the crossed out item
• does not happen when crossing any of the items except the first one

Expected Results:

• the crossed out item should just fly down and the list should not move

Relevant Code:

ShoppingAdapter.kt
https://hastebin.com/okezanasak.m

[samtstern]

@BirdmanTunes do you have any scroll listeners attached to your adapter or anything else that affects scrolling? There's nothing in FirebaseUI that controls scroll position so I would be surprised if this was a bug in the library.

[BirdmanTunes]

Nope, there is no code that attaches a scroll listener, it's just a basic recyclerview setup for firestore, this is how i attach my adapter, it's just default stuff except i have a decoration on it

val layoutManagerNote = LinearLayoutManager(this)
recyclerview_bottom_group.setHasFixedSize(false)
recyclerview_bottom_group.layoutManager = layoutManagerNote

val itemDecoration = DividerItemDecoration(
            recyclerview_bottom_group.context,
            layoutManagerNote.orientation
        )

itemDecoration.setDrawable(
            ContextCompat.getDrawable(
                this,
                R.drawable.divider_gray
            )!!
        )
recyclerview_bottom_group.addItemDecoration(
            itemDecoration
        )

val queryForShoppingItems = firebaseFirestore.collection("listOfNotes/" + documentReference?.id + "/shoppingItems").orderBy("checked", Query.Direction.ASCENDING)

val optionsForShoppingItems: FirestoreRecyclerOptions<ShoppingItem> =
                FirestoreRecyclerOptions.Builder<ShoppingItem>()
                    .setQuery(queryForShoppingItems, ShoppingItem::class.java)
                    .build()

shoppingAdapterGroup = ShoppingAdapterGroup(optionsForShoppingItems, this)

recyclerview_bottom_group.adapter = shoppingAdapterGroup

shoppingAdapterGroup?.startListening()

[BirdmanTunes]

I forgot to show, this is how i update the item

               shoppingAdapterGroup?.setClickListener(object: ShoppingAdapterGroup.OnItemClickListener {
                override fun onItemClick(documentSnapshot: DocumentSnapshot?, position: Int) {
                    val shoppingItem = documentSnapshot?.toObject(ShoppingItem::class.java)
                    val updatedFields = HashMap<String, Any>()
                    updatedFields["checked"] = !shoppingItem?.checked!!
                }
            })