Problem With Implementing Pagination Data Load Before Reach At Last Card

I am trying to implement Pagination in My project but i don't how it loads all the data from Firestore. I tried my Own method to Paginate but i don't where i am wrong with paginati

Solution 1:

My example hope it help

  page = 0var previous = 0val viewth = 20
      recyclerView.addOnScrollListener(object : RecyclerView.OnScrollListener() {
                    overridefunonScrolled(recyclerView: RecyclerView, dx: Int, dy: Int) {
                        super.onScrolled(recyclerView, dx, dy)
                        visible = gridLayoutManager.childCount
                        total = gridLayoutManager.itemCount
                        past = gridLayoutManager.findFirstVisibleItemPosition()
                        if (dy > 0) {
                            if (loading) {
                                if (total > previous) {
                                    loading = false
                                    previous = total
                                }
                            }
                            if (!loading && (total - visible) <= (past + viewth)) {
                                page++
                                getNextData(page.toString(), range)//call your next set
                                loading = true
                            }
                        } else {
                            mSwipeRefreshLayout.isEnabled = gridLayoutManager.findFirstCompletelyVisibleItemPosition() == 0
                        }

                    }

                    overridefunonScrollStateChanged(recyclerView: RecyclerView, newState: Int) {
                        super.onScrollStateChanged(recyclerView, newState)
                        mSwipeRefreshLayout.isEnabled = gridLayoutManager.findFirstCompletelyVisibleItemPosition() == 0
                    }

                })

Solution 2:

try to edit Git More Book like this

privatefungetMoreBooks(lastBook: Timestamp) {
    bookCollection
            .orderByChild("created_at", Query.Direction.DESCENDING)
            .equalTo(lastBook)
            .limitToFirst(10).get()
            .addOnSuccessListener {booksSnapshot ->
                if (!booksSnapshot.isEmpty) {
                    for (bookSnapShot in booksSnapshot.documents) {
                        val hashmap = bookSnapShot.data
                        hashmap?.put("id", bookSnapShot.id)
                        val bookData = Gson().toJson(hashmap)
                        val book = Gson().fromJson<Book>(bookData, Book::class.java)
                        adapter.addDatainList(book)
                    }
                }
            }
}