diff --git a/app/src/main/java/io/legado/app/ui/main/bookshelf/books/BooksFragment.kt b/app/src/main/java/io/legado/app/ui/main/bookshelf/books/BooksFragment.kt index a1390dc94..a7b714bed 100644 --- a/app/src/main/java/io/legado/app/ui/main/bookshelf/books/BooksFragment.kt +++ b/app/src/main/java/io/legado/app/ui/main/bookshelf/books/BooksFragment.kt @@ -7,6 +7,7 @@ import androidx.lifecycle.Observer import androidx.recyclerview.widget.DiffUtil import androidx.recyclerview.widget.GridLayoutManager import androidx.recyclerview.widget.LinearLayoutManager +import androidx.recyclerview.widget.RecyclerView import io.legado.app.App import io.legado.app.R import io.legado.app.base.BaseFragment @@ -27,6 +28,7 @@ import io.legado.app.utils.getViewModelOfActivity import io.legado.app.utils.observeEvent import kotlinx.android.synthetic.main.fragment_books.* import org.jetbrains.anko.startActivity +import kotlin.math.max class BooksFragment : BaseFragment(R.layout.fragment_books), @@ -75,6 +77,23 @@ class BooksFragment : BaseFragment(R.layout.fragment_books), booksAdapter = BooksAdapterGrid(requireContext(), this) } rv_bookshelf.adapter = booksAdapter + booksAdapter.registerAdapterDataObserver(object : RecyclerView.AdapterDataObserver() { + override fun onItemRangeInserted(positionStart: Int, itemCount: Int) { + val layoutManager = rv_bookshelf.layoutManager + if (positionStart == 0 && layoutManager is LinearLayoutManager) { + val scrollTo = layoutManager.findFirstVisibleItemPosition() - itemCount + rv_bookshelf.scrollToPosition(max(0, scrollTo)) + } + } + + override fun onItemRangeMoved(fromPosition: Int, toPosition: Int, itemCount: Int) { + val layoutManager = rv_bookshelf.layoutManager + if (toPosition == 0 && layoutManager is LinearLayoutManager) { + val scrollTo = layoutManager.findFirstVisibleItemPosition() - itemCount + rv_bookshelf.scrollToPosition(max(0, scrollTo)) + } + } + }) } private fun upRecyclerData() {