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您好，我试图在 recylerview 中包含分页，我想要的是在片段开始时加载 10 个图像，当可见项目达到 5 个项目计数（适配器中仍有 5 个项目）时，下一个 5 将加载到适配器中，动机这样做是我不想显示进度条

当可见项目数达到 5 时，适配器中总共加载了 10 个图像，接下来 5 个将加载到适配器中，因此适配器将维护 10 个项目并重复循环

注意：- 我一次实现了一个项目滚动，这意味着一次只能滚动一个图像

我现在力图实施任何分页方法

Home_Fragment.java

 public List<Upload> mUploads;
    PostAdapter_Home postsAdapter;
    RecyclerView verticalRecyclerView;
    ShimmerFrameLayout shimmerFrameLayout;

    @SuppressLint("SourceLockedOrientationActivity")
    @Nullable
    @Override
    public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
        View view = inflater.inflate(R.layout.fragment_home, container, false);
        requireActivity().setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_PORTRAIT);
        MaterialToolbar materialToolbar = view.findViewById(R.id.toolbar);
        materialToolbar.setOnMenuItemClickListener(toolbarItemClickListener);
        verticalRecyclerView = view.findViewById(R.id.recyclerViewHome);
        shimmerFrameLayout = view.findViewById(R.id.shimmerEffect);

//        this is for one item per scroll
        SnapHelper snapHelper = new PagerSnapHelper();
        snapHelper.attachToRecyclerView(verticalRecyclerView);

        verticalRecyclerView.setLayoutManager(
                new StaggeredGridLayoutManager(1, StaggeredGridLayoutManager.VERTICAL)
        );

        getData();
        shimmerFrameLayout.startShimmer();
        mUploads = new ArrayList<>();
        postsAdapter = new PostAdapter_Home(getContext(), mUploads);
        verticalRecyclerView.setAdapter(postsAdapter);
        verticalRecyclerView.scrollToPosition(Home_Fragment.saved_position);
        return view;
    }


    private void getData() {
        databaseReference.addValueEventListener(new ValueEventListener() {
            @Override
            public void onDataChange(@NonNull DataSnapshot snapshot) {
                if (snapshot.exists()) {
                    shimmerFrameLayout.stopShimmer();
                    shimmerFrameLayout.setVisibility(View.GONE);
                    verticalRecyclerView.setVisibility(View.VISIBLE);
                    mUploads.clear();
                    for (DataSnapshot dataSnapshot : snapshot.getChildren()) {
                        Upload upload = dataSnapshot.getValue(Upload.class);
                        assert upload != null;
                        upload.setmKey(dataSnapshot.getKey());
                        mUploads.add(upload);


                    }

                }

                //notify the adapter
                postsAdapter.notifyDataSetChanged();
            }

            @Override
            public void onCancelled(@NonNull DatabaseError error) {
            }
        });
    }
}
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