试试这个：
public class home extends AppCompatActivity { //a list to store all the products List<Product> productList; //the recyclerview RecyclerView recyclerView; adepter a; ProgressBar Pbar; GridLayoutManager manager; int token = 1; Boolean isScrolling = false; int currentItems, totalItems, scrollOutItems; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_home); Pbar = findViewById(R.id.progressBar1); //getting the recyclerview from xml recyclerView = findViewById(R.id.recylcerView); recyclerView.setHasFixedSize(true); manager = new GridLayoutManager(this, 2); recyclerView.setLayoutManager(manager); //initializing the productlist productList = new ArrayList<>(); a = new adepter(home.this, productList); recyclerView.setAdapter(a); recyclerView.addonScrollListener(new RecyclerView.onScrollListener() { @Override public void onScrollStateChanged(RecyclerView recyclerView, int newState) { super.onScrollStateChanged(recyclerView, newState); if(newState == AbsListView.OnScrollListener.SCROLL_STATE_TOUCH_SCROLL) { isScrolling = true; } } @Override public void onScrolled(RecyclerView recyclerView, int dx, int dy) { super.onScrolled(recyclerView, dx, dy); currentItems = manager.getChildCount(); totalItems = manager.getItemCount(); scrollOutItems = manager.findFirstVisibleItemPosition(); if(isScrolling && (currentItems + scrollOutItems == totalItems)) { isScrolling = false; token++; getData(); } } }); getData(); } private void getData(){ String url = "https://shop.com/index.php"; url = url+ "&pg="+ String.valueOf(token); Pbar.setVisibility(View.VISIBLE); StringRequest stringRequest = new StringRequest(Request.Method.GET, url, new Response.Listener<String>() { @Override public void onResponse(String response) { // Toast.makeText(getApplicationContext(),"volly ok ",Toast.LENGTH_LONG).show(); try { //converting the string to json array object JSonArray array = new JSonArray(response); //traversing through all the object for (int i = 0; i < array.length(); i++) { //getting product object from json array JSonObject product = array.getJSonObject(i); //adding the product to product list productList.add(new Product( product.getInt("id"), product.getString("title"), product.getString("shortdesc"), product.getString("type"), product.getString("price"), product.getString("image") )); } a.notifyDataSetChanged(); Pbar.setVisibility(View.GONE); } catch (JSonException e) { e.printStackTrace(); } } }, new Response.ErrorListener() { @Override public void onErrorResponse(VolleyError error) { Toast.makeText(getApplicationContext(), "Server Error" ,Toast.LENGTH_LONG).show(); } }); //adding our stringrequest to queue Volley.newRequestQueue(this).add(stringRequest); }}
