我正在开发一个应用程序，其中有recyclelerview，我必须在底部显示更多用户滚动加载更多数据。请帮我解决这个问题。
这是我的片段类，我在其中显示了Recycler View：
public class CDealAppListing extends Fragment {
public static String m_DealListingURL = "http://192.143.0.110:8080/ireward/rest/json/metallica/getDealListInJSON";
public static String s_szresult = " ";
public static RecyclerView m_RecyclerView;
public static CDealAppListingAdapter m_oAdapter;
public static CDealAppDatastorage item;
public ArrayList<CDealAppDatastorage> s_oDataset;
public int[] m_n_FormImage;
public View m_Main;
public CRegistrationSessionManagement m_oSessionManagement;
public String m_szMobileNumber, m_szEncryptedPassword;
public LinearLayoutManager mLayoutManager;
public RelativeLayout loadProgress;
public AppCompatButton m_showMore;
public ProgressBar mProgressBar;
int r = 4;
int u = 0;
String record = String.valueOf(r);
String last = String.valueOf(u);
//declare boolean
private CJsonsResponse m_oJsonsResponse;
@Nullable
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
m_Main = inflater.inflate(R.layout.deal_app_listing, container, false);//intialize mainLayout
new CDealDataSent().execute(m_DealListingURL);
init();//initialize method
implementScroll();
return m_Main;
}
public void init() {
mProgressBar = (ProgressBar) m_Main.findViewById(R.id.progressBar1);
mProgressBar.setVisibility(View.GONE);
m_showMore = (AppCompatButton) m_Main.findViewById(R.id.show_more);
m_showMore.setBackgroundColor(Color.TRANSPARENT);
m_showMore.setVisibility(View.INVISIBLE);
// Getting the string array from strings.xml
m_n_FormImage = new int[]{
R.drawable.amazon,
R.drawable.whatsapp,
R.drawable.zorpia,
R.drawable.path,
R.drawable.app_me,
R.drawable.evernote,
R.drawable.app_me};
m_RecyclerView = (RecyclerView) m_Main.findViewById(R.id.my_recycler_view);//finding id of recyclerview
m_RecyclerView.setItemAnimator(new DefaultItemAnimator());//setting default animation to recyclerview
m_RecyclerView.setHasFixedSize(true);//fixing size of recyclerview
//Layout manager for Recycler view
mLayoutManager = new LinearLayoutManager(getActivity());
m_RecyclerView.setLayoutManager(mLayoutManager);//showing odata vertically to user.
m_oSessionManagement = new CRegistrationSessionManagement(getActivity());
HashMap<String, String> user = m_oSessionManagement.getRegistrationDetails();
m_szEncryptedPassword = user.get(m_oSessionManagement.s_szKEY_PASSWORD);
m_szMobileNumber = user.get(m_oSessionManagement.s_szKEY_MOBILENUMBER);
}
public void implementScroll() {
m_RecyclerView.addOnScrollListener(new RecyclerView.OnScrollListener() {
@Override
public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
super.onScrolled(recyclerView, dx, dy);
if (dy > 0) {
m_showMore.setVisibility(View.VISIBLE);
m_showMore.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
//change boolean value
m_showMore.setVisibility(View.INVISIBLE);
r = r + 4;
u = u + 4;
record = String.valueOf(r);
last = String.valueOf(u);
new DealNext().execute(m_DealListingURL);
}
});
} else {
m_showMore.setVisibility(View.INVISIBLE);
}
}
});
}
//sending deal data to retreive response from server
public String DealListing(String url, CRegistrationDataStorage login) {
InputStream inputStream = null;
m_oJsonsResponse = new CJsonsResponse();
try {
// 1. create HttpClient
HttpClient httpclient = new DefaultHttpClient();
// 2. make POST request to the given URL
HttpPost httpPost = new HttpPost(url);
String json = "";
// 3. build jsonObject
JSONObject jsonObject = new JSONObject();
jsonObject.put("agentCode", "989899999");
jsonObject.put("pin", "05E0901648FD6439207FA74FC3E07734");
jsonObject.put("recordcount", record);
jsonObject.put("lastcountvalue", last);
//jsonObject.put("emailId", "nirajk1190@gmail.com");
// 4. convert JSONObject to JSON to String
json = jsonObject.toString();
// 5. set json to StringEntity
StringEntity se = new StringEntity(json);
// 6. set httpPost Entity
httpPost.setEntity(se);
// 7. Set some headers to inform server about the type of the content
httpPost.setHeader("Content-type", "application/json");
// 8. Execute POST request to the given URL
HttpResponse httpResponse = httpclient.execute(httpPost);
HttpEntity entity = httpResponse.getEntity();
// 9. receive response as inputStream
inputStream = entity.getContent();
System.out.println("InputStream....:" + inputStream.toString());
System.out.println("Response....:" + httpResponse.toString());
StatusLine statusLine = httpResponse.getStatusLine();
System.out.println("statusLine......:" + statusLine.toString());
////Log.d("resp_body", resp_body.toString());
int statusCode = statusLine.getStatusCode();
// 10. convert inputstream to string
if (statusCode == 200) {
// 10. convert inputstream to string
if (inputStream != null)
s_szresult = m_oJsonsResponse.convertInputStreamToString(inputStream);
//String resp_body =
EntityUtils.toString(httpResponse.getEntity());
} else
s_szresult = "Did not work!";
} catch (Exception e) {
Log.d("InputStream", e.getLocalizedMessage());
}
System.out.println("resul.....:" + s_szresult);
// 11. return s_szResult
return s_szresult;
}
// sending deal data to server and retreive response......
class CDealDataSent extends AsyncTask<String, Void, String> {
public JSONObject m_oResponseobject;
public ProgressDialog m_PDialog;
public CRegistrationDataStorage oRegisterStorage;
public CDealAppDatastorage item;
// @Override
protected void onPreExecute() {
super.onPreExecute();
m_PDialog = new ProgressDialog(getActivity());
m_PDialog.setMessage("Please wait while Loading Deals...");
m_PDialog.setCancelable(false);
m_PDialog.show();
}
@Override
protected String doInBackground(String... urls) {
return DealListing(urls[0], oRegisterStorage);// sending data to server...
}
// onPostExecute displays the results of the AsyncTask.
@Override
protected void onPostExecute(String result) {
m_PDialog.dismiss();
try {
m_oResponseobject = new JSONObject(result);// getting response from server
final JSONArray posts = m_oResponseobject.optJSONArray("dealList");
s_oDataset = new ArrayList<CDealAppDatastorage>();
for (int i = 0; i < posts.length(); i++) {
JSONObject post = posts.getJSONObject(i);
item = new CDealAppDatastorage();
item.setM_szHeaderText(post.getString("dealname"));
item.setM_szsubHeaderText(post.getString("dealcode"));
item.setM_n_Image(m_n_FormImage[i]);
s_oDataset.add(item);
}
if (m_oResponseobject.getString("resultdescription").equalsIgnoreCase("Transaction Successful")) {
m_oAdapter = new CDealAppListingAdapter(s_oDataset);//creating object of adapter and addd setting odata to adapter for use.
m_RecyclerView.setAdapter(m_oAdapter);//adding adapter to recyclerview
} else if (m_oResponseobject.getString("resultdescription").equalsIgnoreCase("Connection Not Available")) {
Toast.makeText(getActivity(), "Connection not avaliable", Toast.LENGTH_SHORT).show();
}
System.out.println("agentCode...." + m_szMobileNumber);
System.out.println("password...." + m_szEncryptedPassword);
System.out.println("record////" + record);
System.out.println("last:........" + last);
} catch (JSONException e) {
e.printStackTrace();
}
}
}
private class DealNext extends AsyncTask<String, Void, String> {
public JSONObject m_oResponseobject;
public CRegistrationDataStorage oRegisterStorage;
@Override
protected void onPreExecute() {
super.onPreExecute();
mProgressBar.setVisibility(View.VISIBLE);
}
@Override
protected String doInBackground(String... urls) {
//My Background tasks are written here
synchronized (this) {
return DealListing(urls[0], oRegisterStorage);
}
}
@Override
protected void onPostExecute(String result) {
mProgressBar.setVisibility(View.INVISIBLE);
super.onPostExecute(result);
try {
m_oResponseobject = new JSONObject(result);// getting response from server
final JSONArray posts = m_oResponseobject.optJSONArray("dealList");
s_oDataset = new ArrayList<CDealAppDatastorage>();
for (int i = 0; i < posts.length(); i++) {
JSONObject post = posts.getJSONObject(i);
item = new CDealAppDatastorage();
item.setM_szHeaderText(post.getString("dealname"));
item.setM_szsubHeaderText(post.getString("dealcode"));
item.setM_n_Image(m_n_FormImage[i]);
s_oDataset.add(item);
}
if (m_oResponseobject.getString("resultdescription").equalsIgnoreCase("Transaction Successful")) {
m_oAdapter = new CDealAppListingAdapter(s_oDataset);//creating object of adapter and addd setting odata to adapter for use.
m_RecyclerView.setAdapter(m_oAdapter);//adding adapter to recyclerview
} else if (m_oResponseobject.getString("resultdescription").equalsIgnoreCase("Connection Not Available")) {
Toast.makeText(getActivity(), "Connection not avaliable", Toast.LENGTH_SHORT).show();
}
System.out.println("agentCode...." + m_szMobileNumber);
System.out.println("password...." + m_szEncryptedPassword);
System.out.println("record////" + record);
System.out.println("last:........" + last);
} catch (JSONException e) {
e.printStackTrace();
}
}
}
}
And here is Adapter class:-
public class CDealAppListingAdapter extends RecyclerView.Adapter<CDealAppListingAdapter.DealAppViewHolder> {
private static ArrayList<CDealAppDatastorage> s_oDataset;
public CDealAppListingAdapter(ArrayList<CDealAppDatastorage> mDataList) {
s_oDataset = mDataList;
}
@Override
public int getItemViewType(int position) {
return super.getItemViewType(position);
}
@Override
public DealAppViewHolder onCreateViewHolder(ViewGroup viewGroup, int i) {
View itemLayoutView = LayoutInflater.from(viewGroup.getContext()).inflate(R.layout.deallisting_card_view, viewGroup, false);
DealAppViewHolder viewHolder = new DealAppViewHolder(itemLayoutView);//creating object of ViewHolder containg component
return viewHolder;
}
@Override
public void onBindViewHolder(DealAppViewHolder viewHolder, int i) {
CDealAppDatastorage list = s_oDataset.get(i);// receiving item on position on index i
DealAppViewHolder.s_szAppImage.setImageResource(list.getM_n_Image());//adding m_n_Image to viewHolder
DealAppViewHolder.s_szheadingText.setText(list.getM_szHeaderText());
DealAppViewHolder.s_szSubHeader.setText(list.getM_szsubHeaderText());
viewHolder.m_oDealAppDatastorage = list;
}
@Override
public int getItemCount() {
return (null != s_oDataset ? s_oDataset.size() : 0);//counting size of odata in ArrayList
}
public static class DealAppViewHolder extends RecyclerView.ViewHolder {
public static ImageView s_szAppImage;
public static TextView s_szheadingText, s_szSubHeader;
public static Button s_szGetDealBtn;
public CDealAppDatastorage m_oDealAppDatastorage;
public DealAppViewHolder(View itemLayoutView) {
super(itemLayoutView);
s_szheadingText = (TextView) itemLayoutView.findViewById(R.id.headingText);// finding id of headerText...
s_szSubHeader = (TextView) itemLayoutView.findViewById(R.id.subHeaderText);// finding id of subHeader.....
s_szAppImage = (ImageView) itemLayoutView.findViewById(R.id.appImage);//finding Id of Imgae in CardView
s_szGetDealBtn = (Button) itemLayoutView.findViewById(R.id.getDealBtn);// finding id of getdeal Btn
Random rnd = new Random();//creating object of Random class
int color = Color.argb(255, rnd.nextInt(256), rnd.nextInt(256), rnd.nextInt(256));//genrating random color
s_szGetDealBtn.setBackgroundColor(color);//backgraound color of getDeal Btn
s_szGetDealBtn.setOnClickListener(new View.OnClickListener() {// onclick getDeal Btn
@Override
public void onClick(View v) {//send to deal detail page onclick getDeal Btn
Intent i = new Intent(v.getContext(), CDealAppListingDetails.class);
Bundle b = new Bundle();
b.putSerializable("DATA", s_oDataset.get(getPosition()));// sending data to deal detail page
i.putExtras(b);
v.getContext().startActivity(i);
}
});
itemLayoutView.setOnClickListener(new View.OnClickListener() {// onclick cardview
@Override
public void onClick(View v) {// onclick cardview send to deal app listing details page .....
Intent i = new Intent(v.getContext(), CDealAppListingDetails.class);
Bundle b = new Bundle();
b.putSerializable("DATA", s_oDataset.get(getPosition()));
i.putExtras(b);
v.getContext().startActivity(i);
}
});
}
}
}
答案 0 :(得分：0)
我是如何实现类似的东西的，我在名为'加载更多'的RecyclerView中添加了一个页脚，然后点击加载更多页脚我再次调用服务以获取更多数据，然后通知Recycler视图重新填充数据。
那么让我讨论一下我的服务器端实现。当第一次加载RecyclerView时，我调用了一个服务来从服务器获取页码为0的数据。当收到响应时，我填充了RecyclerView并在最后添加了一个加载更多的页脚RecyclerView。当单击加载更多页脚时，我再次使用页码1调用该服务，当我收到响应时，我将数据与先前保存的列表相加，然后在notifyDataSetChanged上调用Adapter。这就是我的情况下如何进行简单的分页。
我必须在服务器的每个响应中放置一个boolean，表明我是否还有更多数据要显示。因此，当发现布尔hasNext为false时，我必须将加载更多页脚的文本更改为“不再显示结果”，以便用户可以理解不再有数据。