问题：
如何在recyclerview中显示更多数据，并在recyclerview下方显示进度条
隆向晨
我想要一个recyclerview，当第一个应用程序打开时，然后在创建时从服务器获取一些数据，当向上滚动时，会显示recyclerview下方的进度条，当向上滚动到服务器时再次点击URL，并在先前获取的数据下方获取更多数据。但我知道当我第二次点击URL时，它会刷新页面，并在第二次点击时只显示从服务器获取的数据，但我想要第一次和第二次点击的响应。
对不起，我说英语
以下是我的主要活动代码：
public class MainActivity extends AppCompatActivity {
public static String m_DealListingURL = "http://192.163.0.110:8080/ireward/rest/json/metallica/getDealListInJSON";
public static String s_szresult = " ";
public CJsonsResponse m_oJsonsResponse;
public int[] m_n_FormImage;
public String sz_RecordCount, sz_LastCount;
public int m_n_DefaultRecordCount = 5;// intiallly record count is 5.
public int m_n_DeafalutLastCount = 0;//initally lastcount is 0.
boolean isFirstTime;
private Toolbar mToolbar;
private RecyclerView mRecyclerView;
private List<User> mUsers = new ArrayList<>();
private UserAdapter mUserAdapter;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mToolbar = (Toolbar) findViewById(R.id.toolbar);
mToolbar.setTitle("LoadMoreRecycleView");
isFirstTime = true;
//..............sending first hit ..................................
new CDealDataSent().execute(m_DealListingURL);
mRecyclerView = (RecyclerView) findViewById(R.id.recycleView);
sz_RecordCount = String.valueOf(m_n_DefaultRecordCount);// increment of record count
sz_LastCount = String.valueOf(m_n_DeafalutLastCount);
mRecyclerView.setLayoutManager(new LinearLayoutManager(this));
mUserAdapter = new UserAdapter();
mRecyclerView.setAdapter(mUserAdapter);
// 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};
mUserAdapter.setOnLoadMoreListener(new OnLoadMoreListener() {
@Override
public void onLoadMore() {
Log.e("haint", "Load More");
mUsers.add(null);
mUserAdapter.notifyItemInserted(mUsers.size() - 1);
//Load more data for reyclerview
new Handler().postDelayed(new Runnable() {
// @Override
public void run() {
Log.e("haint", "Load More 2");
mUsers.remove(mUsers.size() - 1);
mUserAdapter.notifyItemRemoved(mUsers.size());
m_n_DefaultRecordCount = m_n_DefaultRecordCount + 5;
m_n_DeafalutLastCount = m_n_DeafalutLastCount + 5;
sz_RecordCount = String.valueOf(m_n_DefaultRecordCount);
sz_LastCount = String.valueOf(m_n_DeafalutLastCount);
//...........sending second hit ./.................
new DealNext().execute(m_DealListingURL);
mUserAdapter.setLoaded();
}
}, 5000);
}
});
}
public String DealListing(String url, CRegistrationDataStorage login) {
//sending deal data to retreive response from server
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", "9555517456");
jsonObject.put("pin", "05E0901648FD6439207FA74FC3E07734");
jsonObject.put("recordcount", sz_RecordCount);
jsonObject.put("lastcountvalue", sz_LastCount);
//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;
}
static class UserViewHolder extends RecyclerView.ViewHolder {
public TextView tvName;
public TextView tvEmailId;
public ImageView appImage;
public UserViewHolder(View itemView) {
super(itemView);
tvName = (TextView) itemView.findViewById(R.id.tvName);
appImage = (ImageView) itemView.findViewById(R.id.appImage);
tvEmailId = (TextView) itemView.findViewById(R.id.tvEmailId);
}
}
static class LoadingViewHolder extends RecyclerView.ViewHolder {
public ProgressBar progressBar;
public LoadingViewHolder(View itemView) {
super(itemView);
progressBar = (ProgressBar) itemView.findViewById(R.id.progressBar1);
}
}
class CDealDataSent extends AsyncTask<String, Void, String> {
// sending first hit to server ........................................
public JSONObject m_oResponseobject;
public ProgressDialog m_PDialog;
public CRegistrationDataStorage oRegisterStorage;
public User item;
// @Override
protected void onPreExecute() {
super.onPreExecute();
m_PDialog = new ProgressDialog(MainActivity.this);
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");
mUsers = new ArrayList<User>();
for (int i = 0; i < posts.length(); i++) {
JSONObject post = posts.getJSONObject(i);
item = new User();
item.setName(post.getString("dealname"));
item.setEmail(post.getString("dealcode"));
item.setImage(m_n_FormImage[i]);
mUsers.add(item);
}
getResponse();
} catch (JSONException e) {
e.printStackTrace();
}
}
public void getResponse() throws JSONException {
if (m_oResponseobject.getString("resultdescription").equalsIgnoreCase("Transaction Successful")) {
mUserAdapter = new UserAdapter();//creating object of adapter and addd setting odata to adapter for use.
mRecyclerView.setAdapter(mUserAdapter);//adding adapter to recyclerview
} else if (m_oResponseobject.getString("resultdescription").equalsIgnoreCase("Connection Not Available")) {
Toast.makeText(MainActivity.this, "Connection not avaliable", Toast.LENGTH_SHORT).show();
}
}
}
// sending second time hit to server..................................
// ...................................................................................
private class DealNext extends AsyncTask<String, Void, String> {
public JSONObject m_oResponseobject;
public CRegistrationDataStorage oRegisterStorage;
public User item;
@Override
protected void onPreExecute() {
super.onPreExecute();
}
@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) {
super.onPostExecute(result);
try {
m_oResponseobject = new JSONObject(result);// getting response from server
if (m_oResponseobject.getString("resultdescription").equalsIgnoreCase("Deal List Not Found"))
return;
final JSONArray posts = m_oResponseobject.optJSONArray("dealList");
if (isFirstTime) {
mUsers = new ArrayList<User>();
isFirstTime = false;
} else {
mUsers.remove(mUsers.size() - 1);
mUserAdapter.notifyItemRemoved(mUsers.size());
}
for (int i = 0; i < posts.length(); i++) {
JSONObject post = posts.getJSONObject(i);
item = new User();
item.setName(post.getString("dealname"));
item.setEmail(post.getString("dealcode"));
item.setImage(m_n_FormImage[i]);
mUsers.add(item);
// m_oAdapter.notifyDataSetChanged();
mUserAdapter.notifyItemInserted(mUsers.size());
mUserAdapter.setLoaded();
}
if (m_oResponseobject.getString("resultdescription").equalsIgnoreCase("Transaction Successful")) {
mUserAdapter = new UserAdapter();//creating object of adapter and addd setting odata to adapter for use.
mRecyclerView.setAdapter(mUserAdapter);//adding adapter to recyclerview
} else if (m_oResponseobject.getString("resultdescription").equalsIgnoreCase("Connection Not Available")) {
Toast.makeText(MainActivity.this, "Connection not avaliable", Toast.LENGTH_SHORT).show();
}
} catch (JSONException e) {
e.printStackTrace();
}
}
}
class UserAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder> {
private final int VIEW_TYPE_ITEM = 0;
private final int VIEW_TYPE_LOADING = 1;
private OnLoadMoreListener mOnLoadMoreListener;
private boolean isLoading;
private int visibleThreshold = 5;
private int lastVisibleItem, totalItemCount;
public UserAdapter() {
final LinearLayoutManager linearLayoutManager = (LinearLayoutManager) mRecyclerView.getLayoutManager();
mRecyclerView.addOnScrollListener(new RecyclerView.OnScrollListener() {
@Override
public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
super.onScrolled(recyclerView, dx, dy);
totalItemCount = linearLayoutManager.getItemCount();
lastVisibleItem = linearLayoutManager.findLastVisibleItemPosition();
if (!isLoading && totalItemCount <= (lastVisibleItem + visibleThreshold)) {
if (mOnLoadMoreListener != null) {
mOnLoadMoreListener.onLoadMore();
}
isLoading = true;
}
}
});
}
public void setOnLoadMoreListener(OnLoadMoreListener mOnLoadMoreListener) {
this.mOnLoadMoreListener = mOnLoadMoreListener;
}
@Override
public int getItemViewType(int position) {
return mUsers.get(position) == null ? VIEW_TYPE_LOADING : VIEW_TYPE_ITEM;
}
@Override
public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
if (viewType == VIEW_TYPE_ITEM) {
View view = LayoutInflater.from(MainActivity.this).inflate(R.layout.layout_user_item, parent, false);
return new UserViewHolder(view);
} else if (viewType == VIEW_TYPE_LOADING) {
View view = LayoutInflater.from(MainActivity.this).inflate(R.layout.layout_loading_item, parent, false);
return new LoadingViewHolder(view);
}
return null;
}
@Override
public void onBindViewHolder(RecyclerView.ViewHolder holder, int position) {
if (holder instanceof UserViewHolder) {
User user = mUsers.get(position);
UserViewHolder userViewHolder = (UserViewHolder) holder;
userViewHolder.tvName.setText(user.getName());
userViewHolder.tvEmailId.setText(user.getEmail());
userViewHolder.appImage.setImageResource(user.getImage());
} else if (holder instanceof LoadingViewHolder) {
LoadingViewHolder loadingViewHolder = (LoadingViewHolder) holder;
loadingViewHolder.progressBar.setIndeterminate(true);
}
}
@Override
public int getItemCount() {
return mUsers == null ? 0 : mUsers.size();
}
public void setLoaded() {
isLoading = false;
}
}
}
暂时还没有答案
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