我有一个片段，其中onCreateView方法向服务器发送请求并获取一些数据。这工作正常但是当我在onResume中发送另一个请求时，它会使列表视图中的数据加倍。我该如何解决这个问题？
代码：
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
m_Main = inflater.inflate(R.layout.deal_listing, container, false);//intialize mainLayout
getDetails();// get deatail of user from sharedpreference......
init();//initialize metho
return m_Main;
}
private void getDetails() {// get details of user from shared preference...
CLoginSessionManagement m_oSessionManagement = new CLoginSessionManagement(getActivity());// crating object of Login Session
HashMap<String, String> user = m_oSessionManagement.getLoginDetails();// get String from Login Session
m_szMobileNumber = user.get(CLoginSessionManagement.s_szKEY_MOBILE).trim();// getting password from saved preferences..........
m_szEncryptedPassword = user.get(CLoginSessionManagement.s_szKEY_PASSWORD).trim();// getting mobile num from shared preferences...
sz_RecordCount = String.valueOf(m_n_DefaultRecordCount);// increment of record count
sz_LastCount = String.valueOf(m_n_DeafalutLastCount);// increment of last count...
s_oDataset = new ArrayList<>();// making object of Arraylist
if (NetworkUtil.isConnected(getActivity())) {
postDealListingDatatoServer();// here sending request in onCreate
} else {
Toast.makeText(getActivity(), "Please check internet connection !", Toast.LENGTH_LONG).show();
}
}
@Override
public void onResume() {
super.onResume();
if (NetworkUtil.isConnected(getActivity())) {
postDealListingDatatoServer();// here in on Resume send request which double data
} else {
Toast.makeText(getActivity(), "Please check internet connection !", Toast.LENGTH_LONG).show();
}
}
private void init() {// initialize controls
m_ProgressBar = (ProgressBar) m_Main.findViewById(R.id.progressBar1);// finding Id of progressview
m_ProgressBar.setVisibility(View.GONE);// make profressView Invisible first time
/*Swipe to refresh code*/
mSwipeRefresh = (SwipeRefreshLayout) m_Main.findViewById(R.id.mainLayout);
mSwipeRefresh.setColorSchemeResources(R.color.refresh_progress_1);
mSwipeRefresh.setOnRefreshListener(new SwipeRefreshLayout.OnRefreshListener() {
@Override
public void onRefresh() {
/*Here check net connection avialable or not */
if (NetworkUtil.isConnected(getActivity())) {
m_ListView.removeFooterView(btnLoadMore);
s_oDataset.clear();
m_n_DeafalutLastCount = 0;
sz_LastCount = String.valueOf(m_n_DeafalutLastCount);// convert int value to string /////
swipeData();
} else {
Toast.makeText(getActivity(), "Please check internet connection !", Toast.LENGTH_LONG).show();
if (mSwipeRefresh.isRefreshing()) {
mSwipeRefresh.setRefreshing(false);
}
}
}
});
m_n_FormImage = new int[]{// defining Images in Integer array
R.drawable.amazon,
R.drawable.whatsapp,
R.drawable.zorpia,
R.drawable.path,
R.drawable.app_me,
R.drawable.evernote,
R.drawable.app_me};
m_ListView = (ListView) m_Main.findViewById(R.id.dealList);// findind Id of Listview
m_ListView.setFadingEdgeLength(0);
m_ListView.setOnScrollListener(new AbsListView.OnScrollListener() {
@Override
public void onScrollStateChanged(AbsListView view, int scrollState) {
}
@Override
public void onScroll(AbsListView view, int firstVisibleItem, int visibleItemCount, int totalItemCount) {
if (firstVisibleItem == 0) {
mSwipeRefresh.setEnabled(true);
} else {
mSwipeRefresh.setEnabled(false);
}
}
});
}
/*This is new changes in code ....using Volley instead of AsynkTask*/
/*This method send request to server for deallisting*/
// this method send request to server for deal list....
public void postDealListingDatatoServer() {
try {
String json;
// 3. build jsonObject
JSONObject jsonObject = new JSONObject();// making object of Jsons.
jsonObject.put("agentCode", m_szMobileNumber);// put mobile number
jsonObject.put("pin", m_szEncryptedPassword);// put password
jsonObject.put("recordcount", sz_RecordCount);// put record count
jsonObject.put("lastcountvalue", sz_LastCount);// put last count
// 4. convert JSONObject to JSON to String
json = jsonObject.toString();// convert Json object to string
System.out.println("Request:-" + json);
m_Dialog = DialogUtils.showProgressDialog(getActivity(), "Please wait while loading deals...");
JsonObjectRequest jsonObjectRequest = new JsonObjectRequest(Request.Method.POST, CServerAPI.m_DealListingURL, jsonObject, new Response.Listener<JSONObject>() {
@Override
public void onResponse(JSONObject response) {
System.out.println("Response:-" + response);
m_Dialog.dismiss();
try {
JSONArray posts = response.optJSONArray("dealList");// get Deal list in array from response
for (int i = 0; i < posts.length(); i++) {// loop for counting deals from server
JSONObject post = posts.getJSONObject(i);// counting deal based on index
item = new CDealAppDatastorage();// creating object of DealAppdata storage
item.setM_szHeaderText(post.getString("dealname"));// get deal name from response
item.setM_szsubHeaderText(post.getString("dealcode"));// get dealcode from response
item.setM_szDealValue(post.getString("dealvalue"));// get deal value from response
item.setM_n_Image(m_n_FormImage[i]);//set Image Index wise(Dummy)
s_oDataset.add(item);// add all items in ArrayList
}
// LoadMore button
btnLoadMore = new Button(getActivity());// creating button
btnLoadMore.setText("LOAD MORE DEALS");// set Text in Button
btnLoadMore.setBackgroundResource(R.drawable.button_boarder);// set Background Resource
btnLoadMore.setTypeface(Typeface.DEFAULT_BOLD);
btnLoadMore.setTextSize(14);
btnLoadMore.setTextColor(Color.WHITE);// set Color of button text
btnLoadMore.setGravity(Gravity.CENTER);// set Gravity of button text
if (!s_oDataset.isEmpty()) {// condition if data in arraylist is not empty
// Adding Load More button to lisview at bottom
m_ListView.addFooterView(btnLoadMore);// add footer in listview
m_oAdapter = new CDealAppListingAdapter(getActivity(), s_oDataset);// create adapter object and add arraylist to adapter
m_ListView.setAdapter(m_oAdapter);//adding adapter to recyclerview
} else {
btnLoadMore.setVisibility(View.GONE);// else Load buttonvisibility set to Gone
}
btnLoadMore.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {// load more button onclick listener
if (NetworkUtil.isConnected(getActivity())) {
m_n_DefaultRecordCount = 5;// increment of record count by 5 on next load data
m_n_DeafalutLastCount = m_n_DeafalutLastCount + 5;// same here.....as above
String itemscount = String.valueOf(m_ListView.getAdapter().getCount());
System.out.println("Toatal item:-" + itemscount);
sz_RecordCount = String.valueOf(m_n_DefaultRecordCount);// convert int value to string
sz_LastCount = String.valueOf(m_n_DeafalutLastCount);// convert int value to string /////
loadmoreData();
} else {
Toast.makeText(getActivity(), "Please check internet connection !", Toast.LENGTH_LONG).show();
}
}
});
if (response.getString("resultdescription").equalsIgnoreCase("Connection Not Available")) {//server based conditions
CSnackBar.getInstance().showSnackBarError(m_Main.findViewById(R.id.mainLayout), "Connection Lost !", getActivity());
} else if (response.getString("resultdescription").equalsIgnoreCase("Deal List Not Found")) {// serevr based conditions .....
CSnackBar.getInstance().showSnackBarError(m_Main.findViewById(R.id.mainLayout), "No more deals available", getActivity());
} else if (response.getString("resultdescription").equalsIgnoreCase("Technical Failure")) {
CSnackBar.getInstance().showSnackBarError(m_Main.findViewById(R.id.mainLayout), "Technical Failure", getActivity());
}
} catch (JSONException e) {
e.printStackTrace();
}
}
}, new Response.ErrorListener() {
@Override
public void onErrorResponse(VolleyError error) {
System.out.println("Errror:-" + error);
m_Dialog.dismiss();
if (error instanceof TimeoutError) {
CSnackBar.getInstance().showSnackBarError(m_Main.findViewById(R.id.mainLayout), "Connection lost ! Please try again", getActivity());
} else if (error instanceof NetworkError) {
CSnackBar.getInstance().showSnackBarError(m_Main.findViewById(R.id.mainLayout), "No internet connection", getActivity());
}
}
});
RequestQueue requestQueue = Volley.newRequestQueue(getActivity());
requestQueue.add(jsonObjectRequest);
} catch (JSONException e) {
e.printStackTrace();
}
}
答案 0 :(得分：0)
请从正在调用postDealListingDatatoServer（）的onCreateView中删除调用getDetails（）。从onResume
调用getDetails（）方法你现在可以删除onResume（）中的if-else块，只需从onResume调用getDetails（）
另一种方法是，在调用postDealListingDatatoServer（）之前清除s_oDataset，这样可以避免向列表中添加相同的数据
答案 1 :(得分：0)
onResume（）总是在onCreate（）之后调用，所以没有理由让它们做同样的事情。只需实现onResume来调用数据更新代码而不是onCreate（）
答案 2 :(得分：0)
在向其添加新数据之前，您应该清除s_oDataset。
你可以这样做：
JSONArray posts = response.optJSONArray("dealList");// get Deal list in array from response
s_oDataset.clear(); // clear the old values
for (int i = 0; i < posts.length(); i++) {// loop for counting deals from server
JSONObject post = posts.getJSONObject(i);// counting deal based on index
item = new CDealAppDatastorage();// creating object of DealAppdata storage
item.setM_szHeaderText(post.getString("dealname"));// get deal name from response
item.setM_szsubHeaderText(post.getString("dealcode"));// get dealcode from response
item.setM_szDealValue(post.getString("dealvalue"));// get deal value from response
item.setM_n_Image(m_n_FormImage[i]);//set Image Index wise(Dummy)
s_oDataset.add(item);// add all items in ArrayList
}
要防止Button加倍，而不是：
m_ListView.addFooterView(btnLoadMore);
您可以检查ListView是否有FooterView并相应地创建Button：
if(m_ListView.getFooterViewsCount() == 0) {
btnLoadMore = new Button(getActivity());// creating button
btnLoadMore.setText("LOAD MORE DEALS");// set Text in Button
btnLoadMore.setBackgroundResource(R.drawable.button_boarder);// set Background Resource
btnLoadMore.setTypeface(Typeface.DEFAULT_BOLD);
btnLoadMore.setTextSize(14);
btnLoadMore.setTextColor(Color.WHITE);// set Color of button text
btnLoadMore.setGravity(Gravity.CENTER);
m_ListView.addFooterView(btnLoadMore);
}