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我正在構建一個像techcrunch一樣的應用程序。我從JSON格式的服務器獲取數據，並在列表視圖中顯示數據，如文章標題，作者姓名和圖像。當用戶在列表視圖中滾動更多文章時，我應用了分頁方式。我的分頁工作正常，但滾動功能存在問題，因爲新數據或新數據加載的滾動劑量與數據不一致。爲了澄清更簡單的話我的滾動兒去的時候我其實向下滾動此頁面的頂部是我的代碼：如何在列表視圖中實現正確的滾動以在分段活動上實現分頁？
public class OneFragment extends Fragment {
public OneFragment(){}
private static final String TAG = OneFragment.class.getSimpleName();
// Movies json url
private static String URL = "http:url&page=1";
private ProgressDialog pDialog;
private List<Movie> movieList = new ArrayList<Movie>();
private ListView listView;
private CustomListAdapter adapter;
int current_page = 1;
int mPreLast;
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
final View rootView = inflater.inflate(R.layout.swip, container, false);
pDialog = new ProgressDialog(getActivity());
pDialog.setMessage("Loading...");
pDialog.show();
pDialog.setCancelable(false);
listView = (ListView) rootView.findViewById(R.id.list49);
listView.setOnScrollListener(new AbsListView.OnScrollListener()
{
@Override
public void onScrollStateChanged(AbsListView absListView, int i)
{
}
@Override
public void onScroll(AbsListView view, int firstVisibleItem, int visibleItemCount, int totalItemCount)
{
int lastItem = firstVisibleItem + visibleItemCount;
if(lastItem == totalItemCount){
if (mPreLast != lastItem)
{
mPreLast = lastItem;
onStart();
}
}
}
});
listView.setOnItemClickListener(new OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> adapterView, View view, int Position,
long offset) {
// TODO Auto-generated method stub
Movie item = (Movie) adapter.getItem(Position);
Intent intent = new Intent(rootView.getContext(), SingleArticle.class);
single.date = item.getDate();
single.id = item.getId();
startActivity(intent);
}
});
//pDialog = new ProgressDialog(this);
// Showing progress dialog before making http request
return rootView;
}
@Override
public void onStart(){
super.onStart();
// calling adapter changes here, just
// to avoid getactivity()null
// increment current page
current_page += 1;
// Next page request
URL = "http:url&page=" + current_page;
//adapter = new CustomListAdapter(this, movieList);
// changing action bar color
//getActivity().getActionBar().setBackground(
//new ColorDrawable(Color.parseColor("#1b1b1b")));
// Creating volley request obj
JsonArrayRequest movieReq = new JsonArrayRequest(URL,
new Response.Listener<JSONArray>() {
@Override
public void onResponse(JSONArray response) {
Log.d(TAG, response.toString());
hidePDialog();
// Parsing json
for (int i = 0; i < response.length(); i++) {
try {
JSONObject obj = response.getJSONObject(i);
Movie movie = new Movie();
movie.setDate(obj.getString("date"));
movie.setId(obj.getString("id"));
movieList.add(movie);
int currentPosition = listView.getFirstVisiblePosition();
adapter = new CustomListAdapter(getActivity(), movieList);
adapter.notifyDataSetChanged();
listView.setAdapter(adapter);
listView.setSelectionFromTop(currentPosition + 1, 0);
} catch (JSONException e) {
e.printStackTrace();
}
}
}
},new Response.ErrorListener() {
@Override
public void onErrorResponse(VolleyError error) {
VolleyLog.d(TAG, "Error: " + error.getMessage());
new AlertDialog.Builder(getActivity())
.setTitle("No Connectivity ")
.setMessage("Please check your internet connectivity!")
.setPositiveButton(android.R.string.yes, new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
// continue with delete
}
})
//.setNegativeButton(android.R.string.no, new DialogInterface.OnClickListener() {
//public void onClick(DialogInterface dialog, int which) {
// do nothing
//}
//})
.setIcon(android.R.drawable.ic_dialog_alert)
.show();
hidePDialog();
}
});
AppController.getInstance().addToRequestQueue(movieReq);
listView.setAdapter(adapter);
}
private View getActionBar() {
// TODO Auto-generated method stub
return null;
}
@Override
public void onDestroy() {
super.onDestroy();
hidePDialog();
}
private void hidePDialog() {
if (pDialog != null) {
pDialog.dismiss();
pDialog = null;
}
}
}