Dane ViewPager utracone po powrocie z następnego ekranu

Question

Używam ViewPager w mojej aplikacji i mam w nim trzy zakładki; Używam ViewPager wewnątrz fragmentu. Teraz mój problem polega na tym, że otrzymuję dane poprawnie podczas ładowania aplikacji, ale kiedy przejdę do następnej strony, a następnie z powrotem do ViewPagera, dane zostaną utracone, a karty nie będą działać. Proszę, pomóż mi. Poniżej jest mój kod:

import com.devpoint.rprtjobs.R; 

import android.support.v4.app.Fragment; 
import android.support.v4.app.FragmentTabHost; 
import android.support.v4.view.ViewPager; 
import android.support.v4.view.ViewPager.OnPageChangeListener; 
import android.support.v7.app.ActionBarActivity; 
import android.support.v7.widget.Toolbar; 
import android.os.Bundle; 
import android.view.LayoutInflater; 
import android.view.Menu; 
import android.view.MenuItem; 
import android.view.View; 
import android.view.ViewGroup; 
import android.support.design.widget.TabLayout; 


public class MainActivity extends Fragment { 

    // Declaring Your View and Variables 

    Toolbar toolbar; 
    ViewPager pager; 
    SwipeViewPagerAdapter adapter; 
    SlidingTabLayout tabs; 
    CharSequence Titles[]={"OnGoing","UpComing","Expired"}; 
    int Numboftabs =3; 
private View rootView; 

    @SuppressWarnings("deprecation") 
public View onCreateView(LayoutInflater inflater, ViewGroup container, 
      Bundle savedInstanceState) { 
     try { 
      rootView = inflater.inflate(R.layout.activity_main, 
        container, false); 


     adapter = new SwipeViewPagerAdapter(getActivity().getSupportFragmentManager(),Titles,Numboftabs); 

     // Assigning ViewPager View and setting the adapter 
     pager = (ViewPager) rootView.findViewById(R.id.pager); 
     pager.setAdapter(adapter); 

     // Assiging the Sliding Tab Layout View 
     tabs = (SlidingTabLayout) rootView.findViewById(R.id.tabs); 
     tabs.setDistributeEvenly(true); // To make the Tabs Fixed set this true, This makes the tabs Space Evenly in Available width 

     // Setting Custom Color for the Scroll bar indicator of the Tab View 
     tabs.setCustomTabColorizer(new SlidingTabLayout.TabColorizer() { 
      @Override 
      public int getIndicatorColor(int position) { 
       return getResources().getColor(R.color.tabsScrollColor); 
      } 
     }); 

     // Setting the ViewPager For the SlidingTabsLayout 
     tabs.setViewPager(pager); 

     pager.setOffscreenPageLimit(3); 

     pager.setOnPageChangeListener(new OnPageChangeListener() { 
      public void onPageScrollStateChanged(int state) {} 
      public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {} 

      public void onPageSelected(int position) { 

       if(position ==0) 
       { 
        SwipeViewPagerAdapter.Pagename = "ListOnGoing"; 
       } 
       else if(position ==1) 
       { 
        SwipeViewPagerAdapter.Pagename = "ListUpComing"; 
       } 
       else if(position ==2) 
       { 
        SwipeViewPagerAdapter.Pagename = "ListExpired"; 
       } 

       } 
     }); 


    } 
     catch(Exception e) 
     { 
      e.printStackTrace(); 
     } 
     return rootView; 

    } 

} 

Oto mój adapter:

import android.support.v4.app.Fragment; 
import android.support.v4.app.FragmentManager; 
import android.support.v4.app.FragmentPagerAdapter; 
import android.support.v4.app.FragmentStatePagerAdapter; 

/** 
* Created by Edwin on 15/02/2015. 
*/ 
public class SwipeViewPagerAdapter extends FragmentPagerAdapter { 

    CharSequence Titles[]; // This will Store the Titles of the Tabs which are Going to be passed when ViewPagerAdapter is created 
    int NumbOfTabs; // Store the number of tabs, this will also be passed when the ViewPagerAdapter is created 
    public static String Pagename="ListOnGoing"; 


    // Build a Constructor and assign the passed Values to appropriate values in the class 
    public SwipeViewPagerAdapter(FragmentManager fm,CharSequence mTitles[], int mNumbOfTabsumb) { 
     super(fm); 

     this.Titles = mTitles; 
     this.NumbOfTabs = mNumbOfTabsumb; 

    } 

    //This method return the fragment for the every position in the View Pager 
    @Override 
    public Fragment getItem(int position) { 

     switch (position) { 
     case 0: 
      //Pagename = "ListOnGoing"; 
      ListOnGoing mListOnGoing = new ListOnGoing(); 
      return mListOnGoing; 
     case 1: 
      //Pagename = "ListUpComing"; 
      ListUpComing mListUpComing = new ListUpComing(); 
      return mListUpComing; 
     case 2: 
      //Pagename = "ListExpired"; 
      ListExpaire mListExpaire = new ListExpaire(); 
      return mListExpaire; 
     default: 
      return null; 
    } 

    } 

    // This method return the titles for the Tabs in the Tab Strip 

    @Override 
    public CharSequence getPageTitle(int position) { 
     return Titles[position]; 
    } 

    // This method return the Number of tabs for the tabs Strip 

    @Override 
    public int getCount() { 
     return NumbOfTabs; 
    } 
} 

A oto jeden z moich kawałków:

import java.util.ArrayList; 
import java.util.HashMap; 
import java.util.List; 
import java.util.concurrent.CopyOnWriteArrayList; 

@SuppressLint("ShowToast") 
public class ListOnGoing extends Fragment implements OnItemClickListener { 
    Boolean isInternetPresent = false; 
    ConnectionDetector connectdetector; 
    public static ListView swipelisview; 
    Activity activity; 
    public static ProductListAdapter productListAdapter; 
    SharedPreference sharedPreference; 
    String LoggedIn; 
    boolean fragmentAlreadyLoaded = false; 


    @SuppressWarnings("deprecation") 
    @Override 
    public void onAttach(Activity activity) { 
     super.onAttach(activity); 
     this.listener = (FragmentActivity) activity; 
    } 


    @Override 
    public void onActivityCreated(Bundle savedInstanceState) { 
     super.onActivityCreated(savedInstanceState); 
    } 



    @Override 
    public void onViewCreated(View view, @Nullable Bundle savedInstanceState) { 

     try { 
      super.onViewCreated(view, savedInstanceState); 

      swipelisview = (ListView) rootView.findViewById(R.id.list); 

      View emptyView = rootView.findViewById(R.id.emptyView); 
      swipelisview.setEmptyView(emptyView); 

      if (savedInstanceState == null && !fragmentAlreadyLoaded) { 
       fragmentAlreadyLoaded = true; 
       repoObject = SplashScreen.getRepo(); 
       session = new SessionManager(getActivity()); 
       HashMap<String, String> Radious = session.getRadiousName(); 
       Radiosname = Radious.get(SessionManager.KEY_RadiousName); 
       //LoadActivity.Status=""; 
       GPlaces = new GetAllGooglePlaces(); 
       GPlaces.GetOpportunityList("", Radiosname, getActivity()); 
       DisPlayOppList(); 
      } 

      productListAdapter = new ProductListAdapter(getActivity(), 
        GetAllGooglePlaces.ArrayListOngoing); 
      swipelisview.setAdapter(productListAdapter); 
      productListAdapter.notifyDataSetChanged(); 


      session = new SessionManager(getActivity()); 
      HashMap<String, String> Radious = session.getRadiousName(); 
      Radiosname = Radious.get(SessionManager.KEY_RadiousName); 


      searchedit = (EditText) rootView.findViewById(R.id.searchbox); 

      Button searchbtn = (Button) rootView.findViewById(R.id.searchbtn); 


      searchedit = (EditText) rootView.findViewById(R.id.searchbox); 

      clearbtn = (Button) rootView.findViewById(R.id.clearbtn); 

      searchedit.addTextChangedListener(watch); 
      clearbtn.setOnClickListener(new View.OnClickListener() { 
      @Override 
      public void onClick(View arg0) { 
      LoadActivity.Status=""; 
      searchedit.setText(""); 
      GPlaces.GetOpportunityList("", Radiosname, getActivity()); 

      DisPlayOppList(); 
      } 
      }); 




      searchbtn.setOnClickListener(new View.OnClickListener() { 

       @Override 
       public void onClick(View arg0) { 

        getActivity().runOnUiThread(new Runnable() { 

         public void run() { 
          multipleCat = ""; 
          GetAllGooglePlaces.ArrayListOngoing = new CopyOnWriteArrayList<>(); 
          SearchText = searchedit.getText() 
            .toString(); 

          LoadActivity.Status = "Search"; 

          if (LoadActivity.isOnline) { 
           GPlaces.GetOpportunityList(SearchText, Radiosname, getActivity()); 

           DisPlayOppList(); 
          } 

          else { 
           List<OpportunityTable> alloffers = repoObject.roffertable 
             .getAlloffersbySearchKeyword(SearchText); 

           if (alloffers != null) { 

            GPlaces.FillArrayListOffline(alloffers,"OnGoing"); 
           } 

          } 

         } 
        }); 

       } 
      }); 



      HashMap<String, String> user = session.getLogin(); 
      LoggedIn = user.get(SessionManager.KEY_Login); 

      if (LoggedIn == null) { 
       LoggedIn = ""; 
      } 

      connectdetector = new ConnectionDetector(getActivity()); 



      try { 
       // Check if Internet present 
       isInternetPresent = connectdetector.isConnectingToInternet(); 

      } catch (Exception e) { 
       e.printStackTrace();    
       PostLogcatErrors ple = new PostLogcatErrors(); 
       ple.PostLogcatErorrs(e); 
      } 






      footerlayout = (LinearLayout) rootView.findViewById(R.id.footerlayout); 

      footerlayout.setOnTouchListener(new OnTouchListener() { 

       @Override 
       public boolean onTouch(View v, MotionEvent event) { 
        swipelisview.requestDisallowInterceptTouchEvent(true); 
        return true; 
       } 
      }); 





      swipelisview.setOnItemClickListener(new OnItemClickListener() { 
       public void onItemClick(AdapterView<?> arg0, View v, 
         final int position, long id) { 

        InputMethodManager imm = (InputMethodManager) getActivity() 
          .getSystemService(Context.INPUT_METHOD_SERVICE); 
        imm.hideSoftInputFromWindow(swipelisview.getWindowToken(), 0); 

        try { 
         final DetailsViewpagerFragment mDetailsViewpagerFragment = new DetailsViewpagerFragment(); 
         String url; 
         if (LoadActivity.isOnline) { 

          progresdialog = new ProgressDialog(getActivity()); 
          progresdialog.setMessage(Html 
            .fromHtml("<b>Search</b><br/>Loading Details...")); 
          progresdialog.setIndeterminate(false); 
          progresdialog.setCancelable(false); 
          progresdialog.show(); 

          ListDetails product = GetAllGooglePlaces.ArrayListOngoing 
            .get(position); 
          OpportunityID = product.getOfferID(); 


          url = LoadActivity.BaseUri + "SaveUserViewedOpportunities"; 

          JsonObjectRequest jsObjRequest; 
          jsObjRequest = new JsonObjectRequest(
            Request.Method.POST, url, 
            getSaveViewUserParams(), 
            new Response.Listener<JSONObject>() { 

             @Override 
             public void onResponse(JSONObject response) { 

              pagename = "Userplaceslist"; 

              mDetailsViewpagerFragment 
                .setClickList(position); 
              FragmentManager fragment = getFragmentManager(); 

              fragment.beginTransaction() 
                .replace(R.id.frame_container, 
                  mDetailsViewpagerFragment) 
                .commit(); 

              LoadActivity.CURRENTFRAGMENT = EnumModuleTags.SinglePlaceActivity; 



              ModuleFragmentBackStackingClass 
                .AddtoStack(
                  mDetailsViewpagerFragment, 
                  EnumModuleTags.SinglePlaceActivity, 
                  getString(R.string.mainfrgment_rprt)); 
              LoadActivity.updateActionbarMenu(); 

              progresdialog.dismiss(); 


             } 

            }, new Response.ErrorListener() { 

             @Override 
             public void onErrorResponse(
               VolleyError error) { 
              Toast.makeText(getActivity(), "False", 
                Toast.LENGTH_LONG).show(); 
              progresdialog.dismiss(); 
             } 
            }); 

          AppController.getInstance().addToRequestQueue(
            jsObjRequest); 
         } else { 

          mDetailsViewpagerFragment.setClickList(position); 
          FragmentManager fragment = getFragmentManager(); 

          fragment.beginTransaction() 
            .replace(R.id.frame_container, 
              mDetailsViewpagerFragment).commit(); 

          LoadActivity.CURRENTFRAGMENT = EnumModuleTags.SinglePlaceActivity; 
          ModuleFragmentBackStackingClass.AddtoStack(
            mDetailsViewpagerFragment, 
            EnumModuleTags.SinglePlaceActivity, 
            getString(R.string.mainfrgment_rprt)); 
         } 

        } catch (Exception e) { 
         e.printStackTrace();    
         PostLogcatErrors ple = new PostLogcatErrors(); 
         ple.PostLogcatErorrs(e); 
        } 

       } 

       private JSONObject getSaveViewUserParams() { 

        JSONObject params = new JSONObject(); 

        HashMap<String, String> UserId = session.getUserID(); 
        String UserIdVal = UserId.get(SessionManager.KEY_UserID); 



        if (!(UserIdVal == null)) { 
         UserIdVal = UserId.get(SessionManager.KEY_UserID); 
        } else { 
         UserIdVal = "0"; 
        } 

        try { 
         params.put("UserId", UserIdVal); 
         params.put("OpportunityID", OpportunityID); 
         params.put("UserViewedID", 0); 
         params.put("Shortlisted", true); 
         params.put("KeyValue", null); 
        } catch (JSONException e) { 
         e.printStackTrace();    
         PostLogcatErrors ple = new PostLogcatErrors(); 
         ple.PostLogcatErorrs(e); 
        } 

        return params; 
       } 

      }); 

      // Click The FavoritesItem on LongPress 
      swipelisview.setOnItemLongClickListener(new OnItemLongClickListener() { 

       @Override 
       public boolean onItemLongClick(AdapterView<?> parent, View view, 
         int position, long id) { 

        InputMethodManager imm; 
        imm = (InputMethodManager) getActivity() 
          .getSystemService(Context.INPUT_METHOD_SERVICE); 
        imm.hideSoftInputFromWindow(swipelisview.getWindowToken(), 0); 

        try { 
         ImageView button; 
         button = (ImageView) view 
           .findViewById(R.id.fav_checkbox); 

         String tag = button.getTag().toString(); 
         if (tag.equals(getString(R.string.grey_favcolor))) { 
          sharedPreference.addFavorite(activity, 
            GetAllGooglePlaces.ArrayListOngoing.get(position)); 
          button.setTag(getString(R.string.red_favcolor)); 
          button.setImageResource(R.drawable.checked); 
         } else if (tag.equals(getString(R.string.red_favcolor))){ 
          sharedPreference.removeFavorite(activity, 
            GetAllGooglePlaces.ArrayListOngoing.get(position)); 
          button.setTag(getString(R.string.grey_favcolor)); 
          button.setImageResource(R.drawable.unchecked); 
         } 

         return true; 
        } catch (NotFoundException e) { 
         e.printStackTrace();    
         PostLogcatErrors ple = new PostLogcatErrors(); 
         ple.PostLogcatErorrs(e); 
         Toast.makeText(getActivity(), e.getMessage(), 
           Toast.LENGTH_LONG).show(); 
         e.printStackTrace(); 
        } 
        return true; 
       } 

      }); 




      // Code placed here will be executed even when the fragment comes from 
      // backstack 
     } catch (Exception e) { 
      e.printStackTrace();    
      PostLogcatErrors ple = new PostLogcatErrors(); 
      ple.PostLogcatErorrs(e); 
     } 
    } 

    // String APIkey ="AIzaSyCAekTB0o1MuSYvUb-8HTZxhlJHE8yBUfI"; 
    @Override 
    public void onCreate(Bundle savedInstanceState) { 
     try { 
      super.onCreate(savedInstanceState); 
      activity = getActivity(); 
      sharedPreference = new SharedPreference(); 
      //setRetainInstance(true); 
     } catch (Exception e) { 
      e.printStackTrace();    
      PostLogcatErrors ple = new PostLogcatErrors(); 
      ple.PostLogcatErorrs(e); 
     } 
    } 

    @SuppressWarnings("static-access") 
    @SuppressLint({ "CutPasteId", "ClickableViewAccessibility" }) 
    @Override 
    public View onCreateView(LayoutInflater inflater, ViewGroup container, 
      Bundle savedInstanceState) { 
     try { 
      //setRetainInstance(true); 

      try 
      { 
       Tracker t = ((Analytics) getActivity().getApplication()).getTracker(
          TrackerName.APP_TRACKER); 

      t.setScreenName("UserPlaces Listview"); 

      t.send(new HitBuilders.AppViewBuilder().build()); 
      } 
      catch(Exception e) 
      { 
      Toast.makeText(getActivity().getApplication(), "Error"+e.getMessage(), 1).show(); 
      } 


      rootView = inflater.inflate(R.layout.user_places_listview, container, 
        false); 

      swipelisview = (ListView) rootView.findViewById(R.id.list); 

       View emptyView = rootView.findViewById(R.id.emptyView); 
       swipelisview.setEmptyView(emptyView); 


      return rootView; 
     } catch (Exception e) { 
      // TODO Auto-generated catch block 
      e.printStackTrace(); 
     } 
     return rootView; 
    } 


    TextWatcher watch = new TextWatcher(){ 

     @Override 
     public void afterTextChanged(Editable arg0) { 

     } 

     @Override 
     public void beforeTextChanged(CharSequence arg0, int arg1, int arg2, 
     int arg3) { 

     } 

     @Override 
     public void onTextChanged(CharSequence s, int a, int b, int c) { 

     if(c == 0){ 
     clearbtn.setVisibility(View.GONE); 
     } 
     else { 
     clearbtn.setVisibility(View.VISIBLE); 
     } 
     }}; 


    protected void LoadSearchPlaces(String searchparam) { 
     try { 
      if (LoadActivity.isOnline) { 

       JsonArrayRequest movieReq = new JsonArrayRequest("http://192.168.2.10/RPRT.WebApi/api/RPRT/" + "SearchPlaces/"+searchparam, 
         new Response.Listener<JSONArray>() { 
           @Override 
           public void onResponse(JSONArray response) { 
            List<HashMap<String, String>> aList = new ArrayList<>(); 
            for (int i = 0; i < response.length(); i++) { 
             JSONObject json_data; 
             try { 
              json_data = response.getJSONObject(i); 
              HashMap<String, String> hm = new HashMap<>(); 
              hm.put("Address", json_data.getString("Address")); 
              hm.put("City", json_data.getString("City")); 
              hm.put("Latitude", json_data.getString("Latitude")); 
              hm.put("Longitude", json_data.getString("Longitude")); 
              aList.add(hm); 
             } catch (JSONException e) { 
              // TODO Auto-generated catch block 
              e.printStackTrace(); 
             } 

            } 
            String[] from = { "Address"} ; 
            int[] to = { R.id.tv }; 
            SimpleAdapter adapterId = new SimpleAdapter(getActivity(), aList, 
              R.layout.user_places_dropdown_listitem, from, to); 

            //final AutoCompleteTextView autoCompView = (AutoCompleteTextView) rootView.findViewById(R.id.autoCompleteTextView); 

            autoCompView.setAdapter(adapterId); 

            autoCompView.setThreshold(1); 

            // Pname.setThreshold(1); 

            autoCompView.setOnItemClickListener(new AdapterView.OnItemClickListener() { 

             @SuppressWarnings("unchecked") 
             @Override 
             public void onItemClick(AdapterView<?> parent, View view, 
               int position, long id) { 
              HashMap<String, String> hm = (HashMap<String, String>) parent 
                .getAdapter().getItem(position); 

              autoCompView.setText(hm.get("Address")); 
              SplashScreen.nwLocation.setLatitude(Double.parseDouble(hm.get("Latitude"))); 
              SplashScreen.nwLocation.setLongitude(Double.parseDouble(hm.get("Longitude"))); 

              HashMap<String, String> Radious = session.getRadiousName(); 
               final String Radiosname; 
               Radiosname = Radious.get(SessionManager.KEY_RadiousName); 

               multipleCat=""; 
              ProgressDialog progresdialog = new ProgressDialog(getActivity()); 
              progresdialog.setMessage(Html 
                .fromHtml("<b>Search</b><br/>Loading Details...")); 
              progresdialog.setIndeterminate(false); 
              progresdialog.setCancelable(false); 
              //progresdialog.show(); 
              LoadActivity.Status=""; 
              GPlaces.GetOpportunityList(SearchText, Radiosname, getActivity()); 

              DisPlayOppList(); 

              searchdialog.cancel(); 


             } 

            }); 


          } 
         }, 
         new com.android.volley.Response.ErrorListener() { 
          @Override 
          public void onErrorResponse(
            VolleyError error) { 

          } 

         }); 

       AppController.getInstance().addToRequestQueue(movieReq); 


      } 

     } catch (Exception e) { 
      e.printStackTrace(); 
     } 
    } 




    private void DisPlayOppList() { 
     try { 

      pdialog = new ProgressDialog(getActivity()); 
      pdialog.setMessage(Html.fromHtml("<b>Search</b><br/>Loading Details...")); 
      pdialog.setIndeterminate(false); 
      pdialog.setCancelable(false); 


       if(LoadActivity.Status.equals("Slidemenulist")) 
       { 
        int CategoryId = 0; 
        switch (CopyOfListOnGoing.multipleCat) { 
         case "Books": 
          CategoryId = 1; 
          break; 
         case "BeautyandFashion": 
          CategoryId = 2; 
          break; 
         case "Electronic": 
          CategoryId = 3; 
          break; 
         case "Food": 
          CategoryId = 4; 
          break; 
         case "HomeService": 
          CategoryId = 5; 
          break; 
         case "Jobs": 
          CategoryId = 6; 
          break; 
         case "RealEstate": 
          CategoryId = 7; 
          break; 
         case "Vehicles": 
          CategoryId = 8; 
          break; 
        } 

        List<OpportunityTable> alloffers = repoObject.roffertable 
          .getAllCatOpp(CategoryId , Radiosname); 

        if (alloffers != null) { 

         GPlaces.FillArrayListOffline(alloffers,"OnGoing"); 
        } 

       } else { 
        List<OpportunityTable> alloffers = repoObject.roffertable 
          .getAlloffers(Integer.parseInt(Radiosname)); 

        if (alloffers != null) { 

         GPlaces.FillArrayListOffline(alloffers,"OnGoing"); 
        } 
       } 
     } 

     catch (Exception e) { 
      e.printStackTrace();    
      PostLogcatErrors ple = new PostLogcatErrors(); 
      ple.PostLogcatErorrs(e); 
     } 
    } 


    public void onItemClick(AdapterView<?> adapterView, View view, int position, long id) { 

     InputMethodManager imm = (InputMethodManager) getActivity().getSystemService(Context.INPUT_METHOD_SERVICE); 
     imm.hideSoftInputFromWindow(getActivity().getCurrentFocus().getWindowToken(), 0); 

     multipleCat = ""; 
     DisPlayOppList(); 

    } 


    /* @Override 
     public void onResume() { 
     Log.e("DEBUG", "onResume of Userplace ListView"); 
     super.onResume(); 
     }*/ 

     @Override 
     public void onPause() { 
     Log.e("DEBUG", "OnPause of Userplace ListView"); 
     super.onPause(); 
     } 




} 

a pozostałe fragmenty wyglądają tak samo. Proszę pomóż mi.

Answer 1

Po trochę reasearch Mam rozwiązanie dla mojego problemu, że po prostu nazywa getChildFragmentManager() zamiast getactivity(). GetSupportFragmentmanager(). To rozwiązać mój issue.Thanks StackOverflow

Answer 2

W rozszerzeniu adaptera FragmentStatePagerAdapter zamiast FragmentPagerAdapter rozwiąże on problem i jeśli korzystasz z ViewPager wewnątrz fragmentu, musisz użyć getChildFragmentManager() zamiast getActivity(). GetSupportFragmentManager(). daj mi znać, jeśli masz jakiś problem.

Nadzieja to pomaga :)

Answer 3

public float getPageWidth(int position) 
{ 
if (position == 0 || position == 2) 
{ 
return 0.8f; 
} 
return 1f; 
} 

Answer 4

pager = (ViewPager) rootView.findViewById(R.id.pager); 
pager.setOffscreenPageLimit(2);// no of fragments