Firebase RecylcerView適配器不準確查看位置

Question

我正在使用Firebase用戶界面，並遇到一個獨特的問題。當我加載RecyclerView時，沒有問題。我單擊RecyclerView上的一個項目，並獲取被點擊的項目的.push（）值。然後，它會從存儲在Firebase數據庫中的該Firebase .push（）值中獲取數據，並將其發送到其他活動。見圖像下方：

第二圖像是經由意圖接收數據的活性。當我點擊回到RecyclerView時，我再次點擊「8」，然後我加載一個不同的數字（現在看起來是1）。

最終，我擔心我沒有正確設置RecyclerView。這裏是我的代碼：

創建民意調查對象（PO​​JO）和寫入火力地堡：

 mSubmitPollCreation.setOnClickListener(new View.OnClickListener() { 
     @Override 
     public void onClick(View v) { 

      //TODO: Need to check if poll requirements are added, i.e. Question, Answer, ...... 
      //check if image has been loaded first 
      if (resultImageURL == null) { 
       Toast.makeText(getApplicationContext(), getResources().getString(R.string.no_image_selected), Toast.LENGTH_LONG).show(); 
       return; 
      } 

      //capture answers 
      if (mNumberOfPollAnswersCreatedByUser > 5) { 
       Toast.makeText(getApplicationContext(), getResources().getText(R.string.poll_answers_greater_than_five), Toast.LENGTH_LONG).show(); 
       mNumberOfPollAnswersCreatedByUser = 5; 
      } 
      for (int i = 0; i < mNumberOfPollAnswersCreatedByUser; i++) { 
       EditText editText = (EditText) mEditTextAnswerLayout.findViewWithTag(getResources().getString(R.string.created_answer_editText_id) + String.valueOf(i + 1)); 
       String editTextInputForAnswer = String.valueOf(editText.getText()); 
       mPollAnswers.add(0, editTextInputForAnswer);     Toast.makeText(getApplicationContext(),editTextInputForAnswer,Toast.LENGTH_SHORT).show(); 
      } 


      Poll poll = new Poll(mCreatePollQuestion.getText().toString(), resultImageURL, mPollAnswers); 
      Map<String, Object> pollMap = poll.toMap(); 
      final String key = mBaseRef.child("Polls").push().getKey(); 
      Map<String, Object> childUpdates = new HashMap<String, Object>(); 
      childUpdates.put("/Polls/" + key, pollMap); 

      mBaseRef.updateChildren(childUpdates); 
      Collections.reverse(mPollAnswers); 
      for (int i = 0; i < mPollAnswers.size(); i++) { 
       mBaseRef.child("Polls").child(key).child("answers").child(String.valueOf(i + 1)).updateChildren(poll.answerConvert(mPollAnswers, i)); 
      } 

      Intent toHomeActivity = new Intent(CreateActivity.this, HomeActivity.class); 
      toHomeActivity.putExtra("viewpager_position", 2); 
      startActivity(toHomeActivity); 
     } 
    }); 

在哪裏，我從火力地堡閱讀並填充RecyclerView：

public class LiveFragment extends Fragment { 
// TODO: Rename parameter arguments, choose names that match 
// the fragment initialization parameters, e.g. ARG_ITEM_NUMBER 
private static final String ARG_PARAM1 = "param1"; 
private static final String ARG_PARAM2 = "param2"; 

private RecyclerView mRecyclerview; 
private DatabaseReference mBaseRef; 
private DatabaseReference mPollsRef; 
private LinearLayoutManager mLayoutManager; 
private FloatingActionButton mFloatingActionAdd; 

private FirebaseRecyclerAdapter<Poll, PollHolder> mFireAdapter; 

private RecyclerView.ItemAnimator mItemAnimator; 


// TODO: Rename and change types of parameters 
private String mParam1; 
private String mParam2; 

private OnFragmentInteractionListener mListener; 

public LiveFragment() { 
    // Required empty public constructor 
} 

/** 
* Use this factory method to create a new instance of 
* this fragment using the provided parameters. 
* 
* @param param1 Parameter 1. 
* @param param2 Parameter 2. 
* @return A new instance of fragment LiveFragment. 
*/ 
// TODO: Rename and change types and number of parameters 
public static LiveFragment newInstance(String param1, String param2) { 
    LiveFragment fragment = new LiveFragment(); 
    Bundle args = new Bundle(); 
    args.putString(ARG_PARAM1, param1); 
    args.putString(ARG_PARAM2, param2); 
    fragment.setArguments(args); 
    return fragment; 
} 

@Override 
public void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 
    mBaseRef = FirebaseDatabase.getInstance().getReference(); 
    mPollsRef = mBaseRef.child("Polls"); 

    if (getArguments() != null) { 
     mParam1 = getArguments().getString(ARG_PARAM1); 
     mParam2 = getArguments().getString(ARG_PARAM2); 

    } 
} 

@Override 
public View onCreateView(LayoutInflater inflater, ViewGroup container, 
         Bundle savedInstanceState) { 
    // Inflate the layout for this fragment 
    final View v = inflater.inflate(R.layout.fragment_new, container, false); 
    Log.v("TAG", "ON CREATE CALLED FROM NEW"); 

    mRecyclerview = (RecyclerView) v.findViewById(R.id.list); 
    mRecyclerview.setItemAnimator(new SlideInLeftAnimator()); 


    mLayoutManager = new LinearLayoutManager(getContext()); 
    mLayoutManager.setOrientation(LinearLayoutManager.VERTICAL); 
    mLayoutManager.setReverseLayout(true); 
    mLayoutManager.setStackFromEnd(true); 

    mFloatingActionAdd = (FloatingActionButton) getActivity().findViewById(R.id.myFAB); 
    mFloatingActionAdd.setOnClickListener(new View.OnClickListener() { 
     @Override 
     public void onClick(View v) { 
      Intent I = new Intent(getActivity().getApplicationContext(), CreateActivity.class); 
      startActivity(I); 
     } 
    }); 


    mRecyclerview.setLayoutManager(mLayoutManager); 
    return v; 
} 

// TODO: Rename method, update argument and hook method into UI event 
public void onButtonPressed(Uri uri) { 
    if (mListener != null) { 
     mListener.onFragmentInteraction(uri); 
    } 
    scrollToPosition(); 
} 

@Override 
public void onStart() { 
    super.onStart(); 

    mFireAdapter = new FirebaseRecyclerAdapter<Poll, PollHolder>(Poll.class, R.layout.latest_item, PollHolder.class, mBaseRef.child("Polls")) { 
     @Override 
     protected void populateViewHolder(PollHolder viewHolder, final Poll model, final int position) { 
      viewHolder.mPollQuestion.setText(model.getQuestion()); 
      Picasso.with(getActivity().getApplicationContext()) 
        .load(model.getImage_URL()) 
        .fit() 
        .into(viewHolder.mPollImage); 
      viewHolder.mView.setOnClickListener(new View.OnClickListener() { 
       @Override 
       public void onClick(View view) { 
        Log.v("TAG", model.toString()); 
        Log.v("TAG","ONCLICKED"); 
        Intent toPoll = new Intent(getActivity(), PollHostActivity.class); 
        toPoll.putExtra("POLL_ID", mFireAdapter.getRef(position).getKey()); 
        startActivity(toPoll); 

       } 
      }); 
      Log.v("TAG", mFireAdapter.getRef(position).getKey()); 
      Log.v("TAG", String.valueOf(position)); 
      Log.v("TAG", model.getQuestion()); 
      Log.v("TAG", model.getImage_URL()); 
     } 
    }; 

    mRecyclerview.setAdapter(mFireAdapter); 
    scrollToPosition(); 



} 

@Override 
public void onStop() { 
    super.onStop(); 
    if (mFireAdapter != null) { 
     mFireAdapter.cleanup(); 
    } 
} 


@Override 
public void onDetach() { 
    super.onDetach(); 
    mListener = null; 
} 


public static class PollHolder extends RecyclerView.ViewHolder implements View.OnClickListener { 

    TextView mPollQuestion; 
    ImageView mPollImage; 
    View mView; 


    public PollHolder(View itemView) { 
     super(itemView); 

     mPollQuestion = (TextView) itemView.findViewById(R.id.latest_item_question); 
     mPollImage = (ImageView) itemView.findViewById(R.id.pollThumbNailImage); 
     this.mView = itemView; 
     itemView.setOnClickListener(this); 

    } 

    @Override 
    public void onClick(View view) { 
     Log.v("TAG", "CLICKED"); 
    } 
} 


private void scrollToPosition(){ 
    mFireAdapter.registerAdapterDataObserver(new RecyclerView.AdapterDataObserver() { 
     @Override 
     public void onItemRangeInserted(int positionStart, int itemCount) { 
      super.onItemRangeInserted(positionStart, itemCount); 
      int pollCount = mFireAdapter.getItemCount(); 
      int lastVisiblePosition = mLayoutManager.findLastCompletelyVisibleItemPosition(); 

      // If the recycler view is initially being loaded or the user is at the bottom of the list, scroll 
      // to the bottom of the list to show the newly added message. 
      if (lastVisiblePosition == -1 || 
        (positionStart >= (pollCount - 1) && lastVisiblePosition == (positionStart - 1))) { 
       mRecyclerview.scrollToPosition(positionStart); 
      } 
     } 
    }); 
    } 
} 

我的想法：

1. 我在正確的位置打電話給mFireAdapter.cleanup（）？

2. 單擊「8」並看到「1」的問題沒有出現在RecyclerView的第一次加載中，它只發生在從活動（第二個圖像）返回並回到RecyclerView時。

3. 我調用.setStackFromEnd（true）和.setReverseLayout（true）來反轉存儲在FirebaseDatabase中的數據，這可能會導致問題。

4. 我設立在.populateViewHolder的.setOnClickListener（）（）方法，並使用以下中的意圖傳遞.push（）鍵到下一個活動：

   toPoll.putExtra("POLL_ID", mFireAdapter.getRef(position).getKey()); 
   

此方法可能會得到不正確的密鑰。

最後，火力地堡數據庫：

任何幫助，將不勝感激！

Answer 1

您不應該在populateViewHolder之外使用position，因爲它的值可能不同。相反，使您的viewHolder最終並使用viewHolder.getAdapterPosition()來取代它。