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Android:如何檢測所有ListView對象都已加載

[英]Android: How to detect that all ListView objects are loaded

差不多一個星期,我想知道如何檢測所有ListView對象(行)的加載方式(不成功)。 我的ListView是Load-More類型(我已經將限制設置為5行,所以在每5行之后它會加載更多5行)。 我正在使用Parse.com框架。 加載整個列表后,我想刪除頁腳視圖。 有關詳情,請參閱下面的代碼。

你有任何想法或建議,如何完成它?

提前致謝。

public class Fragment1 extends Fragment {
    private ListView mListView;
    private AnimalAdapter mAdapter;
    ProgressBar mProgressBar;
    EditText mEditText;
    RelativeLayout mRelativeLayout;
    ProgressBar oProgressBar;
    LinearLayout mLinearLayout;
    Context context;
    LayoutInflater inflater;

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
            Bundle savedInstanceState) {

        final View rootView = inflater.inflate(R.layout.animalsfrag, container, false);
        mListView = (ListView)rootView.findViewById(R.id.animal_list);

        View header = getActivity().getLayoutInflater().inflate(R.layout.header, null);
        header.setPadding(2, 8, 4, 2);


        mListView.setVisibility(View.INVISIBLE);
        mListView.requestFocus();
        mListView.addHeaderView(header);
        View footer = getActivity().getLayoutInflater().inflate(R.layout.footer, null);
        mListView.addFooterView(footer);
        footer.setVisibility(View.VISIBLE);


        mProgressBar = (ProgressBar) rootView.findViewById (R.id.loading_animals);
        mProgressBar.setVisibility(View.VISIBLE);

        RemoteDataTask task = new RemoteDataTask();
        task.execute();





    return rootView;
    }





     public void updateData() { //Main area no.1
         mListView = (ListView)getView().findViewById(R.id.animal_list);
         int limit = mListView.getCount() + 5;
         ParseQuery<Animal> query = ParseQuery.getQuery(Animal.class);


      query.setCachePolicy(CachePolicy.CACHE_THEN_NETWORK);
    query.orderByAscending("animal");
    query.setLimit(limit);

       Toast.makeText(getActivity(), "now", Toast.LENGTH_SHORT).show();



    query.findInBackground(new FindCallback<Animal>() {


        @Override
          public void done(List<Animal> animals, ParseException error) {

              if(animals != null){
                  mAdapter.clear();

               mProgressBar.setVisibility(View.INVISIBLE);
              for (int i = 0; i < animals.size(); i++) {

                      mAdapter.add(animals.get(i));



                  }


              }



          }


      });

    }

     private class RemoteDataTask extends AsyncTask<Void, Void, Void> {




         @Override
            protected void onPreExecute() {
                super.onPreExecute();






            }


         @Override
            protected Void doInBackground(Void... params) {


                    updateData();




                return null;
            }


         @Override
            protected void onPostExecute(Void result) {

               mListView = (ListView) getView().findViewById(R.id.animal_list);
                // Pass the results into ListViewAdapter.java
               mAdapter = new AnimalAdapter(getActivity(), new ArrayList<Animal>());
               mListView.setAdapter(mAdapter);




               mListView.setVisibility(View.VISIBLE);
               mListView.setTextFilterEnabled(true);



                mListView.setAdapter(mAdapter);
                mAdapter = new AnimalAdapter(getActivity(), new ArrayList<Animal>());
                mListView = (ListView) getView().findViewById(R.id.animal_list);
                mAdapter = new AnimalAdapter(getActivity(), new ArrayList<Animal>());
                mListView.setAdapter(mAdapter);


                 mListView.setAdapter(mAdapter);
                mEditText = (EditText) getView().findViewById(R.id.search_animal);

                mListView.setOnScrollListener(new OnScrollListener() {



                    @Override //Main area no.2
                    public void onScroll(AbsListView view, int firstVisibleItem, int visibleItemCount,
                            int totalItemCount) {
                         final int lastItem = firstVisibleItem + visibleItemCount;



                           if(lastItem == totalItemCount) {
                                updateData();



                           }



                        mListView.setFooterDividersEnabled(false);
                    }

                    @Override
                    public void onScrollStateChanged(AbsListView view,
                            int scrollState) {
                        if (SCROLL_STATE_TOUCH_SCROLL == scrollState) {
                            View currentFocus = getActivity().getCurrentFocus();
                            if(currentFocus != null) {
                                currentFocus.clearFocus();
                            }

                            mEditText = (EditText) getActivity().findViewById(R.id.search_animal);
                            InputMethodManager imm = (InputMethodManager)getActivity().getSystemService(
                                      Context.INPUT_METHOD_SERVICE);
                                imm.hideSoftInputFromWindow(mEditText.getWindowToken(), 0);




                            }

                    }

                });

                mEditText.addTextChangedListener(new TextWatcher(){

                    @Override
                    public void afterTextChanged(Editable s) {


                    }

                    @Override
                    public void beforeTextChanged(CharSequence s,
                            int start, int count, int after) {


                    }

                    @Override
                    public void onTextChanged(CharSequence s, int start,
                            int before, int count) {

                        System.out.println("Text ["+s+"]");
                        mAdapter.getFilter().filter(s.toString());



                    }
                });


                  }

         }


}

首先,您應該檢查項目的總數

例如:20項

然后最初setLimit = 5並且在你的“Loadmore”異步任務中,你應該跳過像“setSkip”這樣的先前值。所以它不會加載前5個項目並查詢接下來的5個項目

這樣,您可以檢查最后一個塊是否已加載,一旦加載了20個項目,請刪除頁腳。

我希望這有幫助。

您可以查看此鏈接並使用listvieew中的滾動:onScrollListener的實現,以檢測ListView中滾動的結束

並在滾動的結束動作中刪除您的頁腳..

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