Wie funktioniert die Seitennummerierung in Android?

Question

Wie man riesige Daten mit Paginierung anzeigen kann, habe ich mit Scroll-Ansicht versucht, aber ich denke, es ist nicht die richtige Art, so viel von Daten zu zeigen.

Answer 1

1. Endlose Scroll Klasse

public abstract class EndlessScrollListener implements AbsListView.OnScrollListener { 
    // The minimum amount of items to have below your current scroll position 
    // before loading more. 
    private int visibleThreshold =4; 
    // The current offset index of data you have loaded 
    private int currentPage = 0; 
    // The total number of items in the dataset after the last load 
    private int previousTotalItemCount = 0; 
    // True if we are still waiting for the last set of data to load. 
    private boolean loading = true; 
    // Sets the starting page index 
    private int startingPageIndex = 0; 

    public EndlessScrollListener() { 
    } 

    public EndlessScrollListener(int visibleThreshold) { 
     this.visibleThreshold = visibleThreshold; 
    } 

    public EndlessScrollListener(int visibleThreshold, int startPage) { 
     this.visibleThreshold = visibleThreshold; 
     this.startingPageIndex = startPage; 
     this.currentPage = startPage; 
    } 

    // This happens many times a second during a scroll, so be wary of the code you place here. 
    // We are given a few useful parameters to help us work out if we need to load some more data, 
    // but first we check if we are waiting for the previous load to finish. 
    @Override 
    public void onScroll(AbsListView view, int firstVisibleItem, int visibleItemCount, int totalItemCount) 
    { 
     // If the total item count is zero and the previous isn't, assume the 
     // list is invalidated and should be reset back to initial state 
//  System.out.println("totalItemCount test" +totalItemCount); 
//  System.out.println("previousTotalItemCount test" +previousTotalItemCount); 
//  System.out.println("loading test" +loading); 
//  System.out.println("currentPage test" +currentPage); 
     if (totalItemCount < previousTotalItemCount) { 
      this.currentPage = this.startingPageIndex; 
      this.previousTotalItemCount = totalItemCount; 
      if (totalItemCount == 0) { this.loading = true; } 
     } 
     // If it's still loading, we check to see if the dataset count has 
     // changed, if so we conclude it has finished loading and update the current page 
     // number and total item count. 
     if (loading && (totalItemCount > previousTotalItemCount)) { 
      loading = false; 
      previousTotalItemCount = totalItemCount; 
      currentPage++; 
     } 

     // If it isn't currently loading, we check to see if we have breached 
     // the visibleThreshold and need to reload more data. 
     // If we do need to reload some more data, we execute onLoadMore to fetch the data. 
     if (!loading && (totalItemCount - visibleItemCount) <= (firstVisibleItem + visibleThreshold)) { 
      loading = onLoadMore(currentPage, totalItemCount); 
     } 
    } 

    // Defines the process for actually loading more data based on page 
    // Returns true if more data is being loaded; returns false if there is no more data to load. 
    public abstract boolean onLoadMore(int page, int totalItemsCount); 

    @Override 
    public void onScrollStateChanged(AbsListView view, int scrollState) { 
     // Don't take any action on changed 
    } 
} 

2. Adapter Class

public class OpenJobAdapter extends BaseAdapter { 
     private Context context; 
     LayoutInflater inflater; 
     protected int serverListSize = -1; 
     public static final int VIEW_TYPE_LOADING = 0; 
     public static final int VIEW_TYPE_ACTIVITY = 1; 

     public OpenJobAdapter(Context context) { 
      this.context = context; 
     } 

     @Override 
     public int getCount() { 
      return mOpenJobList.size() + 1; 
     } 

     @Override 
     public int getViewTypeCount() { 
      return 2; 
     } 

     @Override 
     public int getItemViewType(int position) { 
      // TODO Auto-generated method stub 
      System.out.println("position :" + position); 
      System.out.println("mSpottedDishList.size() :" + mOpenJobList.size()); 
      return (position >= mOpenJobList.size()) ? VIEW_TYPE_LOADING 
        : VIEW_TYPE_ACTIVITY; 
     } 

     @Override 
     public Object getItem(int position) { 
      return (getItemViewType(position) == VIEW_TYPE_ACTIVITY) ? mOpenJobList 
        .get(position) : null; 
     } 

     @Override 
     public long getItemId(int position) { 
      return position; 
     } 

     @Override 
     public View getView(int position, View convertView, ViewGroup parent) { 
      if (getItemViewType(position) == VIEW_TYPE_LOADING) { 
       return getFooterView(position, convertView, parent); 
      } 
      View dataRow = convertView; 
      dataRow = getDataRow(position, convertView, parent); 

      return dataRow; 
     } 

     public View getFooterView(int position, View convertView, 
            ViewGroup parent) { 
      System.out.println("loading view :" + mLoadingFinished); 
      if (position >= serverListSize && mLoadingFinished) { 
       View view = new View(context); 
       return view; 
      } 

      View row = convertView; 
      if (row == null) { 
       inflater = (LayoutInflater) context 
         .getSystemService(Context.LAYOUT_INFLATER_SERVICE); 
       row = inflater.inflate(R.layout.list_footer, null); 
      } 

      return row; 
     } 

     public View getDataRow(final int position, View convertView, 
          ViewGroup parent) { 
      inflater = (LayoutInflater) context 
        .getSystemService(Context.LAYOUT_INFLATER_SERVICE); 
      final viewHold viewholder; 
      if (convertView == null) { 
       viewholder = new viewHold(); 
       inflater = (LayoutInflater) context 
         .getSystemService(Context.LAYOUT_INFLATER_SERVICE); 
       convertView = inflater.inflate(R.layout.openjobs_items, null); 
       viewholder.mCustomerName = (TextView) convertView 
         .findViewById(R.id.customername); 
       viewholder.mDateAndTime = (TextView) convertView 
         .findViewById(R.id.dateandtime); 
       viewholder.mCategoryName = (TextView) convertView 
         .findViewById(R.id.categoryname); 
       viewholder.mIssue = (TextView) convertView 
         .findViewById(R.id.issue); 
       viewholder.mRatings = (TextView) convertView 
         .findViewById(R.id.ratings); 
       convertView.setTag(viewholder); 
      } else { 
       viewholder = (viewHold) convertView.getTag(); 
      } 
      try { 
       viewholder.mCustomerName.setText(mOpenJobList.get(position).get(
         "serviceCategory")); 

      } catch (Exception e) { 
       // TODO: handle exception 
       e.printStackTrace(); 
      } 
      return convertView; 
     } 

     class viewHold { 
      public TextView mCustomerName, mDateAndTime, mCategoryName, mIssue, mRatings; 
     } 
    } 

3. Listview Scroll Zuhörer

mListOpenJob.setOnScrollListener(new EndlessScrollListener(0, 0) { 
       @Override 
       public boolean onLoadMore(int page, int totalItemsCount) { 
        if (Utils.isOnline(OpenJobsActivity.this)) { 
//Calling api 
         new OpenJobData().execute(page); 
        } else { 
         Utils.displayToast(OpenJobsActivity.this, getString(R.string.nonet)); 
        } 
        return true; 
       } 
      }); 

4.Calling Api und stellen Sie sicher, dass alle Seite beendet ist oder nicht boolean Flag verwendet

private boolean getopenjoblist(int skip) { 
     String url; 
     url = "Your url"; 
     try { 
      JSONObject json = new JSONObject(HttpUtil.apiGETResponseWithHeaders(url, getApplicationContext())); 
      if (json.getString("http_code").equals("400")) { 
       mLoadingFinished = true; 
      } 

      //do whatever here 
     } catch (Exception e) { 
     } 
     return true; 
    }