用數據更新ListView的正確方法？

我使用ParseQueryAdapter像這樣：用數據更新ListView的正確方法？

public class MyPostedSalesAdapter extends ParseQueryAdapter<Sale> { 

    static String mTAG = "LocalSalesAdapter"; 
    static ParseUser mCurrentUser = ParseUser.getCurrentUser(); 

    public MyPostedSalesAdapter(Context context) { 
     super(context, new ParseQueryAdapter.QueryFactory<Sale>() { 
      @SuppressWarnings("unchecked") 
      public ParseQuery<Sale> create() { 
       @SuppressWarnings("rawtypes") 
       ParseQuery query = new ParseQuery("Sales"); 
       query.orderByDescending("createdAt"); 
       query.whereEqualTo("postedBy", mCurrentUser.getUsername()); 
       try { 
        int salesAmount = query.count(); 
        ProfileActivity.setTextView(salesAmount); 
       } catch (ParseException e) { 

        e.printStackTrace(); 
       } 
       return query; 
      } 
     }); 
    } 

    @Override 
    public View getItemView(Sale sale, View v, ViewGroup parent) { 

     if (v == null) { 
      v = View.inflate(getContext(), R.layout.listview_cell, null); 
     } 

     super.getItemView(sale, v, parent); 

     ParseImageView saleImage = (ParseImageView) v.findViewById(R.id.icon); 
     ParseFile photoFile = sale.getParseFile("photo"); 
     if (photoFile != null) { 
      saleImage.setParseFile(photoFile); 
      saleImage.loadInBackground(new GetDataCallback() { 
       @Override 
       public void done(byte[] data, ParseException e) { 

       } 
      }); 
     } else { 
      // Clear ParseImageView if the object has no photo, set placeholder. 
      saleImage.setImageResource(R.drawable.placeholder); 
     } 
     TextView titleTextView = (TextView) v.findViewById(R.id.textView_listView_saleTitle); 
     titleTextView.setText(sale.getSaleTitle()); 

     TextView priceTextView = (TextView) v.findViewById(R.id.textView_listView_salePrice); 
     priceTextView.setText(sale.getSalePrice()); 
     return v; 
    } 

}

，簡單的onResume，設置適配器的ListView像這樣：

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

     mCurrentUser = ParseUser.getCurrentUser(); 

     // Setting up currentUser to current logged in user 
     // If user is not logged in, present them with Login Activity 
     if (mCurrentUser == null || !isUserOnline()) 
     { 
      presentUserWithLogin(); 

     } 
     else 
     { 
     mOwnSalesAdapter = new MyPostedSalesAdapter(this); 
    mOwnSalesAdapter.loadObjects(); 
    mUserSales.setAdapter(mOwnSalesAdapter); 
} 
}

我這樣做的onResume，想着每次活動被加載時，新數據被拖動使用查詢並顯示在ListView中。但事實並非如此，有時候會這樣。通常我必須關閉整個應用程序才能正確更新ListView並顯示數據的任何更新。即使如果我要註銷當前解析用戶，並在不關閉應用程序的情況下登錄另一個帳戶，以前的用戶帖子有時也會出現在列表視圖中。我究竟做錯了什麼？我在iOS上從未遇到過這樣的問題。還注意到如果我要從Parse中刪除一個Item並返回，通常該項目仍然出現在ListView中。

來源

2014-03-29 user3117785

嗨只是調用的onResume（）

if(mOwnSalesAdapter!=null) 
    mOwnSalesAdapter.notifyDataSetChanged();

來源

2014-03-29 16:56:40

用數據更新ListView的正確方法？

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