求大神~~AsyncTask数据被重复了~~~~

[rekym]

代码如下,其中ASP网页上执行存储过程查询SQL数据,查询指定页,每页只显示50条,所以ListView滚动到底部时只加载50条数据

	class PageTask extends AsyncTask<String, Integer, String> {

		// 可变长的输入参数，与AsyncTask.exucute()对应
		@Override
		protected String doInBackground(String... params) {

			try {
                                //加载URL网页数据params[0]=URL地址
				HttpPost httpRequest = new HttpPost(params[0]);
				/*
				 * NameValuePair实现请求参数的封装
				 */
				try {
					/* 添加请求参数到请求对象 */
					httpRequest.setEntity(new UrlEncodedFormEntity(param,
							HTTP.UTF_8));
					/* 发送请求并等待响应 */
					HttpClient httpClient = new DefaultHttpClient();
					httpClient.getParams().setParameter(
							CoreConnectionPNames.CONNECTION_TIMEOUT,
							R.string.read_time);
					httpClient.getParams()
							.setParameter(CoreConnectionPNames.SO_TIMEOUT,
									R.string.read_time);
					/* 发送请求并等待响应 */
					HttpResponse httpResponse = httpClient.execute(httpRequest);
					/* 若状态码为200 ok */
					if (httpResponse.getStatusLine().getStatusCode() == 200) {
						/* 读返回数据 */
						StringBuffer sb = new StringBuffer();
						HttpEntity entity = httpResponse.getEntity();
						long length = entity.getContentLength();
						InputStream is = entity.getContent();
						BufferedReader br = new BufferedReader(
								new InputStreamReader(is, "UTF-8"));
						String data = "";
						int count = 0;
						Log.v("lengthcount", Long.toString(length));

						while ((data = br.readLine()) != null) {
							sb.append(data);
							count = sb.length();
							if (length > 0) {
								// 如果知道响应的长度，调用publishProgress（）更新进度
								publishProgress((int) ((count / (float) length) * 100));
								Log.v("pb", Long.toString(count));
							}
							// 为了在模拟器中清楚地看到进度，让线程休眠100ms
							// Thread.sleep(100);
						}
						return (sb == null ? "" : sb.toString());
					} else {
						return "";
					}
				} catch (ClientProtocolException e) {
					e.printStackTrace();
				} catch (IOException e) {
					e.printStackTrace();
				} catch (Exception e) {
					e.printStackTrace();
				}

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

		@Override
		protected void onCancelled() {
			super.onCancelled();
		}

		@Override
		protected void onPostExecute(String result) {
			// 返回HTML页面的内容
			// message.setText(result);
			orderListData = "";
			if (result != "") {
				Log.v("aaaaa", result);
				if (result.indexOf("</HEAD>") > 1) {
					orderListData = result.substring(
							result.indexOf("</HEAD>") + 7).trim();
				}
				orderList.setTag(String.valueOf((Integer.parseInt(orderList
						.getTag().toString()) + 1)));

				// 添加数据至ListView
				AddList();
			}
			pbar.setProgress(0);
			pbar.setVisibility(View.GONE);
			headertext.setVisibility(View.VISIBLE);
		}

		@Override
		protected void onPreExecute() {
			// 任务启动，可以在这里显示一个对话框，这里简单处理
			// message.setText(R.string.task_started);
		}

		@Override
		protected void onProgressUpdate(Integer... values) {
			pbar.setProgress(values[0]);
		}

		protected void AddList() {
			String[] countries = orderListData.split("<br>");
                        //然后这里就有问题了,LOG输出countries.length是100条记录,实际应该只是50条,查看加载完后的数据后面50条重复了,但是在doInBackground只执行了一次,LOG.V输出信息也只有一 次
			Log.v("RowS", "" + countries.length); 
			for (int i = 0; i < countries.length; i++) {
				orderDetails = countries[i].split(",");

				if (orderDetails.length == 12) {
					HashMap<String, Object> user = new HashMap<String, Object>();
					user.put("img", R.drawable.user);
					user.put("orderno", orderDetails[0]);
					user.put("customername", orderDetails[1]);
					user.put("orderdate", orderDetails[2]);
					user.put("productname", orderDetails[3]);
					user.put("totalnum", "  " + orderDetails[4]);
					user.put("outnum", orderDetails[5]);
					user.put("areas", orderDetails[6]);
					user.put("outareas", orderDetails[7]);
					user.put("amount", orderDetails[8] + ".0");
					user.put("outmoney", orderDetails[9] + ".0");
					user.put("paymoney", orderDetails[10] + ".0");
					user.put("examine", orderDetails[11]);
					Log.v("add", "" + i);
					users.add(user);
				} else {
					Toast.makeText(Order_Info.this, "数组游标错误.",
							Toast.LENGTH_LONG).show();
				}
			}

			orderListData = "";

                        //还有这个是不是有问题呀,我更新完ListView后,只要手机屏幕一旋转,所有的后面的数据都丢失,只有原来的数据
			saImageItems.notifyDataSetChanged();
			((TextView) findViewById(R.id.order_totalrow)).setText((orderList
					.getCount() - 1) + " 行");
		}
	}

[rekym]

while ((data = br.readLine()) != null) {
sb.append(data);
count = sb.length();
if (length > 0) {
// 如果知道响应的长度，调用publishProgress（）更新进度
publishProgress((int) ((count / (float) length) * 100));
Log.v("pb", Long.toString(count));
}
// 为了在模拟器中清楚地看到进度，让线程休眠100ms
// Thread.sleep(100);
}
return (sb == null ? "" : sb.toString());

顶上，，这里数据会重复掉，原来50行，现在是100行。。。