ListView中使用线程实现无限加载

footview的模版如下:     <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"       android:orientation="horizontal"         android:layout_width="fill_parent"         android:gravity="center_horizontal"         android:padding="3dp"         android:layout_height="fill_parent">               <TextView             android:id="@id/android:empty"             android:layout_width="wrap_content"             android:layout_height="fill_parent"             android:gravity="center"             android:padding="5dp"             android:text="Loading more days..."/>         </LinearLayout>  [代码] 然后记得在加到adapter前,把footview加到listview中去      View footerView = ((LayoutInflater)this.getSystemService(Context.LAYOUT_INFLATER_SERVICE)).inflate(R.layout.listfooter, null, false);             this.getListView().addFooterView(footerView);             this.setListAdapter(adapter);  [代码] listview的onscroll方法如下     this.getListView().setOnScrollListener(new OnScrollListener(){                                                       public void onScrollStateChanged(AbsListView view, int scrollState) {}                  public void onScroll(AbsListView view, int firstVisibleItem,                         int visibleItemCount, int totalItemCount) {                                                                               int lastInScreen = firstVisibleItem + visibleItemCount;                                   String last=Integer.toString(lastInScreen);                     Log.d("show",last);                     String total=Integer.toString(totalItemCount);                     Log.d("total",total);                                      if((lastInScreen == totalItemCount) && !(loadingMore)){                                           Thread thread =  new Thread(null, loadMoreListItems);                         thread.start();                     }                 }             });                                                Thread thread =  new Thread(null, loadMoreListItems);             thread.start();          /**    下面来分析下,其中,可以预先设置一个屏的listview能显示多少条记录,比如设置为5条,    这里itemsPerPage=15,然后首先    int lastInScreen = firstVisibleItem + visibleItemCount;      这里,获得每屏中最后一条数据的位置,比如一次先显示5条,则lastInScreen=5了,    */     if((lastInScreen == totalItemCount) && !(loadingMore)){     Thread thread =  new Thread(null, loadMoreListItems);             thread.start();     }     /**      这里是判断,如果是滚动了滚动条,并且用户以及功能浏览完了一次屏幕所需要的数目(比如5个),则启用线程序loadMoreListItems去处理,加载另外的新的5个了.    而如果没滚动,则第一次显示时,也要启用线程序loadMoreListItems去处理.    .      下面看loadMoreListItems.    */       private Runnable loadMoreListItems = new Runnable() {                                public void run() {                            loadingMore = true;                                            myListItems = new ArrayList<String>();                                  //Simulate a delay, delete this on a production environment!               try { Thread.sleep(1000);                } catch (InterruptedException e) {}                                  //Get 15 new listitems                 for (int i = 0; i < itemsPerPage; i++) {                                    myListItems.add("Date: " + (d.get(Calendar.MONTH)+ 1) + "/" + d.get(Calendar.DATE) + "/" + d.get(Calendar.YEAR) );                                          d.add(Calendar.DATE, 1);                                     }                                             runOnUiThread(returnRes);                              }        };            /**    在这个线程里,实际上就是用循环往listview中加日期,产生从当天时间起的若干个日期格式,然后调用 runOnUiThread(returnRes);去更新UI主线程,注意 runOnUiThread是    android提供的方法,可以帮助你在线程中执行UI更新操作.         在更新主线程中,十分简单,只不过往adapter中去增加元素,并且notifyDataSetChanged通知listview起变化了,    并设置loadingMore=false,因为已经加载完了一次了.    */
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