Android ListView实现无限循环滚动
本文实例为大家分享了Android无限循环滚动的具体代码,供大家参考,具体内容如下
因项目需要循环展示列表数据,所以就实现了这个无限循环滚动的 LIstView.先说一下原理,原理呢,其实很简单,首先将要展示的数据循环展示三遍
监听ListView的滚动事件,当ListView滚动到第一遍第第二个时,ListView变自动跳到第二遍的第二个,同理,如果ListView滚动到倒数第一个时,ListView自动跳转到第二遍的倒数第一个,然后可以不停的向上或者向下滑动,永远不会到头,废话少说,上
代码:
让ListView循环三遍展示
首先利用取余的方法,将List里面的数据循环展示
public class ListAdapter extends BaseAdapter { private List<String> list; private LayoutInflater mInflater; public ListAdapter(Context context, List<String> list){ this.list = list; this.mInflater = LayoutInflater.from(context); } /** * 将数据循环展示三遍 */ @Override public int getCount() { if(list != null){ return list.size() * 3; } return 0; } @Override public Object getItem(int arg0) { return list.get(arg0 % list.size()); } @Override public long getItemId(int arg0) { return arg0 % list.size(); } @Override public View getView(int postition, View convertView, ViewGroup arg2) { ViewHoler viewHolder = null; if(convertView == null){ viewHolder = new ViewHoler(); convertView = mInflater.inflate(R.layout.adapter_list_layout, null); viewHolder.tvText = (TextView) convertView.findViewById(R.id.adapter_list_layout_tv); convertView.setTag(viewHolder); }else{ viewHolder = (ViewHoler) convertView.getTag(); } viewHolder.tvText.setText(list.get(postition % list.size()));//取余展示数据 return convertView; } static class ViewHoler{ TextView tvText; } }
然后实现监听ListView的滚动事件
public class MainActivity extends Activity implements OnScrollListener { private ListView listView; private List<String> list; private ListAdapter adapter; // private LinearLayout linear; // // private int stopPosition; // private int firstViewHeight; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); listView = (ListView) findViewById(R.id.listView1); list = getList(); adapter = new ListAdapter(this, list); listView.setAdapter(adapter); listView.setOnScrollListener(this); listView.setSelection(list.size()); } /** * 获取数据 * @return */ public List<String> getList(){ List<String> list = new ArrayList<String>(); for (int i = 0; i < 10; i++) { list.add(String.valueOf(i)); } return list; } @Override public void onScrollStateChanged(AbsListView view, int scrollState) { } /** * 设置滚动监听,当滚动到第二个时,跳到地list.size()+2个,滚动到倒数第二个时,跳到中间第二个,setSelection时, * 由于listView滚动并未停止,所以setSelection后会继续滚动,不会出现突然停止的现象 */ @Override public void onScroll(AbsListView view, int firstVisibleItem, int visibleItemCount, int totalItemCount) { /**到顶部添加数据关键代码*/ if (firstVisibleItem <= 2) { listView.setSelection(list.size() + 2); } else if (firstVisibleItem + visibleItemCount > adapter.getCount() - 2) {//到底部添加数据 listView.setSelection(firstVisibleItem - list.size()); } } }
就是这么简单,嘿嘿,表达能力有点欠缺,不知到你看懂没,没看懂的话,后面附上源码:Android无限循环滚动
以上就是本文的全部内容,希望对大家的学习有所帮助,也希望大家多多支持我们。
赞 (0)