Android ListView加载更多

先看效果：

ListView的footer布局：

<?xml version="1.0" encoding="utf-8"?>

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"

    android:layout_width="fill_parent"

    android:layout_height="wrap_content"

    android:paddingBottom="10dp"

    android:paddingTop="10dp" >

<TextView

        android:id="@+id/pulldown_footer_text"

        android:layout_width="wrap_content"

        android:layout_height="wrap_content"

        android:layout_centerInParent="true"

        android:text="加载更多日志"

        android:textSize="15dp" />
<ProgressBar

        android:id="@+id/pulldown_footer_loading"

        style="@android:style/Widget.ProgressBar.Small.Inverse"

        android:layout_width="wrap_content"

        android:layout_height="wrap_content"

        android:layout_centerVertical="true"

        android:layout_marginLeft="20dp"/>
</RelativeLayout>

ListView的item和main_activity布局很简单，分别是一个TextView和ListView,不再贴出。

MainActivity代码贴出：

import java.util.ArrayList;

import java.util.List;

import android.app.Activity;

import android.os.Bundle;

import android.view.LayoutInflater;

import android.view.View;

import android.view.ViewGroup;

import android.widget.AbsListView.OnScrollListener;

import android.widget.AbsListView;

import android.widget.BaseAdapter;

import android.widget.ListView;

import android.widget.RelativeLayout;

import android.widget.TextView;

import android.widget.Toast;
public class MainActivity extends Activity

{

	private ListView listview;

	private LayoutInflater inflater;

	private List<String> arrays = new ArrayList<String>();

	private RelativeLayout footer;

	private MyAdapter adapter;

	// 每页显示条数

	private Integer perpage = 20;

	// 当前页数

	private Integer currentpage = 1;

	// 最大页数

	private Integer maxpage = 1;
@Override

	public void onCreate(Bundle savedInstanceState)

	{

		super.onCreate(savedInstanceState);

		setContentView(R.layout.activity_main);
setMaxPage(40);

		loadData(currentpage, perpage);
inflater = getLayoutInflater();

		listview = (ListView) this.findViewById(R.id.pulldownview);

		footer = (RelativeLayout) View.inflate(getApplicationContext(), R.layout.pulldown_footer, null);

		listview.addFooterView(footer, null, true);

		adapter = new MyAdapter();

		listview.setAdapter(adapter);

		listview.setOnScrollListener(new OnScrollListener()

		{
@Override

			public void onScrollStateChanged(AbsListView view, int scrollState)

			{

				if (view.getLastVisiblePosition() == view.getCount() - 1)

				{

					if (currentpage != maxpage)

					{

						currentpage++;

						loadData(currentpage, perpage);

						adapter.notifyDataSetChanged();

					} else

					{

						Toast.makeText(getApplicationContext(), "没有更多的数据！", Toast.LENGTH_SHORT).show();

						listview.removeFooterView(footer);

					}

				}

			}
@Override

			public void onScroll(AbsListView view, int firstVisibleItem, int visibleItemCount, int totalItemCount)

			{
}

		});

	}
/**

	 * 模拟分页查询数据

	 *

	 * @param currentpage当前页数

	 * @param perpage

	 *            每页显示数

	 */

	private void loadData(Integer currentpage, Integer perpage)

	{

		// 起始数据

		Integer firstResult = (currentpage - 1) * perpage;

		// 获取的最大数据

		Integer maxResult = currentpage * perpage;

		System.out.println("firstResult:"+firstResult+"  "+"maxResult:"+maxResult);

		// select * from database where XXXX order by XX limit firstResult,maxResult //order by可省略，但有order by时limit必需在它后面

		for (; firstResult < maxResult; firstResult++)

		{

			arrays.add("这是测试数据" + (firstResult+1));

		}

	}
/**

	 * 模拟获取最大页数

	 *

	 * @param total

	 *            总的数据

	 */

	private void setMaxPage(Integer total)

	{

		if (total % perpage == 0)

		{

			maxpage = total / perpage;

		} else

		{

			maxpage = total / perpage + 1;

		}

		System.out.println("maxpage:"+maxpage);

	}
private class MyAdapter extends BaseAdapter

	{
@Override

		public int getCount()

		{

			return arrays == null ? 0 : arrays.size();

		}
@Override

		public Object getItem(int position)

		{

			return null;

		}
@Override

		public long getItemId(int position)

		{

			return 0;

		}
@Override

		public View getView(int position, View convertView, ViewGroup parent)

		{

			ViewHolder holder;

			if (convertView == null)

			{

				holder = new ViewHolder();

				convertView = inflater.inflate(R.layout.item_list, null);

				holder.textView = (TextView) convertView.findViewById(R.id.text);

				convertView.setTag(holder);

			} else

			{

				holder = (ViewHolder) convertView.getTag();

			}

			holder.textView.setText(arrays.get(position));

			return convertView;

		}

	}
private static class ViewHolder

	{

		TextView textView;

	}

}

Android ListView加载更多,码迷,mamicode.com