分组 布局 adapter

package com.example.listview;import java.util.ArrayList;import java.util.HashMap;import android.app.ListActivity;import android.content.Context;import android.graphics.Color;import android.os.Bundle;import android.view.LayoutInflater;import android.view.View;import android.view.ViewGroup;import android.widget.BaseAdapter;import android.widget.ListView;import android.widget.TextView;public class MainActivity extends ListActivity {//item view的类型总数private final int VIEW_TYPE_COUNT = 2;private final String DATA="data";private final String TYPE="type";private final int GROUP=-2;private final int ITEM=-3;private ArrayList<HashMap<String,Object>> items = null;@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);ListView listview = this.getListView();BaseAdapter adapter = new MyBaseAdapter();items = new ArrayList<HashMap<String, Object>>(); listview.setAdapter(adapter);String [] groups={"A","B","C","D","E","F"};int count=0;for(int i=0;i<groups.length;i++){HashMap<String,Object> group_map = new HashMap<String,Object>();group_map.put(TYPE,GROUP);group_map.put(DATA, groups[i]);items.add(group_map);for (int j = 0; j < 5; j++) {                  HashMap<String, Object> data_map = new HashMap<String, Object>();                  data_map.put(TYPE, ITEM);                  data_map.put(DATA, "数据:" + (count++));                  items.add(data_map);              }  }}private class MyBaseAdapter extends BaseAdapter{private LayoutInflater inflater = null;public  MyBaseAdapter(){inflater = (LayoutInflater) getSystemService(Context.LAYOUT_INFLATER_SERVICE);}@Overridepublic int getCount() {return items.size();}@Overridepublic Object getItem(int position) {HashMap<String, Object> map = items.get(position);return map.get(DATA); }@Overridepublic long getItemId(int position) {return position;}@Overridepublic View getView(int position, View convertView, ViewGroup parent) {int type = getItemViewType(position);//根据不同的view type加载不同的布局文件 switch(type){case GROUP:convertView = inflater.inflate(android.R.layout.simple_list_item_2,null);TextView tv1 = (TextView) convertView.findViewById(android.R.id.text1);tv1.setText("分组");tv1.setBackgroundColor(Color.RED);TextView tv2 = (TextView) convertView.findViewById(android.R.id.text2);                           tv2.setText(getItem(position) + "");                  tv2.setBackgroundColor(Color.GRAY);                 break;case ITEM:convertView = inflater.inflate(                          android.R.layout.simple_list_item_1, null);                  TextView tv = (TextView) convertView                          .findViewById(android.R.id.text1);                  tv.setText(getItem(position) + "");                  break;  }return convertView;}//解析view type//view type值是我们事先埋入到items数据中的字段值//注意：此处的返回值不要大于getViewTypeCount（）的返回值@Overridepublic int getItemViewType(int position) {HashMap<String, Object> map = items.get(position);return (Integer) map.get(TYPE);}// 在本例中共计有2个不同类型的view          // android.R.layout.simple_list_item_1 和          // android.R.layout.simple_list_item_1.@Overridepublic int getViewTypeCount() {return VIEW_TYPE_COUNT;  }}}