package com.example.basadper;import java.util.ArrayList;import java.util.HashMap;import java.util.Map;import android.os.Bundle;import android.app.Activity;import android.content.Context;import android.view.LayoutInflater;import android.view.Menu;import android.view.View;import android.view.ViewGroup;import android.widget.BaseAdapter;import android.widget.ImageView;import android.widget.ListView;import android.widget.TextView;public class MainActivity extends Activity {private ArrayList<Map<String,Object>>data;private ListView lV; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main);? ? ? ? lV = (ListView) findViewById(R.id.listView1);? ? ? ? MyAdaper adaper = new MyAdaper(this);? ? ? ? lV.setAdapter(adaper);? ? ? ?? }? public ArrayList<Map<String,Object>> getdata(){ ArrayList<Map<String,Object>> list = new ArrayList<Map<String,Object>>(); for(int i=0;i<=100;i++){ Map<String,Object> map1 = new HashMap<String,Object>(); map1.put("img", R.id.imageView1); map1.put("TextView", R.id.textView1); map1.put("TextView", R.id.textView2); list.add(map1); } return list;? } static class ViewHolder ? ? ?{ ? ? ? ? ?public ImageView img; ? ? ? ? ?public TextView title; ? ? ? ? ?public TextView info; ? ? ?} ??class MyAdaper extends BaseAdapter{ private LayoutInflater mInflater = null; ?? ? ?private MyAdaper(Context context) ?? ? ?{ ?? ? ? ? ?//根據(jù)context上下文加載布局，這里的是Demo17Activity本身，即this ?? ? ? ? ?this.mInflater = LayoutInflater.from(context); ?? ? ?} ? ? @Override public int getCount() { // TODO Auto-generated method stub return getdata().size(); } @Override public Object getItem(int position) { // TODO Auto-generated method stub return position; } @Override public long getItemId(int position) { // TODO Auto-generated method stub return position; } @Override public View getView(int position, View convertView, ViewGroup parent) { // TODO Auto-generated method stub ViewHolder holder = null; ?? ? ? ? //如果緩存convertView為空，則需要?jiǎng)?chuàng)建View ?? ? ? ? if(convertView == null) ?? ? ? ? { ?? ? ? ? ? ? holder = new ViewHolder(); ?? ? ? ? ? ? //根據(jù)自定義的Item布局加載布局 ?? ? ? ? ? ? convertView =?? ? ? ? ? ? holder.img = (ImageView)convertView.findViewById(R.id.imageView1); ?? ? ? ? ? ? holder.title = (TextView)convertView.findViewById(R.id.textView1); ?? ? ? ? ? ? holder.info = (TextView)convertView.findViewById(R.id.textView2); ?? ? ? ? ? ? //將設(shè)置好的布局保存到緩存中，并將其設(shè)置在Tag里，以便后面方便取出Tag ?? ? ? ? ? ? convertView.setTag(holder); ?? ? ? ? }else ?? ? ? ? { ?? ? ? ? ? ? holder = (ViewHolder)convertView.getTag(); ?? ? ? ? } ?? ? ? ? holder.img.setBackgroundResource((Integer)data.get(position).get("img")); ?? ? ? ? holder.title.setText((String)data.get(position).get("title")); ?? ? ? ? holder.info.setText((String)data.get(position).get("info")); ?? ? ? ? ??? ? ? ? return convertView; ?? ? } ? }?}