adapter的总结

BaseAdapter是一个抽象类，继承它需要实现较多的方法，所以也就具有较高的灵活性

ArrayAdapter支持泛型操作，最为简单，只能展示一行字

SimpleAdapter有最好的扩充性，可以自定义出各种效果

SimpleCursorAdapter可以适用于简单的纯文字型ListView，它需要Cursor的字段和UI的id对应起来。如需要实现更复杂的UI也可以重写其他方法。可以认为是SimpleAdapter对数据库的简单结合，可以方便地把数据库的内容以列表的形式展示出来。

ArrayAdapter

</pre><pre name="code" class="html">public class MyListView extends Activity {
    
        private ListView listView;
        //private List<String> data = new ArrayList<String>();
        @Override
        public void onCreate(Bundle savedInstanceState){
            super.onCreate(savedInstanceState);
             
            listView = new ListView(this);
            listView.setAdapter(new ArrayAdapter<String>(this, android.R.layout.simple_expandable_list_item_1,getData()));
            setContentView(listView);
        }
         
        private List<String> getData(){  
            List<String> data = new ArrayList<String>();
            data.add("a1");
            data.add("a2");
            data.add("a3");
            data.add("a4");       
            return data;
        }
    }

SimpleAdapter

<?xml version="1.0" encoding="utf-8"?>
    <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:orientation="horizontal" android:layout_width="fill_parent"
        android:layout_height="fill_parent">   
        <ImageView android:id="@+id/img" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_margin="5px"/>
        <LinearLayout android:orientation="vertical"  android:layout_width="wrap_content"  android:layout_height="wrap_content">
            <TextView android:id="@+id/title" android:layout_width="wrap_content" android:layout_height="wrap_content"
                android:textColor="#FFFFFFFF" android:textSize="22px" />
            <TextView android:id="@+id/info"  android:layout_width="wrap_content" android:layout_height="wrap_content"
                android:textColor="#FFFFFFFF" android:textSize="13px" />
        </LinearLayout>
     </LinearLayout>

public class SimpleAdapterActivity extends ListActivity {
     @Override
     public void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         
         SimpleAdapter adapter = new SimpleAdapter(this, getData(), R.layout.simple, new String[] { "title",  "img" }, new int[] { R.id.title, R.id.img });
         setListAdapter(adapter);
     }
     
     private List<Map<String, Object>> getData() {
         //map.put(参数名字,参数值)
         List<Map<String, Object>> list = new ArrayList<Map<String, Object>>();
         Map<String, Object> map = new HashMap<String, Object>();
         map.put("title", "摩托罗拉");
         map.put("img", R.drawable.icon);
         list.add(map);
         return list;
         }  
     
 }

SimpleCursorAdapter

public class SimpleCursorAdapterActivity extends ListActivity {
     @Override
     public void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         //获得一个指向系统通讯录数据库的Cursor对象获得数据来源
         Cursor cur = getContentResolver().query(People.CONTENT_URI, null, null, null, null);
         startManagingCursor(cur);
         //实例化列表适配器
         
         ListAdapter adapter = new SimpleCursorAdapter(this, android.R.layout.simple_list_item_1, cur, new String[] {People.NAME}, new int[] {android.R.id.text1});
         setListAdapter(adapter);
     }
 }

BaseAdapter

public class MyListView4 extends ListActivity {
    
    
    private List<Map<String, Object>> mData;
     
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        mData = getData();
        MyAdapter adapter = new MyAdapter(this);
        setListAdapter(adapter);
    }
 
    private List<Map<String, Object>> getData() {
        List<Map<String, Object>> list = new ArrayList<Map<String, Object>>();
 
        Map<String, Object> map = new HashMap<String, Object>();
        map.put("title", "G1");
        map.put("info", "google 1");
        map.put("img", R.drawable.i1);
        list.add(map);
 
        return list;
    }
    @Override
    protected void onListItemClick(ListView l, View v, int position, long id) {
         
        Log.v("MyListView4-click", (String)mData.get(position).get("title"));
    }
     
    public void showInfo(){
        new AlertDialog.Builder(this)
        .setTitle("我的listview")
        .setMessage("介绍...")
        .setPositiveButton("确定", new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int which) {
            }
        })
        .show();
         
    }
     
     
     
    public final class ViewHolder{
        public ImageView img;
        public TextView title;
        public TextView info;
        public Button viewBtn;
    }
     
     
    public class MyAdapter extends BaseAdapter{
 
        private LayoutInflater mInflater;
         
         
        public MyAdapter(Context context){
            this.mInflater = LayoutInflater.from(context);
        }
        @Override
        public int getCount() {
            return mData.size();
        }
 
        @Override
        public Object getItem(int arg0) {
            return null;
        }
 
        @Override
        public long getItemId(int arg0) {
            return 0;
        }
 
        @Override
        public View getView(int position, View convertView, ViewGroup parent) {
             
            ViewHolder holder = null;
            if (convertView == null) {
                 
                holder=new ViewHolder(); 
                 
                convertView = mInflater.inflate(R.layout.vlist2, null);
                holder.img = (ImageView)convertView.findViewById(R.id.img);
                holder.title = (TextView)convertView.findViewById(R.id.title);
                holder.info = (TextView)convertView.findViewById(R.id.info);
                holder.viewBtn = (Button)convertView.findViewById(R.id.view_btn);
                convertView.setTag(holder);
                 
            }else {
                 
                holder = (ViewHolder)convertView.getTag();
            }
             
             
            holder.img.setBackgroundResource((Integer)mData.get(position).get("img"));
            holder.title.setText((String)mData.get(position).get("title"));
            holder.info.setText((String)mData.get(position).get("info"));
             
            holder.viewBtn.setOnClickListener(new View.OnClickListener() {
                 
                @Override
                public void onClick(View v) {
                    showInfo();                
                }
            });
             
             
            return convertView;
        }
         
    }     
}