android ListView列表显示数据

<?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">

<TextView
android:layout_width="120dp"
android:textSize="22sp"
android:layout_height="wrap_content"
android:id="@+id/name"
/>

<TextView
android:layout_width="150dp"
android:textSize="22sp"
android:layout_height="wrap_content"
android:id="@+id/phone"
/>

<TextView
android:layout_width="fill_parent"
android:textSize="22sp"
android:layout_height="wrap_content"
android:id="@+id/amount"
/>
</LinearLayout>

public class MainActivity extends Activity {
private ListView listView;
private PersonService personService;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
personService = new PersonService(this);

listView = (ListView) this.findViewById(R.id.listView);
listView.setOnItemClickListener(new ItemClickListener());
show2();
}

private final class ItemClickListener implements OnItemClickListener{
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
ListView lView = (ListView)parent;
/* 自定义适配器
Person person = (Person) lView.getItemAtPosition(position);
Toast.makeText(getApplicationContext(), person.getId().toString(), 1).show();*/

Cursor cursor = (Cursor) lView.getItemAtPosition(position);
int personid = cursor.getInt(cursor.getColumnIndex("_id"));
Toast.makeText(getApplicationContext(), personid+ "", 1).show();
}
}

//自定义适配器

private void show3() {
List<Person> persons = personService.getScrollData(0, 20);
PersonAdapter adapter = new PersonAdapter(this, persons, R.layout.item);
listView.setAdapter(adapter);
}

private void show2() {
//此适配器要求有一个字段为_id，不然会报错，解决方法两种，1、增加_id的字段 2、为字段指定别名
Cursor cursor = personService.getCursorScrollData(0, 20);
SimpleCursorAdapter adapter = new SimpleCursorAdapter(this, R.layout.item, cursor,
new String[]{"name", "phone", "amount"}, new int[]{R.id.name, R.id.phone, R.id.amount});
listView.setAdapter(adapter);
}

private void show() {
List<Person> persons = personService.getScrollData(0, 20);
List<HashMap<String, Object>> data = new ArrayList<HashMap<String,Object>>();
for(Person person : persons){
HashMap<String, Object> item = new HashMap<String, Object>();
item.put("name", person.getName());
item.put("phone", person.getPhone());
item.put("amount", person.getAmount());
item.put("id", person.getId());
data.add(item);
}
SimpleAdapter adapter = new SimpleAdapter(this, data, R.layout.item,
new String[]{"name", "phone", "amount"}, new int[]{R.id.name, R.id.phone, R.id.amount});

listView.setAdapter(adapter);

}
}

public class PersonAdapter extends BaseAdapter {
private List<Person> persons;//在绑定的数据
private int resource;//绑定的条目界面，item.xml
private LayoutInflater inflater; //布局填充器，通过上下文得到

public PersonAdapter(Context context, List<Person> persons, int resource) {
this.persons = persons;
this.resource = resource;
inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
}

@Override

public int getCount() {
return persons.size();//数据总数
}

@Override
public Object getItem(int position) {
return persons.get(position);
}

@Override
public long getItemId(int position) {
return position;
}

@Override
public View getView(int position, View convertView, ViewGroup parent) {
TextView nameView = null;
TextView phoneView = null;
TextView amountView = null;
//利用View的缓存
if(convertView==null){
convertView = inflater.inflate(resource, null);//生成条目界面对象
nameView = (TextView) convertView.findViewById(R.id.name);
phoneView = (TextView) convertView.findViewById(R.id.phone);
amountView = (TextView) convertView.findViewById(R.id.amount);

ViewCache cache = new ViewCache();
cache.nameView = nameView;
cache.phoneView = phoneView;
cache.amountView = amountView;
convertView.setTag(cache);
}else{
ViewCache cache = (ViewCache) convertView.getTag();
nameView = cache.nameView;
phoneView = cache.phoneView;
amountView = cache.amountView;
}
Person person = persons.get(position);
//下面代码实现数据绑定
nameView.setText(person.getName());
phoneView.setText(person.getPhone());
amountView.setText(person.getAmount().toString());

return convertView;
}

private final class ViewCache{
public TextView nameView;
public TextView phoneView;
public TextView amountView;
}

}