Android入门 ListView SimpleCursorAdapter实现

               

一般ListView都是用来显示列表的,一般列表的数据都是来自数据库的,因此我们这里假设前面已经实现了一个DBService类,里面存在pageCursorQuery(int offset,int length);

比如dbservice.pageCursorQuery(3,5);表示跳过3个记录,插入5条记录,返回Cursor;


pageCursorQuery实现代码如下,需要注意的是,查询语句的主键必须要重命名为“_id”,不然会报错。


public Cursor pageCursorQuery(int low,int high){ db = helper.getWritableDatabase(); Cursor cursor = db.query("person", new String[]{"id as _id","name","age"}, null, null, null, null, null,low+","+high); return cursor;}

MainActivity.java


package org.xiazdong.db;import org.xiazdong.db.service.DBService;import android.app.Activity;import android.database.Cursor;import android.os.Bundle;import android.widget.ListView;import android.widget.SimpleCursorAdapter;public class MainActivity extends Activity private ListView listView; @Override    public void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.main);        listView = (ListView)this.findViewById(R.id.listview);        DBService service = new DBService(this);        Cursor cursor = service.pageCursorQuery(0, 10);        SimpleCursorAdapter adapter = new SimpleCursorAdapter(this, R.layout.item,cursor, new String[]{"_id","name","age"}, new int[]{R.id.id1,R.id.name,R.id.age});        listView.setAdapter(adapter); }}

总结:SimpleCursorAdapter和SimpleAdapter最大的区别就是

(1)前者是用Cursor表示数据,后者用List<Map<String,Object>>表示数据;

(2)前者的查询语句的主键必须要为"_id";

           

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转载自blog.csdn.net/dtijcfrhb/article/details/86561240