DButils的使用（增删改查）

要在Application中做整个全局的预加载应用：

public class TextUtil  extends Application{
public static DbUtils utils;

@Override
public void onCreate() {
// TODO Auto-generated method stub
super.onCreate();
utils = DbUtils.create(getApplicationContext());
}
}

import org.w3c.dom.Text;

import com.lidroid.xutils.DbUtils;
import com.lidroid.xutils.db.sqlite.DbModelSelector;
import com.lidroid.xutils.db.sqlite.Selector;
import com.lidroid.xutils.db.sqlite.WhereBuilder;
import com.lidroid.xutils.db.table.DbModel;
import com.lidroid.xutils.exception.DbException;

import android.app.Activity;
import android.os.Bundle;
import android.util.Log;
import android.view.Menu;
import android.view.MenuItem;

public class MainActivity extends Activity {
List<People> list_p = new ArrayList<People>();
private People p;

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);

try {
for (int i = 0; i < 4; i++) {

p = new People("王雪猪", 18);
// 保存方法
TextUtil.utils.save(p);
}

// 查看方法
list_p = TextUtil.utils.findAll(People.class);

/*
* 修改年龄
*/
People peo = list_p.get(1);
peo.setAge(110);
TextUtil.utils.update(peo, null);

/*
* 查看所有
*/
list_p = TextUtil.utils.findAll(People.class);
System.out.println(list_p);

/*
* 条件查询
*/
/*
* List<People>
* lp=TextUtil.utils.findAll(Selector.from(People.class)
* .where("id", "<=", "3") .and(WhereBuilder.b("id", ">=", "1")));
System.out.println(lp);
*/
/*
* 通过findfrist查找对象
*/
// People
// p=TextUtil.utils.findFirst(Selector.from(People.class).where("id",
// "=", "5"));
// System.out.println(p);

/*
* findDbModelAll查询
*/

/*
* List<DbModel> dbmodel=
* TextUtil.utils.findDbModelAll(DbModelSelector
* .from(People.class).where("id", "<", "4")); DbModel
* db=dbmodel.get(1);
*
* String name=db.getString("name"); int age=db.getInt("age");
* System.out.println(name+" ,"+age);
*/

/*
* 删除id=3的信息
*/

/*TextUtil.utils.deleteById(People.class, 3);
* list_p=TextUtil.utils.findAll(People.class);
*  Log.i("9b",list_p.toString());*/

/*删除集合下表为1的数据
*/

/*TextUtil.utils.delete(list_p.get(1));
list_p=TextUtil.utils.findAll(People.class);
Log.i("9b",list_p.toString());*/

/*
删除所有
*/
TextUtil.utils.deleteAll(People.class);
list_p=TextUtil.utils.findAll(People.class);
Log.i("9b",list_p.toString());

} catch (DbException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}

}