Android（三）数据存储之三SQLite嵌入式数据库 3

在mail.xml所在目录里添加一个contactitem.xml：

<?xml version="1.0" encoding="utf-8"?>

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"

         android:layout_width="wrap_content" android:layout_height="wrap_content">

 

         <!-- contact.id -->

         <TextView android:layout_width="30dip" android:layout_height="wrap_content"

                   android:textSize="20sp" android:id="@+id/tv_id" />

 

         <!-- contact.name -->

         <TextView android:layout_width="150dip" android:layout_height="wrap_content"

                   android:textSize="20sp" android:layout_toRightOf="@id/tv_id"

                   android:layout_alignTop="@id/tv_id" android:id="@+id/tv_name" />

 

         <!-- contact.phone -->

         <TextView android:layout_width="150dip" android:layout_height="wrap_content"

                   android:textSize="20sp" android:layout_toRightOf="@id/tv_name"

                   android:layout_alignTop="@id/tv_name" android:id="@+id/tv_phone" />

 

</RelativeLayout>

 

 

       编辑AndroidSQLite类：

package com.changcheng.sqlite;

 

import java.util.ArrayList;

import java.util.HashMap;

import java.util.List;

import com.changcheng.sqlite.R;

import com.changcheng.sqlite.entity.Contact;

import com.changcheng.sqlite.service.ContactsService;

import android.app.Activity;

import android.database.Cursor;

import android.os.Bundle;

import android.view.View;

import android.widget.AdapterView;

import android.widget.ListView;

import android.widget.SimpleAdapter;

import android.widget.Toast;

import android.widget.AdapterView.OnItemClickListener;

 

public class AndroidSQLite extends Activity {

         /** Called when the activity is first created. */

         @Override

         public void onCreate(Bundle savedInstanceState) {

                   super.onCreate(savedInstanceState);

                   setContentView(R.layout.main);

                   // 获取分页数据

                   ContactsService contactsService = new ContactsService(this);

                   List<Contact> contacts = contactsService.getScrollData(0, 3);

                   // 获取ListView

                   ListView lv = (ListView) this.findViewById(R.id.listView);

                   // 生成List<? extends Map<String, ?>>数据

                   List<HashMap<String, Object>> data = new ArrayList<HashMap<String, Object>>();

                   for (Contact contact : contacts) {

                            HashMap<String, Object> item = new HashMap<String, Object>();

                            item.put("_id", contact.get_id());

                            item.put("name", contact.getName());

                            item.put("phone", contact.getPhone());

                            data.add(item);

                   }

                   // 生成Adapter

                   SimpleAdapter adapter = new SimpleAdapter(this, data,

                                     R.layout.contactitem, new String[] { "_id", "name", "phone" },

                                     new int[] { R.id.tv_id, R.id.tv_name, R.id.tv_phone });

                   // 设置ListView适配器

                   lv.setAdapter(adapter);

                  

                   // 为ListView添加事件

                   lv.setOnItemClickListener(new OnItemClickListener() {

 

                            @Override

                            public void onItemClick(AdapterView<?> parent, View view,

                                               int position, long id) {

                                     HashMap<String, Object> item = (HashMap<String, Object>) parent

                                                        .getItemAtPosition((int) id);

                                     Toast.makeText(AndroidSQLite.this, item.get("name").toString(),

                                                        1).show();

                            }

 

                   });

         }

}

 

上面编写的分页显示数据比较麻烦，Android为我们提供了一个SimpleCursorAdapter类。使用它可以方便的显示分页数据。将AndroidSQLite类修改为：

      

package com.changcheng.sqlite;

 

import com.changcheng.sqlite.R;

import com.changcheng.sqlite.service.ContactsService;

import android.app.Activity;

import android.database.Cursor;

import android.os.Bundle;

import android.widget.ListView;

import android.widget.SimpleCursorAdapter;

 

public class AndroidSQLite extends Activity {

         /** Called when the activity is first created. */

         @Override

         public void onCreate(Bundle savedInstanceState) {

                   super.onCreate(savedInstanceState);

                   setContentView(R.layout.main);

 

                   // 获取分页数据

                   ContactsService contactsService = new ContactsService(this);

                   Cursor cursor = contactsService.getScrollDataCursor(0, 3);

                   // 获取ListView

                   ListView lv = (ListView) this.findViewById(R.id.listView);

                   // 创建Adapter

                   SimpleCursorAdapter adapter = new SimpleCursorAdapter(this,

                                     R.layout.contactitem, cursor, new String[] { "_id", "name",

                                                        "phone" }, new int[] { R.id.tv_id, R.id.tv_name,

                                                        R.id.tv_phone });

                   // 设置ListView适配器

                   lv.setAdapter(adapter);

 

                   // 为ListView添加事件

                   lv.setOnItemClickListener(new OnItemClickListener() {

 

                            @Override

                            public void onItemClick(AdapterView<?> parent, View view,

                                               int position, long id) {

                                     Cursor cursor = (Cursor) parent

                                                        .getItemAtPosition((int) position);

                                     Toast.makeText(AndroidSQLite.this, cursor.getString(1), 1)

                                                        .show();

                            }

                   });

         }

}

 

       OK，在Android中的SQLite操作总结结束！