Android之怎么使用SQLite数据库(增、删、改、查、分页等)以及ListView显示数据

由于刚接触android开发，故此想把学到的基础知识记录一下，以备查询，故此写的比较啰嗦：

步骤如下：

一、介绍：

此文主要是介绍怎么使用android自带的数据库SQLite，以及把后台的数据用ListView控件显示

二、新建一个android工程——DBSQLiteOperate

工程目录：

Android之怎么使用SQLite数据库(增、删、改、查、分页等)以及ListView显示数据

三、清单列表AndroidManifest.xml的配置为：

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.dboperate"
    android:versionCode="1"
    android:versionName="1.0" >

<uses-sdk android:minSdkVersion="8" />

</manifest>

四、main.xml配置清单：

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical" >
    <LinearLayout android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:orientation="horizontal" >

</LinearLayout>
    <ListView
        android:id="@+id/listView"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent" >
    </ListView>

</LinearLayout>

五、item.xml配置清单：

</LinearLayout>

六、string.xml配置清单：

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

    <string name="hello">Hello World, DBSQLiteOperateActivity!</string>
    <string name="app_name">ExampleDBSQLiteOperate8</string>
    <string name="name">姓名</string>
    <string name="phone">电话</string>
    <string name="amount">存款</string>

</resources>

七、DBSQLiteOperateActivity.java Activity类的源码：

package com.example.dboperate;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import com.example.adapter.PersonAdapter;
import com.example.domain.Person;
import com.example.service.PersonService;

import android.app.Activity;
import android.database.Cursor;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.ListView;
import android.widget.SimpleAdapter;
import android.widget.SimpleCursorAdapter;
import android.widget.Toast;

public class DBSQLiteOperateActivity extends Activity {

ListView listView;
PersonService personService;
OnItemClickListener listViewListener;
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        listViewListener = new OnItemClickListener(){

   @Override
   public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
    //得到listView控件
    ListView listView = (ListView)parent;

    //1、如果使用自定义适配器，返回的是Person对象
    //得到该条目数据
//    Person person = (Person)listView.getItemAtPosition(position);
//    //广播出去
//    Toast.makeText(getApplicationContext(), person.toString(), Toast.LENGTH_LONG).show();

    //2、如果使用showList2()方法中的适配器时，则取得的值是不一样的,返回的是cursor
//    Cursor cursor = (Cursor)listView.getItemAtPosition(position);
//    int personid = cursor.getInt(cursor.getColumnIndex("_id"));
//    Toast.makeText(getApplicationContext(), personid+"", Toast.LENGTH_LONG).show();

    //3、如果使用showList()方法中的适配器时，则取得的值是不一样的,返回的是map
    @SuppressWarnings("unchecked")
    Map<String,Object> map = (Map)listView.getItemAtPosition(position);
    String name = map.get("name").toString();
    String personid = map.get("personid").toString();
    Toast.makeText(getApplicationContext(), personid +"-"+ name, Toast.LENGTH_LONG).show();

   }

        };

        listView = (ListView) this.findViewById(R.id.listView);
        listView.setOnItemClickListener(listViewListener);
        personService = new PersonService(this);
        showList();
    }
private void showList() {
  List<Person> persons = personService.getScrollData(0, 50);
  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("personid", 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 void showList2(){
  Cursor cursor = personService.getCursorScrollData(0, 50);
  //该适配器要求返回的结果集cursor必须包含_id字段，所以需要对取得结果集进行处理
  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);
}
/**
* 自定义适配器
*/
public void showList3(){
  List<Person> persons = personService.getScrollData(0, 50);
  /**
   * 第一个参数：上下文context，第二个参数：要显示的数据，第三个参数：绑定的条目界面
   */
  PersonAdapter adapter = new PersonAdapter(this, persons, R.layout.item);
  listView.setAdapter(adapter);
}
}

八、person.java 实体类源码：

package com.example.domain;

public class Person {

private Integer id;
private String name;
private String phone;
private Integer amount;
public Integer getId() {
  return id;
}
public void setId(Integer id) {
  this.id = id;
}
public String getName() {
  return name;
}
public void setName(String name) {
  this.name = name;
}
public String getPhone() {
  return phone;
}
public void setPhone(String phone) {
  this.phone = phone;
}

public Person(String name, String phone) {
  this.name = name;
  this.phone = phone;
}
public Person(Integer id, String name, String phone,Integer amount) {
  super();
  this.id = id;
  this.name = name;
  this.phone = phone;
  this.amount = amount;
}
public Person() {
  super();
}
public Integer getAmount() {
  return amount;
}
public void setAmount(Integer amount) {
  this.amount = amount;
}
@Override
public String toString() {
  return "Person [id=" + id + ", name=" + name + ", phone=" + phone
    + ", amount=" + amount + "]";
}

}

九、DBOperateHelper.java 业务类源码：

package com.example.service;

import android.content.Context;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteDatabase.CursorFactory;
import android.database.sqlite.SQLiteOpenHelper;

public class DBOperateHelper extends SQLiteOpenHelper {

public DBOperateHelper(Context context) {//默认创建的数据库文件保存在<包名>/database/
//第一个参数是上下文，第二个参数是数据库名称，第三个是游标工厂为null时使用数据库默认的游标工厂,第四个是数据库版本号但是不能为0，一般大于0
super(context, "smallpig", null, 4);
}

/**
* 数据库每一次被创建时被调用
*/
@Override
public void onCreate(SQLiteDatabase sqldb) {
  sqldb.execSQL("create table person(personid integer primary key autoincrement,name varchar(20),phone varchar(12) null)");

}
    /**
     * 每一次数据库版本号发生变动时触发此方法
     * 比如如果想往数据库中再插入一些表、字段或者其他信息时通过修改数据库版本号来触发此方法
     */
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
  //db.execSQL("alter table person add phone varchar(12) null");\
  db.execSQL("alter table person add amount Integer null");
}

}

十、PersonService.java 业务类源码：

package com.example.service;

import java.util.ArrayList;
import java.util.List;

import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;

import com.example.domain.Person;

public class PersonService {

private DBOperateHelper dbOperateHelper;

public PersonService(Context context) {
  this.dbOperateHelper = new DBOperateHelper(context);
}
    /**
     * 保存记录
     * @param person
     */
public void save(Person person){
  //得到数据库实例，里面封装了数据库操作方法
  SQLiteDatabase sqldb = dbOperateHelper.getWritableDatabase();
     //sqldb.execSQL("insert into person(name,phone) values('"+person.getName()+"','"+person.getPhone()+"')");
  //利用占位符可以避免注入，但是注意数组参与与占位符对应的字段要一一对应
  sqldb.execSQL("insert into person(name,phone,amount) values(?,?,?)",new Object[]{person.getName(),person.getPhone(),person.getAmount()});
     //关闭数据库
  sqldb.close();
}

/**
* 删除记录
* @param id
*/
public void delete(Integer id){
  SQLiteDatabase sqldb = dbOperateHelper.getWritableDatabase();
  sqldb.execSQL("delete from person where personid=?",new Object[]{id});
  sqldb.close();
}

/**
* 更新记录
* @param person
*/
public void update(Person person){
  SQLiteDatabase sqldb = dbOperateHelper.getWritableDatabase();
  sqldb.execSQL("update person set name=?,phone=?,amount=? where personid=?",new Object[]{person.getName(),person.getPhone(),person.getAmount(),person.getId()});
  sqldb.close();
}

/**
* 通过ID查询记录
* @param id
* @return
*/
public Person find(Integer id){
  /**
   * getWritableDatabase 与 getReadableDatabase 的区别：
   * getReadableDatabase会先返回getWritableDatabase(可写)，如果调用getWritableDatabase失败
   * 则才会调用getReadableDatabase后续方法，使数据库只读
   * 当写入的数据超过数据库大小则调用getWritableDatabase会失败
   * 所以只读时则可以使用此方法，其它情况(只要不是超过数据库大小)也可以使用此方法
   */
  SQLiteDatabase sqldb = dbOperateHelper.getReadableDatabase();
  Cursor cursor = sqldb.rawQuery("select * from person where personid=?", new String[]{String.valueOf(id)});
  int personid;
  String name;
  String phone;
  int amount;
  Person person = null;
  if(cursor.moveToFirst()){
   personid = cursor.getInt(cursor.getColumnIndex("personid"));
   name = cursor.getString(cursor.getColumnIndex("name"));
   phone = cursor.getString(cursor.getColumnIndex("phone"));
   amount = cursor.getInt(cursor.getColumnIndex("amount"));
   person = new Person(personid,name,phone,amount);
  }
  cursor.close();
  return person;
}

/**
* 返回指定长度记录，limit 3,5,适用于分页
* @param offset 起始
* @param maxResult 长度
* @return
*/
public List<Person> getScrollData(int offset,int maxResult){

  SQLiteDatabase sqldb = dbOperateHelper.getReadableDatabase();
  Cursor cursor = sqldb.rawQuery("select * from person order by personid asc limit ?,?", new String[]{String.valueOf(offset),String.valueOf(maxResult)});
  int personid;
  String name;
  String phone;
  int amount;
  Person person = null;
  List<Person> persons = new ArrayList<Person>();
  while(cursor.moveToNext()){
   personid = cursor.getInt(cursor.getColumnIndex("personid"));
   name = cursor.getString(cursor.getColumnIndex("name"));
   phone = cursor.getString(cursor.getColumnIndex("phone"));
   amount = cursor.getInt(cursor.getColumnIndex("amount"));
   person = new Person(personid,name,phone,amount);
   persons.add(person);
  }
  cursor.close();
  return persons;
}

/**
* 返回cursor
* @param offset 起始
* @param maxResult 长度
* @return
*/
public Cursor getCursorScrollData(int offset,int maxResult){

  SQLiteDatabase sqldb = dbOperateHelper.getReadableDatabase();
  Cursor cursor = sqldb.rawQuery("select personid as _id,name,phone,amount from person order by personid asc limit ?,?", new String[]{String.valueOf(offset),String.valueOf(maxResult)});

  return cursor;
}

/**
* 返回总记录数
* @return
*/
public long getCount(){
  SQLiteDatabase sqldb = dbOperateHelper.getReadableDatabase();

  Cursor cursor = sqldb.rawQuery("select count(*) from person", null);
  //该查询语句值返回一条语句
  cursor.moveToFirst();
  long result = cursor.getLong(0);
  cursor.close();
  return result;
}

public void payment(){
  SQLiteDatabase sqldb = dbOperateHelper.getWritableDatabase();
  sqldb.beginTransaction();//开启事务
  try{
   sqldb.execSQL("update person set amount = amount -10 where personid=1");
   sqldb.execSQL("update person set amount = amount + 10 where personid=2");
   sqldb.setTransactionSuccessful();//设置事务标志位true
  } finally {
   //结束事务：有两种情况：commit\rollback，事务提交或者回滚是由事务的标识决定的
   //事务为ture则提交，事务为flase则回滚，默认为false
   sqldb.endTransaction();
  }
}
}

十一、OtherPersonService.java 业务类源码：

package com.example.service;

import java.util.ArrayList;
import java.util.List;

import com.example.domain.Person;

import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteDatabase.CursorFactory;
import android.database.sqlite.SQLiteOpenHelper;

public class OtherPersonService {

private DBOperateHelper dbOperateHelper;

public OtherPersonService(Context context) {
  this.dbOperateHelper = new DBOperateHelper(context);
}
    /**
     * 保存记录
     * @param person
     */
public void save(Person person){
  //得到数据库实例，里面封装了数据库操作方法
  SQLiteDatabase sqldb = dbOperateHelper.getWritableDatabase();
     //sqldb.execSQL("insert into person(name,phone) values('"+person.getName()+"','"+person.getPhone()+"')");
  //利用占位符可以避免注入，但是注意数组参与与占位符对应的字段要一一对应
  //sqldb.execSQL("insert into person(name,phone) values(?,?)",new Object[]{person.getName(),person.getPhone()});

  ContentValues values = new ContentValues();
  values.put("name", person.getName());
  values.put("phone", person.getPhone());
  values.put("amount", person.getAmount());
  //第一个参数是表名，第三个为字段值集合，第二个参数是空值字段，当第三个字段值集合为空时，系统会自动插入一条第二个参数为空的sql语句
  //否则当第三个参数为空时，如果第二个参数也为空，那么插入表就会找不到插入的字段信息，会报错
  sqldb.insert("person", "name", values );
  //关闭数据库
  sqldb.close();
}

/**
* 删除记录
* @param id
*/
public void delete(Integer id){
  SQLiteDatabase sqldb = dbOperateHelper.getWritableDatabase();
  //sqldb.execSQL("delete from person where personid=?",new Object[]{id});
  //第一个参数是表名，第二个是where后面的条件用占位符表示，第三个对应占位符为参数值
  sqldb.delete("person", "personid=?", new String[]{Integer.toString(id)});
  sqldb.close();
}

/**
* 更新记录
* @param person
*/
public void update(Person person){
  SQLiteDatabase sqldb = dbOperateHelper.getWritableDatabase();
  //sqldb.execSQL("update person set name=?,phone=? where personid=?",new Object[]{person.getName(),person.getPhone(),person.getId()});
  //第一个参数为表名，第二个是一个更新值集合，采用键值对的形式，每个更新的字段对应更新值
  //第三个参数是where后面条件字段用占位符标识，第四个参数是对应where占位符的值
  ContentValues values = new ContentValues();
  values.put("name", person.getName());
  values.put("phone", person.getPhone());
  values.put("amount", person.getAmount());
  sqldb.update("person", values , "personid=?", new String[]{person.getId().toString()});
  sqldb.close();
}

/**
* 通过ID查询记录
* @param id
* @return
*/
public Person find(Integer id){
  /**
   * getWritableDatabase 与 getReadableDatabase 的区别：
   * getReadableDatabase会先返回getWritableDatabase(可写)，如果调用getWritableDatabase失败
   * 则才会调用getReadableDatabase后续方法，使数据库只读
   * 当写入的数据超过数据库大小则调用getWritableDatabase会失败
   * 所以只读时则可以使用此方法，其它情况(只要不是超过数据库大小)也可以使用此方法
   */
  SQLiteDatabase sqldb = dbOperateHelper.getReadableDatabase();
  //Cursor cursor = sqldb.rawQuery("select * from person where personid=?", new String[]{String.valueOf(id)});
  //第一个参数是表名；第二个参数是查询显示的字段，null时默认查询显示所有字段；
  //第三个参数是where查询条件占位符；第四个是占位符对应的值；
  //第五个参数是group by条件；第六个是having条件；第七个是order by条件
  Cursor cursor = sqldb.query("person", null, "personid=?", new String[]{id.toString()}, null, null, null);
  int personid;
  String name;
  String phone;
  int amount;
  Person person = null;
  if(cursor.moveToFirst()){
   personid = cursor.getInt(cursor.getColumnIndex("personid"));
   name = cursor.getString(cursor.getColumnIndex("name"));
   phone = cursor.getString(cursor.getColumnIndex("phone"));
   amount = cursor.getInt(cursor.getColumnIndex("amount"));
   person = new Person(personid,name,phone,amount);
  }
  cursor.close();
  return person;
}

/**
* 返回指定长度记录，limit 3,5,适用于分页
* @param offset 起始
* @param maxResult 长度
* @return
*/
public List<Person> getScrollData(int offset,int maxResult){

  SQLiteDatabase sqldb = dbOperateHelper.getReadableDatabase();
  //Cursor cursor = sqldb.rawQuery("select * from person order by personid asc limit ?,?", new String[]{String.valueOf(offset),String.valueOf(maxResult)});
  //第一个参数是表名；第二个参数是查询显示的字段，null时默认查询显示所有字段；
  //第三个参数是where查询条件占位符；第四个是占位符对应的值；
  //第五个参数是group by条件；第六个是having条件；第七个是order by条件
  //第八个参数是limit ?,? 条件
  Cursor cursor = sqldb.query("person", null, null, null, null, null, "personid",offset+","+maxResult);

  int personid;
  String name;
  String phone;
  int amount;
  Person person = null;
  List<Person> persons = new ArrayList<Person>();
  while(cursor.moveToNext()){
   personid = cursor.getInt(cursor.getColumnIndex("personid"));
   name = cursor.getString(cursor.getColumnIndex("name"));
   phone = cursor.getString(cursor.getColumnIndex("phone"));
   amount = cursor.getInt(cursor.getColumnIndex("amount"));
   person = new Person(personid,name,phone,amount);
   persons.add(person);
  }
  cursor.close();
  return persons;
}

/**
* 返回总记录数
* @return
*/
public long getCount(){
  SQLiteDatabase sqldb = dbOperateHelper.getReadableDatabase();
  //Cursor cursor = sqldb.rawQuery("select count(*) from person", null);
  //第一个参数是表名；第二个参数是查询显示的字段，null时默认查询显示所有字段；
  //第三个参数是where查询条件占位符；第四个是占位符对应的值；
  //第五个参数是group by条件；第六个是having条件；第七个是order by条件
  Cursor cursor = sqldb.query("person", new String[]{"count(*)"}, null, null, null, null, null);
  //该查询语句值返回一条语句
  cursor.moveToFirst();
  long result = cursor.getLong(0);
  cursor.close();
  return result;
}

}

十二、PersonServiceTest.java 单元测试类源码：

package com.example.test;

import java.util.List;

import com.example.domain.Person;
import com.example.service.DBOperateHelper;
import com.example.service.PersonService;import android.test.AndroidTestCase;
import android.util.Log;

public class PersonServiceTest extends AndroidTestCase {

public void testCreateDB() throws Exception{
  DBOperateHelper dbHelper = new DBOperateHelper(getContext());
  dbHelper.getWritableDatabase();
}
public void testSave() throws Exception{
  PersonService ps = new PersonService(getContext());
  for(int i=1;i<=100;i++){
   Person person = new Person();
   person.setName("我是"+i);
   person.setPhone(String.valueOf(Long.parseLong("18888888800")+i));
   ps.save(person);
   Log.i("PersonService",person.toString());
  }
}
public void testDelete() throws Exception{
  PersonService ps = new PersonService(getContext());
  ps.delete(10);
}
public void testUpdate() throws Exception{
  PersonService ps = new PersonService(getContext());
  ps.update(new Person(1,"xiaopang","18887654321",0));
}
public void testFind() throws Exception{
  PersonService ps = new PersonService(getContext());
  Person person = ps.find(1);
  Log.i("PersonService", person.toString());
}
public void testGetScrollData() throws Exception{
  PersonService ps = new PersonService(getContext());
  List<Person> persons = ps.getScrollData(3, 5);
  for(Person person:persons){
   Log.i("PersonService",person.toString());
  }
}

public void testGetCount() throws Exception{
  PersonService ps = new PersonService(getContext());
  Long count = ps.getCount();
  Log.i("PersonService",count.toString());
}
public void testUpdateAmount() throws Exception{
  PersonService ps = new PersonService(getContext());
  Person person1 = ps.find(1);
  Person person2 = ps.find(2);
  person1.setAmount(100);
  person2.setAmount(100);
  ps.update(person1);
  ps.update(person2);
}
public void testPayment() throws Exception{
  PersonService ps = new PersonService(getContext());
  ps.payment();
}
}

十三、OtherPersonServiceTest 单元测试类源码：

package com.example.test;

import java.util.List;

import com.example.domain.Person;
import com.example.service.DBOperateHelper;
import com.example.service.OtherPersonService;

import android.test.AndroidTestCase;
import android.util.Log;

public class OtherPersonServiceTest extends AndroidTestCase {
public void testCreateDB() throws Exception{
  DBOperateHelper dbHelper = new DBOperateHelper(getContext());
  dbHelper.getWritableDatabase();
}
public void testSave() throws Exception{
  OtherPersonService ps = new OtherPersonService(getContext());
  for(int i=1;i<=100;i++){
   Person person = new Person();
   person.setName("我是"+i);
   person.setPhone(String.valueOf(Long.parseLong("18888888800")+i));
   ps.save(person);
   Log.i("PersonService",person.toString());
  }
}
public void testDelete() throws Exception{
  OtherPersonService ps = new OtherPersonService(getContext());
  ps.delete(10);
}
public void testUpdate() throws Exception{
  OtherPersonService ps = new OtherPersonService(getContext());
  ps.update(new Person(1,"xiaopang","18887654321",0));
}
public void testFind() throws Exception{
  OtherPersonService ps = new OtherPersonService(getContext());
  Person person = ps.find(1);
  Log.i("PersonService", person.toString());
}
public void testGetScrollData() throws Exception{
  OtherPersonService ps = new OtherPersonService(getContext());
  List<Person> persons = ps.getScrollData(3, 5);
  for(Person person:persons){
   Log.i("PersonService",person.toString());
  }
}
public void testGetCount() throws Exception{
  OtherPersonService ps = new OtherPersonService(getContext());
  Long count = ps.getCount();
  Log.i("PersonService",count.toString());
}
}
十四、注意事项以及相关知识点：

1、掌握SQLite数据库如何创建数据库、建立表、维护字段等操作

继承SQLiteOpenHelper类，构造函数调用父类构造函数创建数据库，利用onCreate创建表，利用onUpgrade更新表字段信息

2、掌握SQLite数据库如何增、删、改、查以及分页

取得SQLiteDatabase的实例，然后调用该实例的方法可以完成上述操作

SQLiteDataBase提供两种操作上述功能的方式：一是直接调用execSQL书写sql语句，另一种是通过insert、update、delete、query等方法来传值来拼接sql，前一种适合熟练掌握sql 语句的

3、对需要数据同步的处理请添加事务处理，熟悉事务的处理方式

4、了解各个方法参数的意义以及传值

5、掌握ListView显示后台数据的使用方法

SimpleAdapter、SimpleCursorAdapter以及自定义适配器的使用，以及OnItemClickListener取值时各个适配器返回值的区别以及取值方法

6、多学、多记、多练、多思，加油！

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Android之怎么使用SQLite数据库(增、删、改、查、分页等)以及ListView显示数据

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