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Android中SQLite的使用
<1>创建数据库
<2>更新数据库
<3>删除数据库
<4>创建数据表
<5>删除数据表
<6>增加数据
<7>更新数据
<8>删除数据
strings.xml
<?xml version="1.0" encoding="utf-8"?>
<resources>
<string name="app_name">SQLite</string>
<string name="careteDataBase">创建数据库</string>
<string name="updateDataBase">更新数据库</string>
<string name="deleteDataBase">删除数据库</string>
<string name="createTable">创建数据表</string>
<string name="deleteTable">删除数据表</string>
<string name="insertData">增加数据</string>
<string name="updateData">更新数据</string>
<string name="selectData">查询数据</string>
<string name="deleteData">删除数据</string>
</resources>
main.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical" android:layout_width="fill_parent"
android:layout_height="fill_parent">
<!-- 创建数据库 -->
<Button android:id="@+id/careteDataBaseButtonId"
android:layout_width="fill_parent" android:layout_height="wrap_content"
android:layout_margin="10px" android:layout_gravity="center"
android:gravity="center" android:text="@string/careteDataBase" />
<!-- 更新数据库 -->
<Button android:id="@+id/updateDataBaseButtonId"
android:layout_width="fill_parent" android:layout_height="wrap_content"
android:layout_margin="10px" android:layout_gravity="center"
android:gravity="center" android:text="@string/updateDataBase" />
<!-- 删除数据库 -->
<Button android:id="@+id/deleteDataBaseButtonId"
android:layout_width="fill_parent" android:layout_height="wrap_content"
android:layout_margin="10px" android:layout_gravity="center"
android:gravity="center" android:text="@string/deleteDataBase" />
<!-- 创建数据表 -->
<Button android:id="@+id/createTableButtonId"
android:layout_width="fill_parent" android:layout_height="wrap_content"
android:layout_margin="10px" android:layout_gravity="center"
android:gravity="center" android:text="@string/createTable" />
<!-- 删除数据表 -->
<Button android:id="@+id/deleteTableButtonId"
android:layout_width="fill_parent" android:layout_height="wrap_content"
android:layout_margin="10px" android:layout_gravity="center"
android:gravity="center" android:text="@string/deleteTable" />
<!-- 增加数据 -->
<Button android:id="@+id/insertDataButtonId"
android:layout_width="fill_parent" android:layout_height="wrap_content"
android:layout_margin="10px" android:layout_gravity="center"
android:gravity="center" android:text="@string/insertData" />
<!-- 更新数据 -->
<Button android:id="@+id/updateDataButtonId"
android:layout_width="fill_parent" android:layout_height="wrap_content"
android:layout_margin="10px" android:layout_gravity="center"
android:gravity="center" android:text="@string/updateData" />
<!-- 查询操作 -->
<Button android:id="@+id/selectDataButtonId"
android:layout_width="fill_parent" android:layout_height="wrap_content"
android:layout_margin="10px" android:layout_gravity="center"
android:gravity="center" android:text="@string/selectData" />
<!-- 删除操作 -->
<Button android:id="@+id/deleteDataButtonId"
android:layout_width="fill_parent" android:layout_height="wrap_content"
android:layout_margin="10px" android:layout_gravity="center"
android:gravity="center" android:text="@string/deleteData" />
</LinearLayout>
SQLiteActivity.java
package com.duoguo.android;
import android.app.Activity;
import android.content.ContentValues;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import com.duoguo.sql.DataBaseHelpr;
/**
* Android系统中的增删查该等操作
*
* @author shyboy(897948924@qq.com)
*
*/
public class SQLiteActivity extends Activity {
// 声明Button控件
private Button createDataBaseButton;
private Button updateDataBaseButton;
private Button deleteDataBaseButton;
private Button createTableButton;
private Button deleteTableButton;
private Button insertDataButton;
private Button updataDataButton;
private Button selectDataButton;
private Button deleteDataButton;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
// 通过控件的ID获取Button控件对象
createDataBaseButton = (Button) findViewById(R.id.careteDataBaseButtonId);
updateDataBaseButton = (Button) findViewById(R.id.updateDataBaseButtonId);
deleteDataBaseButton = (Button) findViewById(R.id.deleteDataBaseButtonId);
createTableButton = (Button) findViewById(R.id.createTableButtonId);
deleteTableButton = (Button) findViewById(R.id.deleteTableButtonId);
insertDataButton = (Button) findViewById(R.id.insertDataButtonId);
updataDataButton = (Button) findViewById(R.id.updateDataButtonId);
selectDataButton = (Button) findViewById(R.id.selectDataButtonId);
deleteDataButton = (Button) findViewById(R.id.deleteDataButtonId);
createDataBaseButton
.setOnClickListener(new CreateDataBaseClickListener());// 为创建数据库添加单击事件监听器
updateDataBaseButton
.setOnClickListener(new UpdateDataBaseClickListener());// 为更新数据库添加单击事件监听器
deleteDataBaseButton
.setOnClickListener(new DeleteDataBaseClickListener());// 为删除数据库添加单击事件监听器
createTableButton.setOnClickListener(new CreateTableClickListener());// 为创建数据表添加单击事件监听器
deleteTableButton.setOnClickListener(new DeleteTableClickListener());// 为删除数据表添加单击事件监听器
insertDataButton.setOnClickListener(new InsertDataClickListener());// 为增加数据添加单击事件监听器
updataDataButton.setOnClickListener(new UpdateDataClickListener());// 为更新数据添加单击事件监听器
selectDataButton.setOnClickListener(new SelectDataClickListener());// 为查询数据添加单击事件监听器
deleteDataButton.setOnClickListener(new DeleteDataClickListener());// 为删除数据添加单击事件监听器
}
// 创建数据库监听器
class CreateDataBaseClickListener implements OnClickListener {
@Override
public void onClick(View v) {
DataBaseHelpr dataBaseHelpr = new DataBaseHelpr(
SQLiteActivity.this, "user_db");// 实例化DataBaseHelpr对象
dataBaseHelpr.getReadableDatabase();// 创建数据库
}
}
// 更新数据库监听器
class UpdateDataBaseClickListener implements OnClickListener {
@Override
public void onClick(View v) {
DataBaseHelpr dataBaseHelpr = new DataBaseHelpr(
SQLiteActivity.this, "user_db", 2);// 实例化DataBaseHelpr对象
dataBaseHelpr.getReadableDatabase();// 更新数据库
}
}
// 删除数据库监听器
class DeleteDataBaseClickListener implements OnClickListener {
@Override
public void onClick(View v) {
System.out.println("delete database");
boolean success = deleteDatabase("user_db");
if (success) {
System.out.println("delete successfully");
} else {
System.out.println("delete unsuccessfully");
}
}
}
// 创建数据表监听器
class CreateTableClickListener implements OnClickListener {
@Override
public void onClick(View v) {
System.out.println("create table");
DataBaseHelpr dataBaseHelpr = new DataBaseHelpr(
SQLiteActivity.this, "user_db");// 实例化DataBaseHelpr对象
SQLiteDatabase sqLiteDatabase = dataBaseHelpr.getWritableDatabase();// 获取SQLiteDatabase对象
sqLiteDatabase
.execSQL("create table user(id int,name varchar(20))");// 创建数据表
}
}
// 删除数据表监听器
class DeleteTableClickListener implements OnClickListener {
@Override
public void onClick(View v) {
System.out.println("delete table");
DataBaseHelpr dataBaseHelpr = new DataBaseHelpr(
SQLiteActivity.this, "user_db");// 实例化DataBaseHelpr对象
SQLiteDatabase sqLiteDatabase = dataBaseHelpr.getWritableDatabase();// 获取SQLiteDatabase对象
sqLiteDatabase.execSQL("drop table if exists user");// 删除数据表
}
}
// 增加数据监听器
class InsertDataClickListener implements OnClickListener {
@Override
public void onClick(View v) {
System.out.println("insert data");
ContentValues contentValues = new ContentValues();// 实例化ContentValues对象
// 向数据表中插入相应的数据,其中key是列名,value是列名对应的值
contentValues.put("id", 1);
contentValues.put("name", "shyboy");
DataBaseHelpr dataBaseHelpr = new DataBaseHelpr(
SQLiteActivity.this, "user_db");// 实例化DataBaseHelpr对象
SQLiteDatabase sqLiteDatabase = dataBaseHelpr.getWritableDatabase();// 获取SQLiteDatabase对象,因要插入相应的数据,故获取可写入的
sqLiteDatabase.insert("user", null, contentValues);// 增加数据
}
}
// 更新数据监听器
class UpdateDataClickListener implements OnClickListener {
@Override
public void onClick(View v) {
System.out.println("update data");
DataBaseHelpr dataBaseHelpr = new DataBaseHelpr(
SQLiteActivity.this, "user_db");// 实例化DataBaseHelpr对象
SQLiteDatabase sqLiteDatabase = dataBaseHelpr.getWritableDatabase();// 获取SQLiteDatabase对象,因要更新相应的数据,故获取可写入的
ContentValues contentValues = new ContentValues();// 实例化ContentValues对象
contentValues.put("name", "playboy");
sqLiteDatabase.update("user", contentValues, "id=?",
new String[] { "1" });// 更新数据,其中参数一为表名,参数二为修改的值,参数三为修改的条件,参数四位修改的条件值
}
}
// 查询数据监听器
class SelectDataClickListener implements OnClickListener {
@Override
public void onClick(View v) {
System.out.println("select data");
DataBaseHelpr dataBaseHelpr = new DataBaseHelpr(
SQLiteActivity.this, "user_db");// 实例化DataBaseHelpr对象
SQLiteDatabase sqLiteDatabase = dataBaseHelpr.getReadableDatabase();// 获取SQLiteDatabase对象
Cursor cursor = sqLiteDatabase.query("user", new String[] { "id",
"name" }, "id=?", new String[] { "1" }, null, null, null);// 查询数据
while (cursor.moveToNext()) {
int id = cursor.getInt(cursor.getColumnIndex("id"));// 获取编号
System.out.println("id:" + id);
String name = cursor.getString(cursor.getColumnIndex("name"));// 获取名称
System.out.println("name:" + name);
}
}
}
// 删除数据监听器
class DeleteDataClickListener implements OnClickListener {
@Override
public void onClick(View v) {
System.out.println("delete data");
DataBaseHelpr dataBaseHelpr = new DataBaseHelpr(
SQLiteActivity.this, "user_db");// 实例化DataBaseHelpr对象
SQLiteDatabase sqLiteDatabase = dataBaseHelpr.getWritableDatabase();// 获取SQLiteDatabase对象
sqLiteDatabase.delete("user", "id=?", new String[] { "1" });// 删除数据
}
}
}
DataBaseHelpr.java
/**
*
*/
package com.duoguo.sql;
import android.content.Context;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteDatabase.CursorFactory;
import android.database.sqlite.SQLiteOpenHelper;
/**
* SQLiteOpenHelper的使用
*
* @author shyboy(897948924@qq.com)
*
*/
public class DataBaseHelpr extends SQLiteOpenHelper {
private static final int VERSION = 1;// 声明数据库的版本为1
/**
* 第一构造方法
*
* @param context
* :当前的Activity
* @param name
* :数据库名称
* @param factory
* :用于查询时返回相应的值
* @param version
* :数据库版本
*/
public DataBaseHelpr(Context context, String name, CursorFactory factory,
int version) {
super(context, name, factory, version);// 继承父类的构造方法
}
/**
* 第二构造方法
*
* @param context
* :当前的Activity
* @param name
* :数据库名称
* @param version
* :数据库版本
*/
public DataBaseHelpr(Context context, String name, int version) {
this(context, name, null, version);// 调用第一构造方法
}
/**
* 第三构造方法
*
* @param context
* :当前的Activity
* @param name
* :数据库名称
*/
public DataBaseHelpr(Context context, String name) {
this(context, name, VERSION);// 调用第二构造方法
}
/*
* (non-Javadoc)
*
* @see
* android.database.sqlite.SQLiteOpenHelper#onCreate(android.database.sqlite
* .SQLiteDatabase) 该方法在第一次创建数据库时执行,用于创建数据表
*/
@Override
public void onCreate(SQLiteDatabase arg0) {
System.out.println("create a database");
arg0.execSQL("create table user(id int,name varchar(20))");// 执行sql语句
}
/*
* (non-Javadoc)
*
* @see
* android.database.sqlite.SQLiteOpenHelper#onUpgrade(android.database.sqlite
* .SQLiteDatabase, int, int) 该方法用于更新数据库
*/
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
System.out.println("update a database");
}
}
希望对你有所帮助 |
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