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当然做完一大堆功能还是离不开数据库的支持,还需要将操作数据封装调用数据库代码才能将数据储存。
封装数据代码
package com.example.notebook; import java.io.Serializable; import android.R.integer; public class Notelist implements Serializable { private int id; private String titleString,eventString,dateString; public int getId() { return id; } public void setId(int id) { this.id = id; } public String getTitleString() { return titleString; } public void setTitleString(String titleString) { this.titleString = titleString; } public String getEventString() { return eventString; } public void setEventString(String eventString) { this.eventString = eventString; } public String getDateString() { return dateString; } public void setDateString(String dateString) { this.dateString = dateString; } public Notelist(int id, String titleString, String eventString, String dateString) { super(); this.id = id; this.titleString = titleString; this.eventString = eventString; this.dateString = dateString; } public Notelist() { // TODO Auto-generated constructor stub } }
调用的数据库代码
package com.example.notebook; import android.R.integer; import android.content.Context; import android.database.Cursor; import android.database.sqlite.SQLiteDatabase; import android.database.sqlite.SQLiteDatabase.CursorFactory; import android.database.sqlite.SQLiteOpenHelper; /*----------------------------------数据库语句------------------------------------*/ public class MydatabaseHelper extends SQLiteOpenHelper { //1.定义数据库名称 private static String DATABASENAME="personal.db"; //2.定义数据库版本 private static int DATABASEVERSION=1; public MydatabaseHelper(Context context) { super(context, DATABASENAME, null, DATABASEVERSION); } @Override public void onCreate(SQLiteDatabase arg0) { // TODO Auto-generated method stub //1.构建创建用户注册信息数据表语句 String sqlString="CREATE TABLE register ("+ "id INTEGER PRIMARY KEY AUTOINCREMENT,"+ "name VARCHAR( 8 ),"+ "pwd VARCHAR( 14 ) "+ ");"; //2.执行构造好的语句 arg0.execSQL(sqlString); //创建笔记事件记录的表 sqlString="CREATE TABLE event ( "+ "id INTEGER PRIMARY KEY AUTOINCREMENT,"+ "title TEXT( 30 ),"+ "events TEXT( 255 ),"+ "date DATE "+ ");"; arg0.execSQL(sqlString); //构建笔记事件备份的表 sqlString="CREATE TABLE eventbackup ( "+ "title TEXT( 30 ),"+ "events TEXT( 255 ),"+ "date DATE "+ ");"; arg0.execSQL(sqlString); } //当用户通过注册页面注册,通过此方法将注册信息插入表中。 public void insert(String nameString,String pwdString) { SQLiteDatabase db=super.getWritableDatabase(); String sqlString="insert into register(name,pwd) values('"+nameString+"','"+pwdString+"')"; db.execSQL(sqlString); db.close(); } //当用户添加了记事之后,通过此方法插入到表中。 public void eventsinsert(String titleString,String evntsString,String timeString) { SQLiteDatabase db=super.getWritableDatabase(); String sqlString="insert into event(title,events,date) values('"+titleString+"','"+evntsString+"','"+timeString+"')"; db.execSQL(sqlString); db.close(); } //通过游标方法查找用户注册信息 public Cursor findCousor(){ SQLiteDatabase db=getWritableDatabase(); String sqlString="select name,pwd from register"; Cursor resultCursor=db.rawQuery(sqlString, null); return resultCursor; } //通过游标方法查找事件记录信息 public Cursor findnoteCursor(){ SQLiteDatabase db=super.getReadableDatabase(); String sqlString="select id,title,events,date from event"; Cursor resultCursor = db.rawQuery(sqlString, null); return resultCursor; } //当用户修改了记事之后通过此方法修改数据库里面的记录 public void eventsupdate(String idString,String titleString,String eventsString,String dateString) { SQLiteDatabase db=getWritableDatabase(); String sqlString="update event set title='"+titleString+"',events='"+eventsString+"',date='"+dateString+"' where id="+idString; db.execSQL(sqlString); db.close(); } //当用户删除记事之后通过此方法删除数据库里面的记事 public void eventdelete(int id) { SQLiteDatabase db=getWritableDatabase(); String sqlString="delete from event where id="+id; db.execSQL(sqlString); db.close(); } //查找事件记录 public Cursor getAllnote() { SQLiteDatabase db=super.getReadableDatabase(); String sqlString="select id,title,events,date from event"; Cursor resultCursor = db.rawQuery(sqlString, null); return resultCursor; } //数据库备份 public void backup() { SQLiteDatabase db=getWritableDatabase(); String sqlString="insert into eventbackup select title,events,date from event"; db.execSQL(sqlString); db.close(); } //删除原备份 public void backupdelete() { SQLiteDatabase db=getWritableDatabase(); String sqlString="delete from eventbackup"; db.execSQL(sqlString); db.close(); } //数据库还原 public void recover() { SQLiteDatabase db=getWritableDatabase(); String sqlString="insert into event(title,events,date) select title,events,date from eventbackup"; db.execSQL(sqlString); db.close(); } //删除原数据 public void recoverdelete() { SQLiteDatabase db=getWritableDatabase(); String sqlString="delete from event"; db.execSQL(sqlString); db.close(); } @Override public void onUpgrade(SQLiteDatabase arg0, int arg1, int arg2) { // TODO Auto-generated method stub } }
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