今天就跟大家聊聊有关android studio数据存储建立SQLite数据库怎么实现增删查改,可能很多人都不太了解,为了让大家更加了解,小编给大家总结了以下内容,希望大家根据这篇文章可以有所收获。
实验目的:
分别使用sqlite3
工具和Android
代码的方式建立SQLite
数据库。在完成建立数据库的工作后,编程实现基本的数据库操作功能,包括数据的添加、删除和更新。
实验要求:
1.创建一个学生管理的应用,基本信息包含学生姓名,班级,学号。采用数据库存储这些信息。
2.应用应该至少包含信息录入和删除功能。
3.数据显示考虑采用ListView。
实验效果:
工程结构:
源代码:
DBAdapter.java
package com.example.shiyan6_sqlite; import android.annotation.SuppressLint; import android.content.ContentValues; import android.content.Context; import android.database.Cursor; import android.database.sqlite.SQLiteDatabase; import android.database.sqlite.SQLiteException; import android.database.sqlite.SQLiteOpenHelper; import android.database.sqlite.SQLiteDatabase.CursorFactory; public class DBAdapter { private static final String DB_NAME = "student.db"; private static final String DB_TABLE = "peopleinfo"; private static final int DB_VERSION = 1; public static final String KEY_ID = "_id"; public static final String KEY_NAME = "name"; public static final String KEY_BANJI = "banji"; public static final String KEY_XUEHAO = "xuehao"; private SQLiteDatabase db; private final Context context; private DBOpenHelper dbOpenHelper; public DBAdapter(Context _context) { context = _context; } public void close() { if(db !=null) { db.close(); db=null; } } public void open() throws SQLiteException { dbOpenHelper = new DBOpenHelper(context, DB_NAME, null, DB_VERSION); try { db = dbOpenHelper.getWritableDatabase(); } catch (SQLiteException ex) { db = dbOpenHelper.getReadableDatabase(); } } public long insert(People people) { ContentValues newValues = new ContentValues(); newValues.put(KEY_NAME, people.Name); newValues.put(KEY_BANJI, people.Banji); newValues.put(KEY_XUEHAO, people.Xuehao); return db.insert(DB_TABLE, null, newValues); } public People[] queryAllData() { Cursor results = db.query(DB_TABLE, new String[] { KEY_ID, KEY_NAME, KEY_BANJI, KEY_XUEHAO}, null, null, null, null, null); return ConvertToPeople(results); } public People[] queryOneData(long id) { Cursor results = db.query(DB_TABLE, new String[] { KEY_ID, KEY_NAME, KEY_BANJI, KEY_XUEHAO}, KEY_ID + "=" + id, null, null, null, null); return ConvertToPeople(results); } @SuppressLint("Range") private People[] ConvertToPeople(Cursor cursor){ int resultCounts = cursor.getCount(); if (resultCounts == 0 || !cursor.moveToFirst()){ return null; } People[] peoples = new People[resultCounts]; for (int i = 0 ; i<resultCounts; i++){ peoples[i] = new People(); peoples[i].ID = cursor.getInt(0); peoples[i].Name = cursor.getString(cursor.getColumnIndex(KEY_NAME)); peoples[i].Banji = cursor.getString(cursor.getColumnIndex(KEY_BANJI)); peoples[i].Xuehao = cursor.getString(cursor.getColumnIndex(KEY_XUEHAO)); cursor.moveToNext(); } return peoples; } public long deleteAllData() { return db.delete(DB_TABLE, null, null); } public long deleteOneData(long id) { return db.delete(DB_TABLE, KEY_ID + "=" + id, null); } public long updateOneData(long id , People people){ ContentValues updateValues = new ContentValues(); updateValues.put(KEY_NAME, people.Name); updateValues.put(KEY_BANJI, people.Banji); updateValues.put(KEY_XUEHAO, people.Xuehao); return db.update(DB_TABLE, updateValues, KEY_ID + "=" + id, null); } private static class DBOpenHelper extends SQLiteOpenHelper { public DBOpenHelper(Context context, String name, CursorFactory factory, int version) { super(context, name, factory, version); } private static final String DB_CREATE = "create table " + DB_TABLE + " (" + KEY_ID + " integer primary key autoincrement, " + KEY_NAME+ " text not null, " + KEY_BANJI+ " text not null," + KEY_XUEHAO + " text not null);"; @Override public void onCreate(SQLiteDatabase _db) { _db.execSQL(DB_CREATE); } @Override public void onUpgrade(SQLiteDatabase _db, int _oldVersion, int _newVersion) { _db.execSQL("DROP TABLE IF EXISTS " + DB_TABLE); onCreate(_db); } } }android studio数据存储建立SQLite数据库怎么实现增删查改