Android课程设计之校园二手交易app源码.zip

package com.leaf.collegeidleapp.util; import android.content.ContentValues; import android.content.Context; import android.database.Cursor; import android.database.sqlite.SQLiteDatabase; import android.database.sqlite.SQLiteOpenHelper; import com.leaf.collegeidleapp.bean.Commodity; import java.util.ArrayList; import java.util.LinkedList; import java.util.List; /** * 商品数据库连接类 * @author : autumn_leaf */ public class CommodityDbHelper extends SQLiteOpenHelper { //定义商品表 public static final String DB_NAME = "tb_commodity"; /**创建商品表*/ private static final String CREATE_COMMODITY_DB = "create table tb_commodity(" + "id integer primary key autoincrement," + "title text," + "category text," + "price float," + "phone text," + "description text," + "picture blob," + "stuId text)"; public CommodityDbHelper(Context context, String name, SQLiteDatabase.CursorFactory factory, int version) { super(context, name, factory, version); } @Override public void onCreate(SQLiteDatabase db) { db.execSQL(CREATE_COMMODITY_DB); } @Override public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) { } /** * 添加物品方法 * @param commodity 物品对象 */ public boolean AddCommodity(Commodity commodity) { SQLiteDatabase db = this.getWritableDatabase(); ContentValues values = new ContentValues(); values.put("title",commodity.getTitle()); values.put("category",commodity.getCategory()); values.put("price",commodity.getPrice()); values.put("phone",commodity.getPhone()); values.put("description",commodity.getDescription()); values.put("picture",commodity.getPicture()); values.put("stuId",commodity.getStuId()); db.insert(DB_NAME,null,values); values.clear(); return true; } /** * 通过学号查找我的发布物品信息 * @param stuId 学生学号 * @return 查找到的物品 */ public List<Commodity> readMyCommodities(String stuId) { List<Commodity> myCommodities = new ArrayList<>(); SQLiteDatabase db = this.getWritableDatabase(); Cursor cursor = db.rawQuery("select * from tb_commodity where stuId=?",new String[]{stuId}); if(cursor.moveToFirst()) { do { String title = cursor.getString(cursor.getColumnIndex("title")); String category = cursor.getString(cursor.getColumnIndex("category")); float price = cursor.getFloat(cursor.getColumnIndex("price")); String phone = cursor.getString(cursor.getColumnIndex("phone")); String description = cursor.getString(cursor.getColumnIndex("description")); byte[] picture = cursor.getBlob(cursor.getColumnIndex("picture")); Commodity commodity = new Commodity(); commodity.setTitle(title); commodity.setCategory(category); commodity.setPrice(price); commodity.setDescription(description); commodity.setPhone(phone); commodity.setPicture(picture); myCommodities.add(commodity); }while (cursor.moveToNext()); } cursor.close(); return myCommodities; } /** * 获取所有的商品信息 * @return 所有的商品列表 */ public List<Commodity> readAllCommodities() { List<Commodity> allCommodities = new ArrayList<>(); SQLiteDatabase db = this.getWritableDatabase(); Cursor cursor = db.rawQuery("select * from tb_commodity order by price",null); if(cursor.moveToFirst()) { do { String title = cursor.getString(cursor.getColumnIndex("title")); String category = cursor.getString(cursor.getColumnIndex("category")); float price = cursor.getFloat(cursor.getColumnIndex("price")); String phone = cursor.getString(cursor.getColumnIndex("phone")); String description = cursor.getString(cursor.getColumnIndex("description")); byte[] picture = cursor.getBlob(cursor.getColumnIndex("picture")); String stuId = cursor.getString(cursor.getColumnIndex("stuId")); Commodity commodity = new Commodity(); commodity.setTitle(title); commodity.setCategory(category); commodity.setPrice(price); commodity.setDescription(description); commodity.setPhone(phone); commodity.setPicture(picture); commodity.setStuId(stuId); allCommodities.add(commodity); }while (cursor.moveToNext()); } cursor.close(); return allCommodities; } /** * 根据商品名称删除商品 * @param title 商品名称 * @param description 商品描述 * @param price 商品价格 */ public void deleteMyCommodity(String title,String description,float price) { SQLiteDatabase db = this.getWritableDatabase(); if(db.isOpen()) { db.delete(DB_NAME,"title=? and description=? and price=?",new String[]{title,description,String.valueOf(price)}); db.close(); } } /** * 读取不同类别的商品信息 * @param category 类别 * @return 商品列表 */ public List<Commodity> readCommodityType(String category) { List<Commodity> differentTypes = new ArrayList<>(); SQLiteDatabase db = this.getWritableDatabase(); Cursor cursor = db.rawQuery("select * from tb_commodity where category=?",new String[]{category}); if(cursor.moveToFirst()) { do{ String title = cursor.getString(cursor.getColumnIndex("title")); float price = cursor.getFloat(cursor.getColumnIndex("price")); String description = cursor.getString(cursor.getColumnIndex("description")); byte[] picture = cursor.getBlob(cursor.getColumnIndex("picture")); Commodity commodity = new Commodity(); commodity.setTitle(title); commodity.setPrice(price); commodity.setCategory(category); commodity.setDescription(description); commodity.setPicture(picture); differentTypes.add(commodity); }while (cursor.moveToNext()); } cursor.close(); return differentTypes; } }