商品展示

1.代码

 

package cn.edu.bzu.shopshow.dao;import android.content.ContentValues;import android.content.Context;import android.database.Cursor;import android.database.sqlite.SQLiteDatabase;import java.util.ArrayList;import java.util.List;import cn.edu.bzu.shopshow.db.DBHelper;import cn.edu.bzu.shopshow.entity.Goods;/** * Created by Administrator on 2017/4/28. */public class GoodsDao {    private DBHelper dbHelper;    public GoodsDao(Context context){        dbHelper = new DBHelper(context,1);    }    public  void  add(Goods goods){        SQLiteDatabase sqLiteDatabase = dbHelper.getWritableDatabase();        ContentValues values = new ContentValues();        values.put("name",goods.getName());        values.put("amount",goods.getAmount());        long id = sqLiteDatabase.insert("goods",null,values);        goods.setId(id);        sqLiteDatabase.insert("goods",null,values);        sqLiteDatabase.close();    }    public int delete(long id){        SQLiteDatabase sqLiteDatabase = dbHelper.getWritableDatabase();        int count = sqLiteDatabase.delete("goods","_id=?",new String[]{id+""});        sqLiteDatabase.close();        return  count;    }    public int update(Goods goods){        int count;        SQLiteDatabase sqLiteDatabase = dbHelper.getWritableDatabase();        ContentValues values = new ContentValues();        values.put("name",goods.getName());        values.put("amount",goods.getAmount());        count =sqLiteDatabase.update("goods",values,"_id=?",new String[]{goods.getId()+""});        sqLiteDatabase.close();        return count;    }    public List<Goods> quertALL(){        List<Goods> goodsList = new ArrayList<>();        SQLiteDatabase sqLiteDatabase = dbHelper.getReadableDatabase();        Cursor cursor = sqLiteDatabase.query("goods",null,null,null,null,null,"amount desc");        while (cursor.moveToNext()){            long id = cursor.getLong(cursor.getColumnIndex("_id"));            String name = cursor.getString(cursor.getColumnIndex("name"));            int amount = cursor.getInt(cursor.getColumnIndex("amount"));            Goods goods = new Goods(id,amount,name);            goodsList.add(goods);        }        cursor.close();        sqLiteDatabase.close();        return  goodsList;    }}

package cn.edu.bzu.shopshow.db;import android.content.Context;import android.database.sqlite.SQLiteDatabase;import android.database.sqlite.SQLiteOpenHelper;/** * Created by Administrator on 2017/4/28. */public class DBHelper extends SQLiteOpenHelper {    public static final  String CREATE_GOODS = "create table goods(_id integer primary key autoincrement , name varchar(20) , amount integer)"; //建表语句    public DBHelper(Context context, int version) {        super(context,"goods.db",null, version);    }    @Override    public void onCreate(SQLiteDatabase db) {        db.execSQL(CREATE_GOODS);    }    @Override    public void onUpgrade(SQLiteDatabase sqLiteDatabase, int i, int i1) {    }}

package cn.edu.bzu.shopshow;import android.content.Context;import android.support.annotation.NonNull;import android.view.LayoutInflater;import android.view.View;import android.view.ViewGroup;import android.widget.ArrayAdapter;import android.widget.ImageView;import android.widget.TextView;import java.util.List;import cn.edu.bzu.shopshow.entity.Goods;/** * Created by Administrator on 2017/4/28. */public class GoodsAdapter  extends ArrayAdapter<Goods>{    private int resourceId;    public GoodsAdapter(Context context, int resource,  List<Goods> objects) {        super(context, resource, objects);        resourceId = resource;    }    @NonNull    @Override    public View getView(int position, View convertView, ViewGroup parent) {  //对应数据放到相应空间上        Goods goods = getItem(position);        View view = null;        ViewHolder viewHolder;        if(convertView==null){            view = LayoutInflater.from(getContext()).inflate(R.layout.item,null);            viewHolder = new ViewHolder();            viewHolder.tvId = (TextView) view.findViewById(R.id.tvID);            viewHolder.tvName = (TextView) view.findViewById(R.id.tvName);            viewHolder.tvAmount = (TextView) view.findViewById(R.id.tvAmount);            viewHolder.ivUp = (ImageView) view.findViewById(R.id.ivUp);            viewHolder.ivDown = (ImageView) view.findViewById(R.id.ivDown);            viewHolder.ivDelete = (ImageView) view.findViewById(R.id.ivdelete);            view.setTag(viewHolder);        }else        {            view = convertView;            viewHolder = (ViewHolder)view.getTag();        }        viewHolder.tvId.setText(goods.getId()+"         ");        viewHolder.tvName.setText(goods.getName()+"         ");        viewHolder.tvAmount.setText(goods.getAmount()+"         ");        return view;    }    class ViewHolder{        TextView tvId;        TextView tvName;        TextView tvAmount;        ImageView ivUp;        ImageView ivDown;        ImageView ivDelete;    }}

package cn.edu.bzu.shopshow.entity;/** * Created by Administrator on 2017/4/28. */public class Goods {    private Long id;    private String name;    private int amount;    public Goods(long id, int amount, String name) {        this.id = id;        this.amount = amount;        this.name = name;    }    public Goods(String name, int amount) {        this.name = name;        this.amount = amount;    }    public Long getId() {        return id;    }    public void setId(Long id) {        this.id = id;    }    public String getName() {        return name;    }    public void setName(String name) {        this.name = name;    }    public int getAmount() {        return amount;    }    public void setAmount(int amount) {        this.amount = amount;    }    @Override    public String toString() {        return "Goods{" + "id=" + id + ", name='" + name + '\'' + ", amount=" + amount + '}';    }}

package cn.edu.bzu.shopshow;import android.support.v7.app.AppCompatActivity;import android.os.Bundle;import android.text.TextUtils;import android.view.View;import android.widget.EditText;import android.widget.ListView;import android.widget.Toast;import java.util.List;import cn.edu.bzu.shopshow.dao.GoodsDao;import cn.edu.bzu.shopshow.entity.Goods;public class MainActivity extends AppCompatActivity {    private EditText etName;    private EditText etAmount;    private ListView lvGoods;    private GoodsAdapter goodsAdapter;    private GoodsDao goodsDao;    private List<Goods> goodsList;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        etName = (EditText) findViewById(R.id.etName);        etAmount = (EditText) findViewById(R.id.etAmount);        lvGoods = (ListView) findViewById(R.id.lvGoods);        goodsDao = new GoodsDao(this);        goodsList = goodsDao.quertALL();        goodsAdapter = new GoodsAdapter(this,R.layout.item,goodsList);        lvGoods.setAdapter(goodsAdapter);    }    public  void addGoods(View view)    {        String name = etName.getText().toString();        String amount = etAmount.getText().toString();        if(TextUtils.isEmpty(name)||TextUtils.isEmpty(amount))            return ;       // Goods goods = new Goods(name,amount.equals("")?0:Integer.parseInt(amount));        Goods goods = new Goods(name,Integer.parseInt(amount));        goodsDao.add(goods);        goodsAdapter.notifyDataSetChanged();        goodsList.add(goods);        etName.setText("");        etAmount.setText("");        Toast.makeText(this,"添加成功",Toast.LENGTH_LONG);    }}

<?xml version="1.0" encoding="utf-8"?><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"    android:layout_width="match_parent"    android:layout_height="match_parent">    <TextView        android:text="1"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:id="@+id/tvID"        android:textSize="20sp"        android:gravity="left"        android:layout_weight="1" />    <TextView        android:text="商品名称"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:id="@+id/tvName"        android:gravity="left"        android:textSize="20sp"        android:maxLines="1"        android:layout_weight="1"/>    <TextView        android:text="商品金额"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:id="@+id/tvAmount"        android:gravity="left"        android:textSize="20sp"        android:maxLines="1"        android:layout_weight="1"/><LinearLayout    android:layout_width="wrap_content"    android:layout_height="wrap_content"    android:orientation="vertical">    <ImageView        android:id="@+id/ivUp"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:src="@android:drawable/arrow_up_float"/>    <ImageView        android:id="@+id/ivDown"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:src="@android:drawable/arrow_down_float"/></LinearLayout>    <ImageView        android:id="@+id/ivdelete"        android:layout_width="25dp"        android:layout_height="25dp"        android:src="@android:drawable/ic_menu_delete"/></LinearLayout>

<?xml version="1.0" encoding="utf-8"?><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"    xmlns:tools="http://schemas.android.com/tools"    android:id="@+id/activity_main"    android:layout_width="match_parent"    android:layout_height="match_parent"    android:orientation="vertical"    tools:context="cn.edu.bzu.shopshow.MainActivity"><LinearLayout    android:layout_width="match_parent"    android:layout_height="wrap_content">    <EditText        android:id="@+id/etName"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:hint="商品名称"        android:inputType="text"        android:layout_weight="1"/>    <EditText        android:id="@+id/etAmount"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:hint="商品金额"        android:inputType="number"        android:layout_weight="1"/>    <ImageView        android:id="@+id/ivAdd"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:onClick="addGoods"        android:src="@android:drawable/ic_input_add"/></LinearLayout>    <ListView        android:id="@+id/lvGoods"        android:layout_width="wrap_content"        android:layout_height="match_parent" /></LinearLayout>

2.效果图




3.结构