商品展示

   1.GoodsDao

   

package cn.bzu.edu.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.bzu.edu.shopshow.dao.GoodsDao;import cn.bzu.edu.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);        goodsDao=new GoodsDao(this);        goodsList=goodsDao.queryAll();        goodsAdapter=new GoodsAdapter(this,R.layout.item,goodsList,goodsDao);        lvGoods=(ListView)findViewById(R.id.lvGoods);        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,Integer.parseInt(amount));        goodsDao.add(goods);        goodsList.add(goods);        goodsAdapter.notifyDataSetChanged();        etName.setText("");        etAmount.setText("");        Toast.makeText(this,"添加成功",Toast.LENGTH_LONG).show();    }}

2.DBHelper

  

package cn.bzu.edu.shopshow.db;import android.content.Context;import android.database.sqlite.SQLiteDatabase;import android.database.sqlite.SQLiteOpenHelper;/** * Created by Administrator on 2017/4/27. */public class DBHelper extends SQLiteOpenHelper {    public static final String CREATE_GOODS="create table goods(_id integer primary key autoincrement,name varchar(20),amount integer)";    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 db, int oldVersion, int newVersion) {    }}

3.GoodsAdapter

package cn.bzu.edu.shopshow;import android.content.Context;import android.content.DialogInterface;import android.support.annotation.NonNull;import android.support.v7.app.AlertDialog;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.bzu.edu.shopshow.dao.GoodsDao;import cn.bzu.edu.shopshow.entity.Goods;/** * Created by Administrator on 2017/4/27. */public class GoodsAdapter extends ArrayAdapter<Goods>{    private int resounceId;    private GoodsDao goodsDao;    private List<Goods> goodsList;    public GoodsAdapter(Context context, int resource, List<Goods> objects, GoodsDao goodsDao) {        super(context, resource, objects);        resounceId=resource;        goodsList=objects;        this.goodsDao=goodsDao;    }    @NonNull    @Override    public View getView(int position, View convertView, ViewGroup parent) {        final Goods goods=getItem(position);        View view=null;        ViewHolder viewHolder;        if (convertView==null){            view=LayoutInflater.from(getContext()).inflate(resounceId,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.ivDowm=(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()+"");        viewHolder.ivDelete.setOnClickListener(new View.OnClickListener(){            @Override            public void onClick(View v){                AlertDialog.Builder builder=new AlertDialog.Builder(getContext());                builder.setTitle("你确定要删除吗？");                builder.setPositiveButton("yes", new DialogInterface.OnClickListener() {                    @Override                    public void onClick(DialogInterface dialog, int which) {                        goodsList.remove(goods);                        goodsDao.delete(goods.getId());                        notifyDataSetChanged();                    }                });                builder.setNegativeButton("cancle",null);                builder.show();            }        });        viewHolder.ivUp.setOnClickListener(new View.OnClickListener() {            @Override            public void onClick(View v) {                goods.setAmount(goods.getAmount()-1);                goodsDao.update(goods);                notifyDataSetChanged();            }        });        viewHolder.ivDowm.setOnClickListener(new View.OnClickListener() {            @Override            public void onClick(View v) {                goods.setAmount(goods.getAmount()+1);                goodsDao.update(goods);                notifyDataSetChanged();            }        });        return view;    }    class ViewHolder{        TextView tvId;        TextView tvName;        TextView tvAmount;        ImageView ivUp;        ImageView ivDowm;        ImageView ivDelete;    }}

4.MainActivity

package cn.bzu.edu.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.bzu.edu.shopshow.dao.GoodsDao;import cn.bzu.edu.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);        goodsDao=new GoodsDao(this);        goodsList=goodsDao.queryAll();        goodsAdapter=new GoodsAdapter(this,R.layout.item,goodsList,goodsDao);        lvGoods=(ListView)findViewById(R.id.lvGoods);        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,Integer.parseInt(amount));        goodsDao.add(goods);        goodsList.add(goods);        goodsAdapter.notifyDataSetChanged();        etName.setText("");        etAmount.setText("");        Toast.makeText(this,"添加成功",Toast.LENGTH_LONG).show();    }}

5.activity_main.xml

<?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"    android:layout_margin="8dp"    tools:context="cn.bzu.edu.shopshow.MainActivity">    <LinearLayout        android:id="@+id/llAdd"        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:orientation="horizontal">        <EditText            android:id="@+id/etName"            android:layout_width="0dp"            android:layout_height="wrap_content"            android:layout_weight="1"            android:hint="商品名称"            android:inputType="textPersonName"/>        <EditText            android:id="@+id/etAmount"            android:layout_width="0dp"            android:layout_height="wrap_content"            android:layout_weight="1"            android:hint="商品金额"            android:inputType="number"/>        <ImageView            android:layout_width="wrap_content"            android:layout_height="wrap_content"            android:onClick="addGoods"            android:id="@+id/ivAdd"            android:src="@android:drawable/ic_input_add"/>    </LinearLayout>    <ListView        android:layout_width="match_parent"        android:layout_height="match_parent"        android:id="@+id/lvGoods"        android:layout_below="@+id/llAdd"        >    </ListView></LinearLayout>

6.item.xml

<?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"    android:orientation="horizontal"    android:padding="10dp">    <TextView        android:id="@+id/tvId"        android:layout_width="0dp"        android:layout_height="wrap_content"        android:layout_weight="1"        android:text="13"        android:textColor="#000000"        android:textSize="20sp" />    <TextView        android:id="@+id/tvName"        android:layout_width="0dp"        android:layout_height="wrap_content"        android:layout_weight="2"        android:text="商品名称"        android:gravity="left"        android:textColor="#000000"        android:textSize="20sp" />    <TextView        android:id="@+id/tvAmount"        android:layout_width="0dp"        android:layout_height="wrap_content"        android:layout_weight="2"        android:text="金额"        android:gravity="left"        android:textColor="#000000"        android:textSize="20sp" />    <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:layout_marginBottom="2dp"            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_up_float" />    </LinearLayout>    <ImageView        android:id="@+id/ivDelete"        android:layout_width="25dp"        android:layout_height="25dp"        android:src="@android:drawable/ic_menu_delete" /></LinearLayout>