Android -- carrinho de compras

Exemplo de carrinho de compras simples

Descrição da função do carrinho de compras

        Quando você entra na página do carrinho de compras pela primeira vez, o carrinho de compras está vazio e, ao mesmo tempo, você é solicitado a ir ao shopping do celular, conforme mostrado no diagrama da página da primeira entrada. Em seguida, vá para a página do shopping para comprar telefones celulares, escolha alguns telefones celulares e adicione-os ao carrinho de compras e, em seguida, retorne à página do carrinho de compras, você pode ver a lista de produtos no carrinho de compras, conforme mostrado na lista selecionada do carrinho de compras, há fotos de produtos, nomes, quantidade, preço unitário, preço total e outras informações. Obviamente, o carrinho de compras não apenas exibe os produtos a serem adquiridos, mas também suporta a operação de liquidação da compra final, suporta o esvaziamento do carrinho de compras e pressionamentos longos para excluir pedidos individuais e outras funções.

        A presença do carrinho de compras é muito forte, e o carrinho de compras só pode ser visto na página do carrinho de compras. Muitas vezes, na página do shopping, ou mesmo na página de detalhes do produto, você verá um ícone de carrinho de compras aparecendo em um canto. Depois que um novo produto é adicionado ao carrinho de compras, o número de produtos no ícone do carrinho de compras aumenta em um imediatamente. Obviamente, os usuários também podem clicar no ícone do carrinho de compras para ir diretamente para a página do carrinho de compras. Além da lista de produtos na página do shopping, há também um ícone de carrinho de compras no canto superior direito da página. Quando os usuários adicionam produtos ao carrinho de compras, o número no ícone também aumenta em um.

Requisitos funcionais

• O carrinho de compras armazena os produtos que o usuário vai comprar. No início está vazio. À medida que os produtos forem adicionados ao carrinho de compras, o carrinho de compras exibirá a lista de produtos adicionados.

• Além da página do carrinho de compras, outras páginas (como páginas do canal do shopping, páginas de detalhes do produto) podem encontrar o ícone do carrinho de compras no canto superior direito ou no canto inferior direito. A quantidade de itens adicionados será exibida no ícone do carrinho de compras e a quantidade de itens é atualizada em tempo real.

• A página do carrinho de compras, a página do canal do shopping e a página de detalhes do produto exibirão imagens pequenas ou grandes do produto

design de interface

• Layout linear LinearLayout: a interface do carrinho de compras é organizada de cima para baixo e o layout linear na direção vertical

• Gridlayout GridLayout: vitrines na página do shopping, permitindo a exibição dos produtos em linhas e colunas

• Relative Layout RelativeLayout: o ícone do carrinho de compras no canto superior direito da página e a marca numérica no canto superior direito do ícone organizam os controles de acordo com a orientação especificada

• Outros controles comuns incluem exibição de texto TextView, exibição de imagem ImageView, botão de controle de botão, etc.

tecnologia de armazenamento

• Banco de dados SQLite: O mais intuitivo é o banco de dados. A lista de produtos no carrinho de compras deve ser colocada em SQLite, e a adição, exclusão, modificação e consulta

• Memória global: O número no canto superior direito do ícone do carrinho de compras indica a quantidade de itens no carrinho de compras. Recomenda-se salvar este valor na memória global, para que não seja necessário ir ao banco de dados para realizar a operação de contagem todas as vezes.

• Arquivo do cartão de memória: o aplicativo salva as imagens do produto baixadas no cartão de memória, para que da próxima vez você possa obter as imagens do produto diretamente do cartão de memória para acelerar a navegação.

• Parâmetro compartilhado SharedPreferences: Se é a primeira vez para acessar a imagem de rede, este sinalizador é recomendado para ser colocado no parâmetro compartilhado, ele precisa ser armazenado persistentemente e há apenas uma informação de parâmetro

renderizações

O mapa de página da primeira entrada

 

Mapa da lista de exibição de produtos

lista selecionada do carrinho de compras

 Mapa da página de detalhes do celular

Pressione e segure para excluir o mapa de pedidos

foto

programa principal

ShoppingChannelActivity.java

package com.kcs.shoppingcart;

import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.GridView;
import android.widget.TextView;

import androidx.appcompat.app.AppCompatActivity;

import com.kcs.shoppingcart.adapter.GoodsAdapter;
import com.kcs.shoppingcart.datebase.ShoppingDBHelper;
import com.kcs.shoppingcart.entity.GoodsInfo;
import com.kcs.shoppingcart.utils.ToastUtil;

import java.util.List;

public class ShoppingChannelActivity extends AppCompatActivity implements View.OnClickListener, GoodsAdapter.AddCartListener {

    /**
     * 声明一个商品数据库的帮助器对象
     */
    private ShoppingDBHelper mDBHelper;
    private TextView tv_count;
    private GridView gv_channel;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_shopping_channel);
        TextView tv_title = findViewById(R.id.tv_title);
        tv_title.setText("手机商场");

        tv_count = findViewById(R.id.tv_count);
        gv_channel = findViewById(R.id.gv_channel);
        findViewById(R.id.iv_back).setOnClickListener(this);
        findViewById(R.id.iv_cart).setOnClickListener(this);

        mDBHelper = ShoppingDBHelper.getInstance(this);
        mDBHelper.openReadLink();
        mDBHelper.openWriteLink();

        // 从数据库查询出商品信息，并展示
        showGoods();
    }

    @Override
    protected void onResume() {
        super.onResume();
        // 查询购物车商品总数，并展示
        showCartInfoTotal();
    }

    /**
     * 查询购物车商品总数，并展示
     */
    private void showCartInfoTotal() {
        int count = mDBHelper.countCartInfo();
        MyApplication.getInstance().goodsCount = count;
        tv_count.setText(String.valueOf(count));
    }

    private void showGoods() {
        // 查询商品数据库中的所有商品记录
        List<GoodsInfo> list = mDBHelper.queryAllGoodsInfo();
        GoodsAdapter adapter = new GoodsAdapter(this, list,this);
        gv_channel.setAdapter(adapter);
    }

    /**
     *  把指定编号的商品添加到购物车
     * @param goodsId
     * @param goodsName
     */

    @Override
    public void addToCart(int goodsId, String goodsName) {
        // 购物车商品数量+1
        int count = ++MyApplication.getInstance().goodsCount;
        tv_count.setText(String.valueOf(count));
        mDBHelper.insertCartInfo(goodsId);
        ToastUtil.show(this, "已添加一部" + goodsName + "到购物车");
    }

    @Override
    protected void onDestroy() {
        super.onDestroy();
        mDBHelper.closeLink();
    }

    @Override
    public void onClick(View v) {
        switch (v.getId()) {
            case R.id.iv_back:
                // 点击了返回图标，关闭当前页面
                finish();
                break;
            case R.id.iv_cart:
                // 点击了购物车图标
                // 从商场页面跳到购物车页面
                Intent intent = new Intent(this, ShoppingCartActivity.class);
                // 设置启动标志，避免多次返回同一页面的
                intent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
                startActivity(intent);
                break;
            default:
                break;
        }
    }
}

ShoppingDetailActivity.java

import androidx.appcompat.app.AppCompatActivity;

import android.content.Intent;
import android.net.Uri;
import android.os.Bundle;
import android.view.View;
import android.widget.ImageView;
import android.widget.TextView;

import com.dongnaoedu.chapter06.database.ShoppingDBHelper;
import com.dongnaoedu.chapter06.enity.GoodsInfo;
import com.dongnaoedu.chapter06.util.ToastUtil;

public class ShoppingDetailActivity extends AppCompatActivity implements View.OnClickListener {

    private TextView tv_title;
    private TextView tv_count;
    private TextView tv_goods_price;
    private TextView tv_goods_desc;
    private ImageView iv_goods_pic;
    private ShoppingDBHelper mDBHelper;
    private int mGoodsId;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_shopping_detail);
        tv_title = findViewById(R.id.tv_title);
        tv_count = findViewById(R.id.tv_count);
        tv_goods_price = findViewById(R.id.tv_goods_price);
        tv_goods_desc = findViewById(R.id.tv_goods_desc);
        iv_goods_pic = findViewById(R.id.iv_goods_pic);
        findViewById(R.id.iv_back).setOnClickListener(this);
        findViewById(R.id.iv_cart).setOnClickListener(this);
        findViewById(R.id.btn_add_cart).setOnClickListener(this);

        tv_count.setText(String.valueOf(MyApplication.getInstance().goodsCount));

        mDBHelper = ShoppingDBHelper.getInstance(this);

    }

    @Override
    protected void onResume() {
        super.onResume();
        showDetail();
    }

    private void showDetail() {
        // 获取上一个页面传来的商品编号
        mGoodsId = getIntent().getIntExtra("goods_id", 0);
        if (mGoodsId > 0) {
            // 根据商品编号查询商品数据库中的商品记录
            GoodsInfo info = mDBHelper.queryGoodsInfoById(mGoodsId);
            tv_title.setText(info.name);
            tv_goods_desc.setText(info.description);
            tv_goods_price.setText(String.valueOf((int) info.price));
            iv_goods_pic.setImageURI(Uri.parse(info.picPath));
        }
    }

    @Override
    public void onClick(View v) {
        switch (v.getId()) {
            case R.id.iv_back:
                finish();
                break;

            case R.id.iv_cart:
                Intent intent = new Intent(this, ShoppingCartActivity.class);
                startActivity(intent);
                break;

            case R.id.btn_add_cart:
                addToCart(mGoodsId);
                break;
        }
    }

    private void addToCart(int goodsId) {
        // 购物车商品数量+1
        int count = ++MyApplication.getInstance().goodsCount;
        tv_count.setText(String.valueOf(count));
        mDBHelper.insertCartInfo(goodsId);
        ToastUtil.show(this, "成功添加至购物车");
    }
}

ShoppingCartActivity.java

package com.kcs.shoppingcart;

import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.AdapterView;
import android.widget.LinearLayout;
import android.widget.ListView;
import android.widget.TextView;

import androidx.appcompat.app.AlertDialog;
import androidx.appcompat.app.AppCompatActivity;

import com.kcs.shoppingcart.adapter.CartAdapter;
import com.kcs.shoppingcart.datebase.ShoppingDBHelper;
import com.kcs.shoppingcart.entity.CartInfo;
import com.kcs.shoppingcart.entity.GoodsInfo;
import com.kcs.shoppingcart.utils.ToastUtil;

import java.util.HashMap;
import java.util.List;
import java.util.Map;

public class ShoppingCartActivity extends AppCompatActivity implements View.OnClickListener, AdapterView.OnItemClickListener, AdapterView.OnItemLongClickListener {

    private TextView tv_count;
    private ListView lv_cart;
    private ShoppingDBHelper mDBHelper;

    /**
     * 声明一个购物车中的商品信息列表
     */
    private List<CartInfo> mCartList;
    /**
     * 声明一个根据商品编号查找商品信息的映射，把商品信息缓存起来，这样不用每一次都去查询数据库
     */
    private Map<Integer, GoodsInfo> mGoodsMap = new HashMap<>();
    private TextView tv_total_price;
    private LinearLayout ll_empty;
    private LinearLayout ll_content;
    private CartAdapter mCartAdapter;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_shopping_cart);
        TextView tv_title = findViewById(R.id.tv_title);
        tv_title.setText("购物车");
        lv_cart = findViewById(R.id.lv_cart);
        tv_total_price = findViewById(R.id.tv_total_price);

        tv_count = findViewById(R.id.tv_count);
        tv_count.setText(String.valueOf(MyApplication.getInstance().goodsCount));

        mDBHelper = ShoppingDBHelper.getInstance(this);

        findViewById(R.id.iv_back).setOnClickListener(this);
        findViewById(R.id.btn_shopping_channel).setOnClickListener(this);
        findViewById(R.id.btn_clear).setOnClickListener(this);
        findViewById(R.id.btn_settle).setOnClickListener(this);
        ll_empty = findViewById(R.id.ll_empty);
        ll_content = findViewById(R.id.ll_content);
    }

    @Override
    protected void onResume() {
        super.onResume();
        showCart();
    }

    /**
     * 展示购物车中的商品列表
     */
    private void showCart() {
        // 查询购物车数据库中所有的商品记录
        mCartList = mDBHelper.queryAllCartInfo();
        if (mCartList.size() == 0) {
            return;
        }
        for (CartInfo info : mCartList) {
            // 根据商品编号查询商品数据库中的商品记录
            GoodsInfo goods = mDBHelper.queryGoodsInfoById(info.goodsId);
            mGoodsMap.put(info.goodsId, goods);
            info.goods = goods;
        }
        mCartAdapter = new CartAdapter(this, mCartList);
        lv_cart.setAdapter(mCartAdapter);
        // 给商品行添加点击事件。点击商品行跳到商品的详情页
        lv_cart.setOnItemClickListener(this);
        // 给商品行添加长按事件。长按商品行就删除该商品
        lv_cart.setOnItemLongClickListener(this);

        // 重新计算购物车中的商品总金额
        refreshTotalPrice();
    }

    private void deleteGoods(CartInfo info) {
        MyApplication.getInstance().goodsCount -= info.count;
        // 从购物车的数据库中删除商品
        mDBHelper.deleteCartInfoByGoodsId(info.goodsId);
        // 从购物车的列表中删除商品
        CartInfo removed = null;
        for (CartInfo cartInfo : mCartList) {
            if (cartInfo.goodsId == info.goodsId) {
                removed = cartInfo;
                break;
            }
        }
        mCartList.remove(removed);
        // 显示最新的商品数量
        showCount();
        ToastUtil.show(this, "已从购物车删除" + mGoodsMap.get(info.goodsId).name);
        mGoodsMap.remove(info.goodsId);
        // 刷新购物车中所有商品的总金额
        refreshTotalPrice();
    }

    /**
     * 显示购物车图标中的商品数量
     */
    private void showCount() {
        tv_count.setText(String.valueOf(MyApplication.getInstance().goodsCount));
        // 购物车中没有商品，显示“空空如也”
        if (MyApplication.getInstance().goodsCount == 0) {
            ll_empty.setVisibility(View.VISIBLE);
            ll_content.setVisibility(View.GONE);
            // 通知适配器发生了数据变化
            mCartAdapter.notifyDataSetChanged();
        } else {
            ll_content.setVisibility(View.VISIBLE);
            ll_empty.setVisibility(View.GONE);
        }
    }

    /**
     * 重新计算购物车中的商品总金额
     */
    private void refreshTotalPrice() {
        int totalPrice = 0;
        for (CartInfo info : mCartList) {
            GoodsInfo goods = mGoodsMap.get(info.goodsId);
            totalPrice += goods.price * info.count;
        }
        tv_total_price.setText(String.valueOf(totalPrice));
    }

    @Override
    public void onClick(View v) {
        switch (v.getId()) {
            case R.id.iv_back:
                // 点击了返回图标
                // 关闭当前页面
                finish();
                break;

            case R.id.btn_shopping_channel:
                // 从购物车页面跳到商场页面
                Intent intent = new Intent(this, com.kcs.shoppingcart.ShoppingChannelActivity.class);
                intent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
                startActivity(intent);
                break;

            case R.id.btn_clear:
                // 清空购物车数据库
                mDBHelper.deleteAllCartInfo();
                MyApplication.getInstance().goodsCount = 0;
                // 显示最新的商品数量
                showCount();
                ToastUtil.show(this, "购物车已清空");
                break;

            case R.id.btn_settle:
                // 点击了“结算”按钮
                AlertDialog.Builder builder = new AlertDialog.Builder(this);
                builder.setTitle("结算商品");
                builder.setMessage("客官抱歉，支付功能尚未开通");
                builder.setPositiveButton("我知道了", null);
                builder.create().show();
                break;
            default:
                break;
        }
    }

    /**
     * 给商品行添加点击事件。点击商品行跳到商品的详情页
     */
    @Override
    public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
        Intent intent = new Intent(ShoppingCartActivity.this, com.kcs.shoppingcart.ShoppingDetailActivity.class);
        intent.putExtra("goods_id", mCartList.get(position).goodsId);
        startActivity(intent);
    }

    /**
     *给商品行添加长按事件。长按商品行就删除该商品
     */
    @Override
    public boolean onItemLongClick(AdapterView<?> parent, View view, int position, long id) {
        CartInfo info = mCartList.get(position);
        AlertDialog.Builder builder = new AlertDialog.Builder(ShoppingCartActivity.this);
        builder.setMessage("是否从购物车删除" + info.goods.name + "？");
        builder.setPositiveButton("是", (dialog, which) -> {
            // 从集合中移除数据
            mCartList.remove(position);
            // 通知适配器发生了数据变化
            mCartAdapter.notifyDataSetChanged();
            // 删除该商品
            deleteGoods(info);
        });
        builder.setNegativeButton("否", null);
        builder.create().show();
        return true;
    }
}

MeuAplicativo.java

package com.dongnaoedu.chapter06;

import android.app.Application;
import android.content.res.Configuration;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.os.Environment;
import android.util.Log;


import androidx.annotation.NonNull;
import androidx.room.Room;

import com.dongnaoedu.chapter06.database.ShoppingDBHelper;
import com.dongnaoedu.chapter06.enity.GoodsInfo;
import com.dongnaoedu.chapter06.util.FileUtil;
import com.dongnaoedu.chapter06.util.SharedUtil;

import java.io.File;
import java.util.HashMap;
import java.util.List;

public class MyApplication extends Application {

    // 购物车中的商品总数量
    public int goodsCount;

    public static MyApplication getInstance() {
        return mApp;
    }


    //在App启动时调用
    @Override
    public void onCreate() {
        super.onCreate();
        mApp = this;
        Log.d("ning", "MyApplication onCreate");

        // 初始化商品信息
        initGoodsInfo();
    }

    private void initGoodsInfo() {
        // 获取共享参数保存的是否首次打开参数
        boolean isFirst = SharedUtil.getInstance(this).readBoolean("first", true);
        // 获取当前App的私有下载路径
        String directory = getExternalFilesDir(Environment.DIRECTORY_DOWNLOADS).toString() + File.separatorChar;
        if (isFirst) {
            // 模拟网络图片下载
            List<GoodsInfo> list = GoodsInfo.getDefaultList();
            for (GoodsInfo info : list) {
                Bitmap bitmap = BitmapFactory.decodeResource(getResources(), info.pic);
                String path = directory + info.id + ".jpg";
                // 往存储卡保存商品图片
                FileUtil.saveImage(path, bitmap);
                // 回收位图对象
                bitmap.recycle();
                info.picPath = path;
            }
            // 打开数据库，把商品信息插入到表中
            ShoppingDBHelper dbHelper = ShoppingDBHelper.getInstance(this);
            dbHelper.openWriteLink();
            dbHelper.insertGoodsInfos(list);
            dbHelper.closeLink();
            // 把是否首次打开写入共享参数
            SharedUtil.getInstance(this).writeBoolean("first", false);
        }
    }

}

adaptador

 pacote: adaptador

CartAdapter.java

package com.kcs.shoppingcart.adapter;

import android.content.Context;
import android.net.Uri;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.ImageView;
import android.widget.TextView;


import com.kcs.shoppingcart.R;
import com.kcs.shoppingcart.entity.CartInfo;

import java.util.List;

public class CartAdapter extends BaseAdapter {

    private Context mContext;
    private List<CartInfo> mCartList;

    public CartAdapter(Context mContext, List<CartInfo> mCartList) {
        this.mContext = mContext;
        this.mCartList = mCartList;
    }

    @Override
    public int getCount() {
        return mCartList.size();
    }

    @Override
    public Object getItem(int position) {
        return mCartList.get(position);
    }

    @Override
    public long getItemId(int position) {
        return position;
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        ViewHolder holder;
        if (convertView == null) {
            holder = new ViewHolder();
            // 获取布局文件item_cart.xml的根视图
            convertView = LayoutInflater.from(mContext).inflate(R.layout.item_cart, null);
            holder.iv_thumb = convertView.findViewById(R.id.iv_thumb);
            holder.tv_name = convertView.findViewById(R.id.tv_name);
            holder.tv_desc = convertView.findViewById(R.id.tv_desc);
            holder.tv_count = convertView.findViewById(R.id.tv_count);
            holder.tv_price = convertView.findViewById(R.id.tv_price);
            holder.tv_sum = convertView.findViewById(R.id.tv_sum);
            convertView.setTag(holder);
        } else {
            holder = (ViewHolder) convertView.getTag();
        }

        CartInfo info = mCartList.get(position);
        holder.iv_thumb.setImageURI(Uri.parse(info.goods.picPath));
        holder.tv_name.setText(info.goods.name);
        holder.tv_desc.setText(info.goods.description);
        holder.tv_count.setText(String.valueOf(info.count));
        holder.tv_price.setText(String.valueOf((int) info.goods.price));
        // 设置商品总价
        holder.tv_sum.setText(String.valueOf((int) (info.count * info.goods.price)));
        return convertView;
    }

    public final class ViewHolder {
        public ImageView iv_thumb;
        public TextView tv_name;
        public TextView tv_desc;
        public TextView tv_count;
        public TextView tv_price;
        public TextView tv_sum;

    }
}

GoodsAdapter.java

package com.kcs.shoppingcart.adapter;

import android.content.Context;
import android.content.Intent;
import android.net.Uri;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.TextView;

import com.kcs.shoppingcart.R;
import com.kcs.shoppingcart.ShoppingDetailActivity;
import com.kcs.shoppingcart.entity.GoodsInfo;

import java.util.List;

public class GoodsAdapter extends BaseAdapter {

    private Context mContext;
    private List<GoodsInfo> mGoodsInfo;

    public GoodsAdapter(Context mContext, List<GoodsInfo> mGoodsInfo, AddCartListener mAddCartListener) {
        this.mContext = mContext;
        this.mGoodsInfo = mGoodsInfo;
        this.mAddCartListener = mAddCartListener;
    }

    @Override
    public int getCount() {
        return mGoodsInfo.size();
    }

    @Override
    public Object getItem(int position) {
        return position;
    }

    @Override
    public long getItemId(int position) {
        return position;
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        GoodsInfo info = mGoodsInfo.get(position);
        ViewHolder holder;
        if (convertView == null) {
            convertView = LayoutInflater.from(mContext).inflate(R.layout.item_goods, null);
            holder = new ViewHolder();
            holder.iv_thumb = convertView.findViewById(R.id.iv_thumb);
            holder.tv_name = convertView.findViewById(R.id.tv_name);
            holder.tv_price = convertView.findViewById(R.id.tv_price);
            holder.btn_add = convertView.findViewById(R.id.btn_add);
            convertView.setTag(holder);
        } else {
            holder = (ViewHolder) convertView.getTag();
        }


        // 给控件设置值
        holder.iv_thumb.setImageURI(Uri.parse(info.picPath));
        holder.tv_name.setText(info.name);
        holder.tv_price.setText(String.valueOf((int) info.price));

        // 添加到购物车
        holder.btn_add.setOnClickListener(v -> {
            mAddCartListener.addToCart(info.id, info.name);
        });

        //点击商品图片，跳转到商品详情页面

        holder.iv_thumb.setOnClickListener(v -> {
            Intent intent = new Intent(mContext, ShoppingDetailActivity.class);
            intent.putExtra("goods_id", info.id);
            mContext.startActivity(intent);
        });

        return convertView;
    }

    public final class ViewHolder {
        public ImageView iv_thumb;
        public TextView tv_name;
        public TextView tv_price;
        public Button btn_add;
    }

    /**
     * 声明一个加入购物车的监听器对象
     */
    private AddCartListener mAddCartListener;

    /**
     * 定义一个加入购物车的监听器接口
     */
    public interface AddCartListener {
        void addToCart(int goodsId, String goodsName);
    }
}

Ferramentas

utilidade do pacote:

ToastUitl.java

package com.dongnaoedu.chapter06.util;

import android.content.Context;
import android.widget.Toast;

public class ToastUtil {

    public static void show(Context ctx, String desc) {
        Toast.makeText(ctx, desc, Toast.LENGTH_SHORT).show();
    }

}

SharedUtil.java

import android.content.Context;
import android.content.SharedPreferences;

public class SharedUtil {

    private static SharedUtil mUtil;
    private SharedPreferences preferences;

    public static SharedUtil getInstance(Context ctx) {
        if (mUtil == null) {
            mUtil = new SharedUtil();
            mUtil.preferences = ctx.getSharedPreferences("shopping", Context.MODE_PRIVATE);
        }
        return mUtil;
    }

    public void writeBoolean(String key, boolean value) {
        SharedPreferences.Editor editor = preferences.edit();
        editor.putBoolean(key, value);
        editor.commit();
    }

    public boolean readBoolean(String key, boolean defaultValue) {
        return preferences.getBoolean(key, defaultValue);
    }

}

FileUtil.java

import android.graphics.Bitmap;
import android.graphics.BitmapFactory;

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;

public class FileUtil {

    // 把位图数据保存到指定路径的图片文件
    public static void saveImage(String path, Bitmap bitmap) {
        FileOutputStream fos = null;
        try {
            fos = new FileOutputStream(path);
            // 把位图数据压缩到文件输出流中
            bitmap.compress(Bitmap.CompressFormat.JPEG, 100, fos);
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            if (fos != null) {
                try {
                    fos.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
    }

    // 从指定路径的图片文件中读取位图数据
    public static Bitmap openImage(String path) {
        Bitmap bitmap = null;
        FileInputStream fis = null;
        try {
            fis = new FileInputStream(path);
            bitmap = BitmapFactory.decodeStream(fis);
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            if (fis != null) {
                try {
                    fis.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
        return bitmap;
    }
}

Classe de entidade 

pacote pojos:

CarInfo.java

package com.kcs.shoppingcart.entity;

//购物车信息
public class CartInfo {
    public int id;
    /**
     * 商品编号
     */
    public int goodsId;
    /**
     * 商品数量
     */
    public int count;
    /**
     * 商品信息
     */
    public GoodsInfo goods;

    public CartInfo() {
    }

    public CartInfo(int id, int goodsId, int count) {
        this.id = id;
        this.goodsId = goodsId;
        this.count = count;
        this.goods = new GoodsInfo();
    }
}

GoodsInfo.java

import com.dongnaoedu.chapter06.R;

import java.util.ArrayList;

public class GoodsInfo {

    public int id;
    // 名称
    public String name;
    // 描述
    public String description;
    // 价格
    public float price;
    // 大图的保存路径
    public String picPath;
    // 大图的资源编号
    public int pic;

    // 声明一个手机商品的名称数组
    private static String[] mNameArray = {
            "iPhone11", "Mate30", "小米10", "OPPO Reno3", "vivo X30", "荣耀30S"
    };
    // 声明一个手机商品的描述数组
    private static String[] mDescArray = {
            "Apple iPhone11 256GB 绿色 4G全网通手机",
            "华为 HUAWEI Mate30 8GB+256GB 丹霞橙 5G全网通 全面屏手机",
            "小米 MI10 8GB+128GB 钛银黑 5G手机 游戏拍照手机",
            "OPPO Reno3 8GB+128GB 蓝色星夜 双模5G 拍照游戏智能手机",
            "vivo X30 8GB+128GB 绯云 5G全网通 美颜拍照手机",
            "荣耀30S 8GB+128GB 蝶羽红 5G芯片 自拍全面屏手机"
    };
    // 声明一个手机商品的价格数组
    private static float[] mPriceArray = {6299, 4999, 3999, 2999, 2998, 2399};
    // 声明一个手机商品的大图数组
    private static int[] mPicArray = {
            R.drawable.iphone, R.drawable.huawei, R.drawable.xiaomi,
            R.drawable.oppo, R.drawable.vivo, R.drawable.rongyao
    };

    // 获取默认的手机信息列表
    public static ArrayList<GoodsInfo> getDefaultList() {
        ArrayList<GoodsInfo> goodsList = new ArrayList<GoodsInfo>();
        for (int i = 0; i < mNameArray.length; i++) {
            GoodsInfo info = new GoodsInfo();
            info.id = i;
            info.name = mNameArray[i];
            info.description = mDescArray[i];
            info.price = mPriceArray[i];
            info.pic = mPicArray[i];
            goodsList.add(info);
        }
        return goodsList;
    }
}

Classe do banco de dados do carrinho de compras

banco de dados de pacotes:

import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;

import com.dongnaoedu.chapter06.enity.CartInfo;
import com.dongnaoedu.chapter06.enity.GoodsInfo;

import java.util.ArrayList;
import java.util.List;

public class ShoppingDBHelper extends SQLiteOpenHelper {

    private static final String DB_NAME = "shopping.db";
    // 商品信息表
    private static final String TABLE_GOODS_INFO = "goods_info";
    // 购物车信息表
    private static final String TABLE_CART_INFO = "cart_info";
    private static final int DB_VERSION = 1;
    private static ShoppingDBHelper mHelper = null;
    private SQLiteDatabase mRDB = null;
    private SQLiteDatabase mWDB = null;

    private ShoppingDBHelper(Context context) {
        super(context, DB_NAME, null, DB_VERSION);
    }

    // 利用单例模式获取数据库帮助器的唯一实例
    public static ShoppingDBHelper getInstance(Context context) {
        if (mHelper == null) {
            mHelper = new ShoppingDBHelper(context);
        }
        return mHelper;
    }

    // 打开数据库的读连接
    public SQLiteDatabase openReadLink() {
        if (mRDB == null || !mRDB.isOpen()) {
            mRDB = mHelper.getReadableDatabase();
        }
        return mRDB;
    }

    // 打开数据库的写连接
    public SQLiteDatabase openWriteLink() {
        if (mWDB == null || !mWDB.isOpen()) {
            mWDB = mHelper.getWritableDatabase();
        }
        return mWDB;
    }

    // 关闭数据库连接
    public void closeLink() {
        if (mRDB != null && mRDB.isOpen()) {
            mRDB.close();
            mRDB = null;
        }

        if (mWDB != null && mWDB.isOpen()) {
            mWDB.close();
            mWDB = null;
        }
    }

    // 创建数据库，执行建表语句
    @Override
    public void onCreate(SQLiteDatabase db) {
        // 创建商品信息表
        String sql = "CREATE TABLE IF NOT EXISTS " + TABLE_GOODS_INFO +
                "(_id INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL," +
                " name VARCHAR NOT NULL," +
                " description VARCHAR NOT NULL," +
                " price FLOAT NOT NULL," +
                " pic_path VARCHAR NOT NULL);";
        db.execSQL(sql);

        // 创建购物车信息表
        sql = "CREATE TABLE IF NOT EXISTS " + TABLE_CART_INFO +
                "(_id INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL," +
                " goods_id INTEGER NOT NULL," +
                " count INTEGER NOT NULL);";
        db.execSQL(sql);
    }

    @Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {

    }

    // 添加多条商品信息
    public void insertGoodsInfos(List<GoodsInfo> list) {
        // 插入多条记录，要么全部成功，要么全部失败
        try {
            mWDB.beginTransaction();
            for (GoodsInfo info : list) {
                ContentValues values = new ContentValues();
                values.put("name", info.name);
                values.put("description", info.description);
                values.put("price", info.price);
                values.put("pic_path", info.picPath);
                mWDB.insert(TABLE_GOODS_INFO, null, values);
            }
            mWDB.setTransactionSuccessful();
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            mWDB.endTransaction();
        }
    }

    // 查询所有的商品信息
    public List<GoodsInfo> queryAllGoodsInfo() {
        String sql = "select * from " + TABLE_GOODS_INFO;
        List<GoodsInfo> list = new ArrayList<>();
        Cursor cursor = mRDB.rawQuery(sql, null);
        while (cursor.moveToNext()) {
            GoodsInfo info = new GoodsInfo();
            info.id = cursor.getInt(0);
            info.name = cursor.getString(1);
            info.description = cursor.getString(2);
            info.price = cursor.getFloat(3);
            info.picPath = cursor.getString(4);
            list.add(info);
        }
        cursor.close();
        return list;
    }

    // 添加商品到购物车
    public void insertCartInfo(int goodsId) {
        // 如果购物车中不存在该商品，添加一条信息
        CartInfo cartInfo = queryCartInfoByGoodsId(goodsId);
        ContentValues values = new ContentValues();
        values.put("goods_id", goodsId);
        if (cartInfo == null) {
            values.put("count", 1);
            mWDB.insert(TABLE_CART_INFO, null, values);
        } else {
            // 如果购物车中已经存在该商品，更新商品数量
            values.put("_id", cartInfo.id);
            values.put("count", ++cartInfo.count);
            mWDB.update(TABLE_CART_INFO, values, "_id=?", new String[]{String.valueOf(cartInfo.id)});
        }
    }

    // 根据商品信息ID查询购物车信息
    private CartInfo queryCartInfoByGoodsId(int goodsId) {
        Cursor cursor = mRDB.query(TABLE_CART_INFO, null, "goods_id=?", new String[]{String.valueOf(goodsId)}, null, null, null);
        CartInfo info = null;
        if (cursor.moveToNext()) {
            info = new CartInfo();
            info.id = cursor.getInt(0);
            info.goodsId = cursor.getInt(1);
            info.count = cursor.getInt(2);
        }
        return info;
    }

    // 统计购物车中商品的总数量
    public int countCartInfo() {
        int count = 0;
        String sql = "select sum(count) from " + TABLE_CART_INFO;
        Cursor cursor = mRDB.rawQuery(sql, null);
        if (cursor.moveToNext()) {
            count = cursor.getInt(0);
        }
        return count;
    }

    // 查询购物车中所有的信息列表
    public List<CartInfo> queryAllCartInfo() {
        List<CartInfo> list = new ArrayList<>();
        Cursor cursor = mRDB.query(TABLE_CART_INFO, null, null, null, null, null, null);
        while (cursor.moveToNext()) {
            CartInfo info = new CartInfo();
            info.id = cursor.getInt(0);
            info.goodsId = cursor.getInt(1);
            info.count = cursor.getInt(2);
            list.add(info);
        }
        return list;
    }

    // 根据商品ID查询商品信息
    public GoodsInfo queryGoodsInfoById(int goodsId) {
        GoodsInfo info = null;
        Cursor cursor = mRDB.query(TABLE_GOODS_INFO, null, "_id=?", new String[]{String.valueOf(goodsId)}, null, null, null);
        if (cursor.moveToNext()) {
            info = new GoodsInfo();
            info.id = cursor.getInt(0);
            info.name = cursor.getString(1);
            info.description = cursor.getString(2);
            info.price = cursor.getFloat(3);
            info.picPath = cursor.getString(4);
        }
        return info;
    }

    // 根据商品ID删除购物车信息
    public void deleteCartInfoByGoodsId(int goodsId) {
        mWDB.delete(TABLE_CART_INFO, "goods_id=?", new String[]{String.valueOf(goodsId)});
    }

    // 删除所有购物车信息
    public void deleteAllCartInfo() {
        mWDB.delete(TABLE_CART_INFO, "1=1", null);
    }
}

arquivo de layout

activity_shopping_channel.xml

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="@color/orange"
    android:orientation="vertical" >

    <include layout="@layout/title_shopping" />

    <GridView
        android:id="@+id/gv_channel"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:numColumns="2" />

</LinearLayout>

activity_shopping_detail.xml

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="@color/orange"
    android:orientation="vertical">

    <include layout="@layout/title_shopping" />

    <ScrollView
        android:layout_width="match_parent"
        android:layout_height="wrap_content">

        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:orientation="vertical">

            <ImageView
                android:id="@+id/iv_goods_pic"
                android:layout_width="match_parent"
                android:layout_height="350dp"
                android:scaleType="fitCenter"
                tools:src="@drawable/xiaomi" />

            <TextView
                android:id="@+id/tv_goods_price"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:paddingLeft="5dp"
                android:textColor="@color/red"
                android:textSize="22sp"
                tools:text="1990" />

            <TextView
                android:id="@+id/tv_goods_desc"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:paddingLeft="5dp"
                android:textColor="@color/black"
                android:textSize="15sp"
                tools:text="小米 MI10 8GB+128GB 钛银黑 5G手机 游戏拍照手机" />

            <Button
                android:id="@+id/btn_add_cart"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:text="加入购物车"
                android:textColor="@color/black"
                android:textSize="17sp" />
        </LinearLayout>
    </ScrollView>

</LinearLayout>

activity_shopping_car.xml

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="@color/orange"
    android:orientation="vertical">

    <include layout="@layout/title_shopping" />

    <ScrollView
        android:layout_width="match_parent"
        android:layout_height="wrap_content">

        <RelativeLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content">

            <LinearLayout
                android:id="@+id/ll_content"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:orientation="vertical"
                android:visibility="visible">

                <LinearLayout
                    android:layout_width="match_parent"
                    android:layout_height="wrap_content"
                    android:orientation="horizontal">

                    <TextView
                        android:layout_width="85dp"
                        android:layout_height="wrap_content"
                        android:gravity="center"
                        android:text="图片"
                        android:textColor="@color/black"
                        android:textSize="15sp" />

                    <TextView
                        android:layout_width="0dp"
                        android:layout_height="wrap_content"
                        android:layout_weight="3"
                        android:gravity="center"
                        android:text="名称"
                        android:textColor="@color/black"
                        android:textSize="15sp" />

                    <TextView
                        android:layout_width="0dp"
                        android:layout_height="wrap_content"
                        android:layout_weight="1"
                        android:gravity="center"
                        android:text="数量"
                        android:textColor="@color/black"
                        android:textSize="15sp" />

                    <TextView
                        android:layout_width="0dp"
                        android:layout_height="wrap_content"
                        android:layout_weight="1"
                        android:gravity="center"
                        android:text="单价"
                        android:textColor="@color/black"
                        android:textSize="15sp" />

                    <TextView
                        android:layout_width="0dp"
                        android:layout_height="wrap_content"
                        android:layout_weight="1"
                        android:gravity="center"
                        android:text="总价"
                        android:textColor="@color/black"
                        android:textSize="15sp" />

                </LinearLayout>

                <LinearLayout
                    android:id="@+id/ll_cart"
                    android:layout_width="match_parent"
                    android:layout_height="wrap_content"
                    android:orientation="vertical" />

                <LinearLayout
                    android:layout_width="match_parent"
                    android:layout_height="wrap_content"
                    android:orientation="horizontal"
                    android:padding="0dp">

                    <Button
                        android:id="@+id/btn_clear"
                        android:layout_width="wrap_content"
                        android:layout_height="wrap_content"
                        android:gravity="center"
                        android:text="清空"
                        android:textColor="@color/black"
                        android:textSize="17sp" />

                    <TextView
                        android:layout_width="0dp"
                        android:layout_height="wrap_content"
                        android:layout_weight="1"
                        android:gravity="center|right"
                        android:text="总金额："
                        android:textColor="@color/black"
                        android:textSize="17sp" />

                    <TextView
                        android:id="@+id/tv_total_price"
                        android:layout_width="wrap_content"
                        android:layout_height="wrap_content"
                        android:layout_marginRight="10dp"
                        android:gravity="center|left"
                        android:textColor="@color/red"
                        android:textSize="25sp" />

                    <Button
                        android:id="@+id/btn_settle"
                        android:layout_width="wrap_content"
                        android:layout_height="wrap_content"
                        android:gravity="center"
                        android:text="结算"
                        android:textColor="@color/black"
                        android:textSize="17sp" />
                </LinearLayout>

            </LinearLayout>

            <LinearLayout
                android:id="@+id/ll_empty"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:orientation="vertical"
                android:visibility="gone"
                tools:visibility="visible">

                <TextView
                    android:layout_width="match_parent"
                    android:layout_height="wrap_content"
                    android:layout_marginTop="100dp"
                    android:layout_marginBottom="100dp"
                    android:gravity="center"
                    android:text="哎呀，购物车空空如也，快去选购商品吧"
                    android:textColor="@color/black"
                    android:textSize="17sp" />

                <Button
                    android:id="@+id/btn_shopping_channel"
                    android:layout_width="match_parent"
                    android:layout_height="wrap_content"
                    android:gravity="center"
                    android:text="逛逛手机商场"
                    android:textColor="@color/black"
                    android:textSize="17sp" />
            </LinearLayout>
        </RelativeLayout>
    </ScrollView>

</LinearLayout>

lista de lista de carrinho de compras

item_cart.xml

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:background="@color/white"
    android:orientation="horizontal">

    <ImageView
        android:id="@+id/iv_thumb"
        android:layout_width="85dp"
        android:layout_height="85dp"
        android:scaleType="fitCenter"
        tools:src="@drawable/xiaomi"/>

    <LinearLayout
        android:layout_width="0dp"
        android:layout_height="match_parent"
        android:layout_weight="3"
        android:orientation="vertical">

        <TextView
            android:id="@+id/tv_name"
            android:layout_width="match_parent"
            android:layout_height="0dp"
            android:layout_weight="2"
            android:gravity="left|center"
            android:textColor="@color/black"
            android:textSize="17sp"
            tools:text="小米手机"/>

        <TextView
            android:id="@+id/tv_desc"
            android:layout_width="match_parent"
            android:layout_height="0dp"
            android:layout_weight="3"
            android:gravity="left|center"
            android:textColor="@color/black"
            android:textSize="12sp"
            tools:text="小米 MI10 8GB+128GB 钛银黑 5G手机 游戏拍照手机"/>
    </LinearLayout>

    <TextView
        android:id="@+id/tv_count"
        android:layout_width="0dp"
        android:layout_height="match_parent"
        android:layout_weight="1"
        android:gravity="center"
        android:textColor="@color/black"
        android:textSize="17sp"
        tools:text="2"/>

    <TextView
        android:id="@+id/tv_price"
        android:layout_width="0dp"
        android:layout_height="match_parent"
        android:layout_weight="1"
        android:gravity="right|center"
        android:textColor="@color/black"
        android:textSize="15sp"
        tools:text="1000"/>

    <TextView
        android:id="@+id/tv_sum"
        android:layout_width="0dp"
        android:layout_height="match_parent"
        android:layout_weight="1.2"
        android:gravity="right|center"
        android:textColor="@color/red"
        android:textSize="17sp"
        tools:text="2000"/>

</LinearLayout>

Arquivo de layout de dados da lista de carga

item_goods.xml

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/ll_item"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_gravity="center"
    android:background="@color/white"
    android:gravity="center"
    android:orientation="vertical">

    <TextView
        android:id="@+id/tv_name"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:gravity="center"
        android:textColor="@color/black"
        android:textSize="17sp"
        tools:text="小米手机" />

    <ImageView
        android:id="@+id/iv_thumb"
        android:layout_width="180dp"
        android:layout_height="150dp"
        android:scaleType="fitCenter"
        tools:src="@drawable/xiaomi" />

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="45dp"
        android:orientation="horizontal">

        <TextView
            android:id="@+id/tv_price"
            android:layout_width="0dp"
            android:layout_height="match_parent"
            android:layout_weight="2"
            android:gravity="center"
            android:textColor="@color/red"
            android:textSize="15sp"
            tools:text="20" />

        <Button
            android:id="@+id/btn_add"
            android:layout_width="0dp"
            android:layout_height="match_parent"
            android:layout_weight="3"
            android:gravity="center"
            android:text="加入购物车"
            android:textColor="@color/black"
            android:textSize="15sp" />
    </LinearLayout>

</LinearLayout>

arquivo de layout superior

title_shopping.xml

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="50dp"
    android:background="#aaaaff" >
    
    <ImageView
        android:id="@+id/iv_back"
        android:layout_width="50dp"
        android:layout_height="match_parent"
        android:layout_alignParentLeft="true"
        android:padding="10dp"
        android:scaleType="fitCenter"
        android:src="@drawable/ic_back" />

    <TextView
        android:id="@+id/tv_title"
        android:layout_width="wrap_content"
        android:layout_height="match_parent"
        android:layout_centerInParent="true"
        android:gravity="center"
        android:textColor="@color/black"
        android:textSize="20sp" />
    
    <ImageView
        android:id="@+id/iv_cart"
        android:layout_width="50dp"
        android:layout_height="match_parent"
        android:layout_alignParentRight="true"
        android:scaleType="fitCenter"
        android:src="@drawable/cart" />
    
    <TextView
        android:id="@+id/tv_count"
        android:layout_width="20dp"
        android:layout_height="20dp"
        android:layout_alignParentTop="true"
        android:layout_toRightOf="@+id/iv_cart"
        android:layout_marginLeft="-20dp"
        android:gravity="center"
        android:background="@drawable/shape_oval_red"
        android:text="0"
        android:textColor="@color/white"
        android:textSize="15sp" />
    
</RelativeLayout>

recurso

shape_oval_red.xml

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
    android:shape="oval">

    <solid android:color="#ff6666" />

</shape>

cores.xml

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <color name="purple_200">#FFBB86FC</color>
    <color name="purple_500">#FF6200EE</color>
    <color name="purple_700">#FF3700B3</color>
    <color name="teal_200">#FF03DAC5</color>
    <color name="teal_700">#FF018786</color>
    <color name="black">#FF000000</color>
    <color name="white">#FFFFFFFF</color>
    <color name="grey">#cccccc</color>
    <color name="orange">#ffffdd</color>
    <color name="red">#ff0000</color>
</resources>

AndroidManifest.xml

Configurar MyApplication escrito por você mesmo 

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.kcs.shoppingcart">

    <application
        android:name=".MyApplication"
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="@style/Theme.ShoppingCart">

        <activity
            android:name=".ShoppingCartActivity"
            android:exported="true" />
        <activity
            android:name=".ShoppingDetailActivity"
            android:exported="true" />
        <activity
            android:name=".ShoppingChannelActivity"
            android:exported="true">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>

</manifest>