安卓开发案例-手机商城

1. 项目结构

2. 资源和配置

2.1 图片和布局文件

2.1.1 图片资源

2.1.2 布局文件

2.2 模块gradle配置

Room依赖

dependencies {
    implementation 'androidx.room:room-runtime:2.2.1'
    annotationProcessor 'androidx.room:room-runtime:2.2.1'
}

2.3 清单文件配置（AndroidManifest.xml）

2.3.1 配置文件读写权限

<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools">
    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
    <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
</manifest>

2.3.2 Application配置自己的.MyApplication

<application
        android:name=".MyApplication"
        android:allowBackup="true"
        android:dataExtractionRules="@xml/data_extraction_rules"
        android:fullBackupContent="@xml/backup_rules"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:requestLegacyExternalStorage="true"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="@style/Theme.MyApplication"
        tools:targetApi="31">
</application>

2.3.3启动Activity配置

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

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

    <meta-data
        android:name="android.app.lib_name"
        android:value="" />
</activity>

2.3.3其它Activity配置

<activity
    android:name=".activities.ShoppingDetailActivity"
    android:exported="false">
    <meta-data
        android:name="android.app.lib_name"
        android:value="" />
</activity>
<activity
    android:name=".activities.ShoppingCartActivity"
    android:exported="false">
    <meta-data
        android:name="android.app.lib_name"
        android:value="" />
</activity>

2.4 界面主题配置

2.5 常量配置

颜色常量

3. 代码

3.1 Activity代码

（1）购物车，ShoppingCartActivity.java

public class ShoppingCartActivity extends AppCompatActivity implements View.OnClickListener {
    private TextView tv_count;
    private ShoppingDBHelper mDBHelper;
    private LinearLayout ll_cart;
    private List<CartInfo> mCartList;
    private Map<Integer, GoodsInfo> mGoodsMap = new HashMap<>();
    private TextView tv_total_price;
    private LinearLayout ll_empty;
    private LinearLayout ll_content;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_shopping);

        TextView tv_title = findViewById(R.id.tv_title);
        tv_title.setText("购物车");
        findViewById(R.id.iv_back).setOnClickListener(this);
        findViewById(R.id.btn_clear).setOnClickListener(this);
        findViewById(R.id.btn_settle).setOnClickListener(this);
        findViewById(R.id.btn_shopping_channel).setOnClickListener(this);
        ll_empty = findViewById(R.id.ll_empty);
        ll_content = findViewById(R.id.ll_content);
        ll_cart = findViewById(R.id.ll_cart);
        tv_count = findViewById(R.id.tv_count);
        tv_count.setText(String.valueOf(MyApplication.getInstance().goodsCount));
        tv_total_price = findViewById(R.id.tv_total_price);
        mDBHelper = ShoppingDBHelper.getInstance(this);
    }

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

    private void showCart() {
        ll_cart.removeAllViews();
        mCartList = mDBHelper.queryAllCartInfo();
        if (mCartList.size() == 0) {
            showCount();
            return;
        }

        for (CartInfo info : mCartList) {
            GoodsInfo goods = mDBHelper.queryGoodsInfoById(info.goodsId);
            mGoodsMap.put(info.goodsId, goods);

            View view = LayoutInflater.from(this).inflate(R.layout.item_cart, null);
            ImageView iv_thumb = view.findViewById(R.id.iv_thumb);
            TextView tv_name = view.findViewById(R.id.tv_name);
            TextView tv_desc = view.findViewById(R.id.tv_desc);
            TextView tv_count = view.findViewById(R.id.tv_count);
            TextView tv_price = view.findViewById(R.id.tv_price);
            TextView tv_sum = view.findViewById(R.id.tv_sum);

            iv_thumb.setImageURI(Uri.parse(goods.picPath));
            tv_name.setText(goods.name);
            tv_desc.setText(goods.description);
            tv_count.setText(String.valueOf(info.count));
            tv_price.setText(String.valueOf((int)goods.price));
            tv_sum.setText(String.valueOf((int)(info.count * goods.price)));

            view.setOnLongClickListener(v -> {
                AlertDialog.Builder builder = new AlertDialog.Builder(ShoppingCartActivity.this);
                builder.setMessage("是否从购物车中删除" + goods.name + "? ");
                builder.setPositiveButton("是", (dialog, which) -> {
                    ll_cart.removeView(v);
                    deleteGoods(info);
                });

                builder.setNegativeButton("否", null);
                builder.create().show();
                return true;
            });

            view.setOnClickListener(v -> {
                Intent intent = new Intent(ShoppingCartActivity.this, ShoppingDetailActivity.class);
                intent.putExtra("goods_id", goods.id);
                startActivity(intent);
            });


            ll_cart.addView(view);
        }
        refreshTotalPrice();
    }

    private void deleteGoods(CartInfo info) {
        MyApplication.getInstance().goodsCount -= info.count;
        mDBHelper.deleteCartInfoByGoodsId(info.goodsId);
        CartInfo removed = null;
        for (CartInfo cartInfo : mCartList) {
            if (cartInfo.goodsId == info.goodsId) {
                removed = cartInfo;
                break;
            }
        }

        mCartList.remove(removed);

        showCount();
        ToastUtil.show(this, "已从购物车删除" + mGoodsMap.get(info.goodsId).name);
        mGoodsMap.remove(info.goodsId);
        refreshTotalPrice();
    }

    private void showCount() {
        tv_count.setText(String.valueOf(MyApplication.getInstance().goodsCount));
        if (MyApplication.getInstance().goodsCount == 0) {
            ll_empty.setVisibility(View.VISIBLE);
            ll_content.setVisibility(View.GONE);
            ll_cart.removeAllViews();
        } else {
            ll_content.setVisibility(View.VISIBLE);
            ll_empty.setVisibility(View.GONE);
        }
    }

    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:
                finish();
                break;
            case R.id.btn_shopping_channel:
                Intent intent = new Intent(this, ShoppingChannelActivity.class);
                intent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
                startActivity(intent);
                break;
            case R.id.btn_clear:
                mDBHelper.deteteAllCartInfo();
                MyApplication.getInstance().goodsCount = 0;
                showCount();
                ToastUtil.show(this, "购物车已清空");
                break;
            case R.id.btn_settle:
                Log.d(null,"-----------------------撒非得---------------------");
                AlertDialog.Builder builder = new AlertDialog.Builder(ShoppingCartActivity.this);
                builder.setTitle("结算商品");
                builder.setMessage("客观抱歉，支付功能尚未开通，请下次再来");
                builder.setPositiveButton("我知道了", null);
                builder.create().show();
                break;
        }
    }
}

（2）手机商城，ShoppingChannelActivity.java

public class ShoppingChannelActivity extends AppCompatActivity implements View.OnClickListener {

    private ShoppingDBHelper mDBHelper;
    private TextView tv_title;
    private TextView tv_count;
    private GridLayout gl_channel;

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

        findViewById(R.id.iv_back).setOnClickListener(this);
        findViewById(R.id.iv_cart).setOnClickListener(this);

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

        showGoods();
    }

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

    private void showCartInfoTotal() {
        int count = mDBHelper.countCartInfo();
        MyApplication .getInstance().goodsCount = count;
        tv_count.setText(String.valueOf(count));
    }

    private void showGoods() {
        int screenWidth = getResources().getDisplayMetrics().widthPixels;
        LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(
                screenWidth / 2, LinearLayout.LayoutParams.WRAP_CONTENT);

        gl_channel.removeAllViews();

        List<GoodsInfo> list = mDBHelper.queryGoodsInfo();
        for (GoodsInfo info : list) {
            View view = LayoutInflater.from(this).inflate(R.layout.item_goods, null);
            ImageView iv_thumb = view.findViewById(R.id.iv_thumb);
            TextView tv_name = view.findViewById(R.id.tv_name);
            TextView tv_price = view.findViewById(R.id.tv_price);
            Button btn_add = view.findViewById(R.id.btn_add);
            iv_thumb.setImageURI(Uri.parse(info.picPath));
            tv_name.setText(info.name);
            tv_price.setText(String.valueOf((int)info.price));

            btn_add.setOnClickListener(v -> {
                addToChart(info.id, info.name);
            });

            view.setOnClickListener(v -> {
                Intent intent = new Intent(ShoppingChannelActivity.this, ShoppingDetailActivity.class);
                intent.putExtra("goods_id", info.id);
                startActivity(intent);
            });


            gl_channel.addView(view, params);
        }
    }

    private void addToChart(int goodsId, String goodsName) {
        int count = ++MyApplication.getInstance().goodsCount;
        tv_count.setText(String.valueOf(count));
        mDBHelper.insertChartInfo(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:
                finish();
                break;
            case R.id.iv_cart:
                Intent intent = new Intent(this, ShoppingCartActivity.class);
                intent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
                startActivity(intent);
                break;
            default:
                break;
        }
    }
}

（3）商品详情，ShoppingChannelActivity.java

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);
        iv_goods_pic = findViewById(R.id.iv_goods_pic);
        tv_goods_desc = findViewById(R.id.tv_goods_desc);

        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() {
        mGoodsId = getIntent().getIntExtra("goods_id", 0);
        if (mGoodsId > 0) {
            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) {
        int count = ++MyApplication.getInstance().goodsCount;
        tv_count.setText(String.valueOf(count));
        mDBHelper.insertChartInfo(goodsId);
        ToastUtil.show(this, "成功添加至购物车");
    }
}

3.2 数据库代码

ShoppingDBHelper.java

public class ShoppingDBHelper extends SQLiteOpenHelper {
    private static final String DB_NAME = "shopping.db";
    private static final String TABLE_GOODS_INFO = "goods_info";
    private static final String TABLE_CART_INFO = "cart_info";
    private static final int DB_VERSION = 1;
    private static ShoppingDBHelper mHelper = null;
    private SQLiteDatabase mRDB;
    private SQLiteDatabase mWDB;

    public ShoppingDBHelper(@Nullable Context context) {
        super(context, DB_NAME, null, DB_VERSION);
    }

    public static ShoppingDBHelper getInstance(Context context) {
        if (mHelper == null) {
            mHelper = new ShoppingDBHelper(context);
        }
        return mHelper;
    }

    @Override
    public void onCreate(SQLiteDatabase db) {
        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);

        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 sqLiteDatabase, int i, int i1) {

    }

    public List<GoodsInfo> queryGoodsInfo(){
        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;
    }

    public void insertGoodsInfos(List<GoodsInfo> list) {
        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();
        }
    }

    public void closeLink() {
        if (mRDB != null && mRDB.isOpen()) {
            mRDB.close();
            mRDB = null;
        }

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

    public SQLiteDatabase openWriteLink() {
        if (mWDB == null || !mWDB.isOpen()) {
            mWDB = mHelper.getWritableDatabase();
        }
        return mWDB;
    }

    public SQLiteDatabase openReadLink() {
        if (mRDB == null || !mRDB.isOpen()) {
            mRDB = mHelper.getReadableDatabase();
        }
        return mRDB;
    }

    public void insertChartInfo(int goodsId) {
        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 {
            values.put("_id", cartInfo.id);
            values.put("count", ++cartInfo.count);
            mWDB.update(TABLE_CART_INFO, values, "_id=?", new String[]{String.valueOf(cartInfo.id)});

        }
    }

    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;
    }

    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;
    }

    public List<CartInfo> queryAllCartInfo() {
        List<CartInfo> list = new ArrayList<>();
        Cursor cursor = mRDB.query(TABLE_CART_INFO, null, 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;
    }

    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;
    }

    public void deleteCartInfoByGoodsId(int goodsId) {
        mWDB.delete(TABLE_CART_INFO, "goods_id=?", new String[]{String.valueOf(goodsId)});
    }

    public void deteteAllCartInfo(){
        mWDB.delete(TABLE_CART_INFO, "1=1",null);
//        mWDB.delete(TABLE_CART_INFO, null,null);
    }
}

3.3 实体类

CartInfo .java

package com.example.myapplication.entity;

public class CartInfo {
    public int id;
    public int goodsId;
    public int count;

    public CartInfo() {}
}

GoodsInfo .java

public class GoodsInfo {
    public int id;
    public String name;
    public String description;
    public float price;
    public String picPath;
    public int pic;

    public GoodsInfo(int id, String name, String description, float price, String picPath, int pic) {
        this.id = id;
        this.name = name;
        this.description = description;
        this.price = price;
        this.picPath = picPath;
        this.pic = pic;
    }

    private static String[] mNameArray = {"iPhone11", "Mate30", "小米10", "OPPO Reno3", "VIVO X30", "荣耀30S"};

    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"
    };

    private static float[] mPriceArray = {6299, 4999, 3999, 2999, 2998, 2399};

    public static int[] mPicArray = {
            R.drawable.xiaomi, R.drawable.img2,
            R.drawable.img3, R.drawable.img4,
            R.drawable.img5, R.drawable.img6,
    };

    public GoodsInfo() {

    }

    public static ArrayList<GoodsInfo> getDefaultList() {
        ArrayList<GoodsInfo> goodsList = new ArrayList<>();
        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;
    }

}

3.4 Util 工具类

FileUtil .java

package com.example.myapplication.util;

import android.graphics.Bitmap;

import java.io.FileOutputStream;
import java.io.IOException;

public class FileUtil {
    public static void SaveImage(String path, Bitmap bitmap) {
        FileOutputStream fos = null;
        try {
            fos = new FileOutputStream(path);
            bitmap.compress(Bitmap.CompressFormat.PNG, 100, fos);
        }catch (Exception e) {
            e.printStackTrace();
        }finally {
            if (fos != null) {
                try {
                    fos.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
    }
}

SharedUtil .java

package com.example.myapplication.util;

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);
    }
}

ToastUtil .java

package com.example.myapplication.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();
    }
}

3.5 MyApplication.java

public class MyApplication extends Application {
    public static MyApplication mApp;
    public HashMap<String, String>  infoMap = new HashMap<>();

    public static MyApplication getInstance() {
        return mApp;
    }
    public int goodsCount;

    private void initGoodsInfo(){
        boolean isFirst = SharedUtil.getInstance(this).readBoolean("first", true);
        String directory = getExternalFilesDir(Environment.DIRECTORY_DOWNLOADS).toString() + File.separator;
        if (isFirst) {
            List<GoodsInfo> list = GoodsInfo.getDefaultList();
            for (GoodsInfo info : list) {
                Bitmap bitmap = BitmapFactory.decodeResource(getResources(), info.pic);
                String path = directory + info.id + ".png";
                FileUtil.SaveImage(path, bitmap);

                bitmap.recycle();
                info.picPath = path;
            }

            ShoppingDBHelper dbHelper = ShoppingDBHelper.getInstance(this);
            dbHelper.openWriteLink();
            dbHelper.insertGoodsInfos(list);
            dbHelper.closeLink();
            SharedUtil.getInstance(this).writeBoolean("first", false);
        }
    }

    @Override
    public void onCreate() {
        super.onCreate();
        mApp = this;
        initGoodsInfo();
    }

    @Override
    public void onTerminate() {
        super.onTerminate();

        Log.d("HKHL", "MyApplication onTerminate");
    }

    @Override
    public void onConfigurationChanged(@NonNull Configuration newConfig) {
        super.onConfigurationChanged(newConfig);
        Log.d("HKHL", "MyApplication onConfigurationChanged");
    }
}

3.6 布局代码

activity_shopping.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: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="0dp"
                        android:layout_height="wrap_content"
                        android:layout_weight="1"
                        android:gravity="center"
                        android:textSize="15sp"
                        android:textColor="@color/black"
                        android:text="图片"
                        >
                    </TextView>
                    <TextView
                        android:layout_width="0dp"
                        android:layout_height="wrap_content"
                        android:layout_weight="2"
                        android:gravity="center"
                        android:textSize="15sp"
                        android:textColor="@color/black"
                        android:text="名称"
                        >
                    </TextView>

                    <TextView
                        android:layout_width="0dp"
                        android:layout_height="wrap_content"
                        android:layout_weight="1"
                        android:textSize="15sp"
                        android:textColor="@color/black"
                        android:gravity="center"
                        android:text="数量"
                        >
                    </TextView>
                    <TextView
                        android:layout_width="0dp"
                        android:layout_height="wrap_content"
                        android:layout_weight="1"
                        android:textSize="15sp"
                        android:textColor="@color/black"
                        android:gravity="center"
                        android:text="单价"
                        >
                    </TextView>
                    <TextView
                        android:layout_width="0dp"
                        android:layout_height="wrap_content"
                        android:layout_weight="1"
                        android:textSize="15sp"
                        android:textColor="@color/black"
                        android:gravity="center"
                        android:text="总价"
                        >
                    </TextView>
                </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="0dp"
                        android:layout_weight="1"
                        android:layout_height="wrap_content"
                        android:gravity="center"
                        android:textSize="15sp"
                        android:text="清空"
                        >
                    </Button>
                    <TextView
                        android:layout_width="0dp"
                        android:layout_height="wrap_content"
                        android:layout_weight="1"
                        android:gravity="center"
                        android:textColor="@color/black"
                        android:textSize="15sp"
                        android:text="总金额:"
                        >
                    </TextView>
                    <TextView
                        android:id="@+id/tv_total_price"
                        android:layout_width="0dp"
                        android:layout_height="wrap_content"
                        android:layout_weight="1"
                        android:gravity="center"
                        android:textColor="@color/red"
                        android:textSize="17sp"
                        >
                    </TextView>
                    <Button
                        android:id="@+id/btn_settle"
                        android:layout_width="0dp"
                        android:layout_height="wrap_content"
                        android:layout_weight="1"
                        android:textSize="17sp"
                        android:text="结算"
                        >
                    </Button>
                </LinearLayout>
            </LinearLayout>

            <LinearLayout
                android:id="@+id/ll_empty"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:orientation="vertical"
                android:visibility="gone"
                >
                <TextView
                    android:layout_width="match_parent"
                    android:layout_height="wrap_content"
                    android:layout_marginTop="100dp"
                    android:layout_marginBottom="100dp"
                    android:gravity="center"
                    android:textSize="17sp"
                    android:text="哎呀，购物车空空如也，快去选购商品吧">
                </TextView>
                <Button
                    android:id="@+id/btn_shopping_channel"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:textSize="17sp"
                    android:layout_gravity="center"
                    android:text="逛逛手机商场"
                    >
                </Button>
            </LinearLayout>
        </RelativeLayout>
    </ScrollView>
</LinearLayout>

\

activity_shopping_channel.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:background="@color/orange"
    android:orientation="vertical"
    >
    <include layout="@layout/title_shopping" />
    <ScrollView
        android:layout_width="match_parent"
        android:layout_height="wrap_content">
        <GridLayout
            android:id="@+id/gl_channel"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:columnCount="2"
            >
        </GridLayout>
    </ScrollView>
</LinearLayout>

activity_shopping_detail.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:layout_width="match_parent"
    android:layout_height="wrap_content"
    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"
                android: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"
                android:text="1990" />
            <TextView
                android:id="@+id/tv_goods_desc"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:paddingLeft="5dp"
                android:textSize="15sp"
                android:textColor="@color/black"
                android: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>

item_cart.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="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"
        android: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"
            android: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"
            android: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"
        android: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"
        android: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"
        android:text="2000"
        />
</LinearLayout>

item_goods.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    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"
        android:text="小米手机"
        ></TextView>
    <ImageView
        android:id="@+id/iv_thumb"
        android:layout_width="180dp"
        android:layout_height="150dp"
        android:scaleType="fitCenter"
        android:src="@drawable/xiaomi"
        >
    </ImageView>
    <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"
            android:text="20"
            ></TextView>
        <Button
            android:id="@+id/btn_add"
            android:layout_width="0dp"
            android:layout_height="match_parent"
            android:layout_weight="3"
            android:gravity="center"
            android:textColor="@color/black"
            android:textSize="15sp"
            android:text="加入购物车"
            >
        </Button>
    </LinearLayout>
</LinearLayout>

title_shopping.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:background="#aaaaff"
    android:layout_height="50dp">
    <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"
        >
    </ImageView>
    <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/ic_cart"
        >
    </ImageView>
    <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"

        android:text="">
    </TextView>
    <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">
    </TextView>
</RelativeLayout>

4. 结果演示