京东购物车

最新推荐文章于 2022-06-09 14:37:46 发布

原创最新推荐文章于 2022-06-09 14:37:46 发布 · 475 阅读

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本文详细介绍了一种购物车多级列表的实现方案，包括商家和商品层级的管理，使用复选框控制商品和商家的选择状态，以及总价的实时计算。通过自定义适配器和加减器，实现了商品数量的调整和总价的更新。

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最下面是0级列表

商家 -- 1级

商品 -- 2级

需要注意的三个点：
- 0 -- 选中/未选中
- 1 -- 选中/未选中
- 2 -- 选中/未选中

CheckBox会发生复用问题

给它设置点击事件，每次都要对每个位置的box状态进行记录

圆角矩形、扁平化设计风格

F9:0A:2A:29:99:84:EB:F3:E9:7D:CC:9D:E1:AE:06:68:58:CC:52:06

购物车ShopperAdapter()

/**
 * ShopperAdapter
 * 商家适配器
 */
public class ShopperAdapter extends RecyclerView.Adapter<ShopperAdapter.ViewHolder> {
    private Context context;
    private List<Shopper<List<Product>>> list;

    public ShopperAdapter(Context context, List<Shopper<List<Product>>> list) {
        this.context = context;
        this.list = list;
    }

    // 一级列表（商家）发生变化的接口
    public interface OnShopperClickListener {
        void onShopperClick(int position, boolean isCheck);
    }

    private OnShopperClickListener shopperClickListener;

    public void setOnShopperClickListener(OnShopperClickListener listener) {
        this.shopperClickListener = listener;
    }


    // 二级列表的加减器监听
    private ProductAdapter.OnAddDecreaseProductListener productListener;

    public void setOnAddDecreaseProductListener(ProductAdapter.OnAddDecreaseProductListener listener) {
        this.productListener = listener;
    }

    @NonNull
    @Override
    public ViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
        View v = View.inflate(context, R.layout.item_shopper, null);
        ViewHolder holder = new ViewHolder(v);
        return holder;
    }

    @Override
    public void onBindViewHolder(@NonNull final ViewHolder holder, final int position) {
        final Shopper<List<Product>> shopper = list.get(position);
        holder.txtShopperName.setText(shopper.getSellerName());

        // 产品的列表
        RecyclerView.LayoutManager pLayoutManager = new LinearLayoutManager(context);
        holder.rvProduct.setLayoutManager(pLayoutManager);
        final ProductAdapter adapter = new ProductAdapter(context, shopper.getList());
        // 给二级列表添加一个加减器的监听
        if (productListener != null) {
            adapter.setOnAddDecreaseProductListener(productListener);
        }
        // 二级条目（商品）复选框点击事件
        adapter.setOnProductClickListener(new ProductAdapter.OnProductClickListener() {
            @Override
            public void onProductClick(int position, boolean isChecked) {
                // 当前商品未选中，商家也就未选中
                if (!isChecked) {
                    shopper.setChecked(false);
                    // 只要是当前条目未选中，全选复选框也就没选中
                    shopperClickListener.onShopperClick(position, false);
                } else {
                    // 当前商品如果选中，需要遍历商家所有的商品是否选中
                    // 循环遍历之前先设置一个true标志位，只要有一条商品没有被选中，商家也就选中，标志位变成false
                    boolean isAllProductSelected = true;
                    for (Product product : shopper.getList()) {
                        if (!product.isChecked()) {
                            isAllProductSelected = false;
                            break;
                        }
                    }
                    shopper.setChecked(isAllProductSelected);
                    // 当前商品选中时，需要循环遍历所有的商家是否被选中来确认外部全选复选框的状态
                    shopperClickListener.onShopperClick(position, true);
                }
                // 数据发生变化之后刷新适配器
                notifyDataSetChanged();
                productListener.onChange(0, 0);
            }
        });

        holder.rvProduct.setAdapter(adapter);

        // 先取消掉之前的点击变化监听
        holder.cbSHopper.setOnCheckedChangeListener(null);

        // 设置好初始化的状态
        holder.cbSHopper.setChecked(shopper.isChecked());

        // 等设置完初始化状态之后再设置我们自己的监听
        // 商家列表中的复选框
        holder.cbSHopper.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
            @Override
            public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
                shopper.setChecked(isChecked);

                // 1.商家被选中的时候，子类所有的商品应该被选中
//                if (isChecked) {
                List<Product> productList = shopper.getList();
                for (Product product : productList) {
                    product.setChecked(isChecked);
                }
                // 子类商品的适配器刷新
                adapter.notifyDataSetChanged();
//                }
                // 当点击一级条目的时候，外部的全选按钮状态发生变化
                if (shopperClickListener != null) {
                    shopperClickListener.onShopperClick(position, isChecked);
                }
            }
        });
    }

    @Override
    public int getItemCount() {
        return list.size();
    }

    class ViewHolder extends RecyclerView.ViewHolder {
        private CheckBox cbSHopper;
        private TextView txtShopperName;
        private RecyclerView rvProduct;

        public ViewHolder(View itemView) {
            super(itemView);
            cbSHopper = itemView.findViewById(R.id.cb_shopper);
            txtShopperName = itemView.findViewById(R.id.txt_shopper_name);
            rvProduct = itemView.findViewById(R.id.rv_product);
        }
    }
}

商品ShopperAdapter

/**
 * ProductAdapter  商品适配器
 */

public class ProductAdapter extends RecyclerView.Adapter<ProductAdapter.ViewHolder> {
    private Context context;
    private List<Product> list;

    // 二级条目（商品）点击监听
    public interface OnProductClickListener {
        void onProductClick(int position, boolean isChecked);
    }

    private OnProductClickListener productClickListener;

    public void setOnProductClickListener(OnProductClickListener listener) {
        this.productClickListener = listener;
    }

    // 加减器发生变化的监听
    public interface OnAddDecreaseProductListener {
        void onChange(int position, int num);
    }

    private OnAddDecreaseProductListener productListener;

    public void setOnAddDecreaseProductListener(OnAddDecreaseProductListener listener) {
        this.productListener = listener;
    }

    public ProductAdapter(Context context, List<Product> list) {
        this.context = context;
        this.list = list;
    }

    @NonNull
    @Override
    public ViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
        View v = View.inflate(context, R.layout.item_product, null);
        ViewHolder holder = new ViewHolder(v);
        return holder;
    }

    @Override
    public void onBindViewHolder(@NonNull ViewHolder holder, final int position) {
        final Product product = list.get(position);
        String images = product.getImages();
        // 商品图片
        if (!TextUtils.isEmpty(images)) {
            String[] strings = images.split("\\|");
            if (strings.length > 0) {
                Glide.with(context)
                        .load(StringUtils.https2Http(strings[0]))
                        .into(holder.imgProduct);
            }
        }

        holder.txtProductName.setText(product.getTitle());
        holder.txtSinglePriice.setText(String.valueOf(product.getPrice()));

        holder.advProduct.setNum(product.getNum());
        // 加减器添加点击事件
        holder.advProduct.setOnAddDecreaseClickListener(new AddDecreaseView.OnAddDecreaseClickListener() {
            @Override
            public void add(int num) {
                product.setNum(num);

                if (productListener != null) {
                    productListener.onChange(position, num);
                }
            }

            @Override
            public void decrease(int num) {
                product.setNum(num);
                if (productListener != null) {
                    productListener.onChange(position, num);
                }
            }
        });


        // 商品的复选框
        holder.cbProduct.setOnCheckedChangeListener(null);
        holder.cbProduct.setChecked(product.isChecked());
        holder.cbProduct.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
            @Override
            public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
                product.setChecked(isChecked);
                if (productClickListener != null) {
                    productClickListener.onProductClick(position, isChecked);
                }
            }
        });

    }

    @Override
    public int getItemCount() {
        return list.size();
    }

    class ViewHolder extends RecyclerView.ViewHolder {
        private CheckBox cbProduct;
        private ImageView imgProduct;
        private TextView txtProductName;
        private TextView txtSinglePriice;
        private AddDecreaseView advProduct;

        public ViewHolder(View itemView) {
            super(itemView);
            cbProduct = itemView.findViewById(R.id.cb_product);
            imgProduct = itemView.findViewById(R.id.img_product);
            txtSinglePriice = itemView.findViewById(R.id.txt_single_price);
            advProduct = itemView.findViewById(R.id.adv_product);
            txtProductName = itemView.findViewById(R.id.txt_product_name);
        }
    }
}

自定义加减器

/**
 * AddDecreaseView，自定义加减器
 */

public class AddDecreaseView extends RelativeLayout implements View.OnClickListener {
    private TextView txtAdd;
    private TextView txtDecrease;
    private TextView txtNum;

    private int num;

    public interface OnAddDecreaseClickListener {
        void add(int num);

        void decrease(int num);
    }


    private OnAddDecreaseClickListener listener;

    public void setOnAddDecreaseClickListener(OnAddDecreaseClickListener listener) {
        this.listener = listener;
    }

    public AddDecreaseView(Context context) {
        this(context, null);
    }

    public AddDecreaseView(Context context, AttributeSet attrs) {
        this(context, attrs, 0);
    }

    public AddDecreaseView(Context context, AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
        init(context);
    }

    private void init(Context context) {
        View.inflate(context, R.layout.item_add_decrease, this);
        txtAdd = findViewById(R.id.txt_add);
        txtDecrease = findViewById(R.id.txt_decrease);
        txtNum = findViewById(R.id.txt_num);

        txtNum.setText("1");

        txtAdd.setOnClickListener(this);
        txtDecrease.setOnClickListener(this);

    }

    public void setNum(int num) {
        this.num = num;
        txtNum.setText(num + "");
    }

    public int getNum() {
        return num;
    }

    @Override
    public void onClick(View v) {
        switch (v.getId()) {
            case R.id.txt_add:
                num++;
                txtNum.setText(num + "");
                if (listener != null) {
                    listener.add(num);
                }
                break;
            case R.id.txt_decrease:
                if (num > 1) {
                    num--;
                }
                txtNum.setText(num + "");
                if (listener != null) {
                    listener.decrease(num);
                }
                break;
        }
    }
}

MainActvity页面：

public class MainActivity extends AppCompatActivity implements IView {
    private static final String TAG = "MainActivity";
    //    MessageBean<List<ShopperAdapter<List<Product>>>>
    private TextView txtEditFinish;
    private CheckBox cbTotal;
    private TextView txtPrice;
    private Button btnCalu;
    private RecyclerView rvShoper;

    private CartPresenter presenter;
    private ShopperAdapter adapter;

    private List<Shopper<List<Product>>> list;

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

        initView();
        initData();
        setListener();

    }

    private void setListener() {
        cbTotal.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                boolean isChecked = cbTotal.isChecked();
                // 遍历一级列表，和下方的全选状态一致
                for (Shopper<List<Product>> listShopper : list) {
                    listShopper.setChecked(isChecked);
                    // 遍历二级列表，和下方的全选状态一致
                    List<Product> products = listShopper.getList();
                    for (Product product : products) {
                        product.setChecked(isChecked);
                    }
                }
                calculatePrice();
                adapter.notifyDataSetChanged();
            }
        });
    }

    private void initData() {
        list = new ArrayList<>();
        // 商家的列表
        adapter = new ShopperAdapter(this, list);
        // 添加一级条目（商家）状态发生变化时
        adapter.setOnShopperClickListener(new ShopperAdapter.OnShopperClickListener() {
            @Override
            public void onShopperClick(int position, boolean isCheck) {
                // 为了效率考虑，当点击状态变成未选中时，全选按钮肯定就不是全选了，就不用再循环一次
                if (!isCheck) {
                    cbTotal.setChecked(false);
                } else {
                    // 如果是商家变成选中状态时，需要循环遍历所有的商家是否被选中
                    // 循环遍历之前先设置一个true标志位，只要有一个是未选中就改变这个标志位为false
                    boolean isAllShopperChecked = true;
                    for (Shopper<List<Product>> listShopper : list) {
                        // 只要有一个商家没有被选中，全选复选框就变成未选中状态，并且结束循环
                        if (!listShopper.isChecked()) {
                            isAllShopperChecked = false;
                            break;
                        }
                    }
                    cbTotal.setChecked(isAllShopperChecked);
                }

                // 一级条目发生变化时，计算一下总价
                calculatePrice();
            }
        });


        adapter.setOnAddDecreaseProductListener(new ProductAdapter.OnAddDecreaseProductListener() {
            @Override
            public void onChange(int position, int num) {
                calculatePrice();
            }
        });


        RecyclerView.LayoutManager layoutManager = new LinearLayoutManager(this);
        rvShoper.setLayoutManager(layoutManager);
        rvShoper.addItemDecoration(new DividerItemDecoration(this, DividerItemDecoration.VERTICAL));
        rvShoper.setAdapter(adapter);

        presenter = new CartPresenter();
        presenter.attach(this);
        presenter.getData();
    }

    // 计算商品总价
    private void calculatePrice() {
        // 遍历商家
        float totalPrice = 0;
        for (Shopper<List<Product>> listShopper : list) {
            // 遍历商家的商品
            List<Product> list = listShopper.getList();
            for (Product product : list) {
                // 如果商品被选中
                if (product.isChecked()) {
                    totalPrice += product.getNum() * product.getPrice();
                }
            }
        }

        txtPrice.setText("总价：" + totalPrice);

    }

    private void initView() {
        txtEditFinish = findViewById(R.id.txt_edit_or_finish);
        cbTotal = findViewById(R.id.cb_total_select);
        txtPrice = findViewById(R.id.txt_total_price);
        btnCalu = findViewById(R.id.btn_calu);
        rvShoper = findViewById(R.id.rv_shopper);
    }

    @Override
    public void success(MessageBean<List<Shopper<List<Product>>>> data) {
        if (data != null) {
            // 获取商家列表
            List<Shopper<List<Product>>> shoppers = data.getData();
            if (shoppers != null) {
                list.clear();
                list.addAll(shoppers);
                adapter.notifyDataSetChanged();
            }
        }
    }

    @Override
    public void failed(Exception e) {
        Toast.makeText(this, e.getMessage(), Toast.LENGTH_SHORT).show();
    }

    @Override
    protected void onDestroy() {
        super.onDestroy();
        if (presenter != null) {
            presenter.detach();
        }
    }
}