android编辑购物车,Android制作简单的普通购物车

要制作一个简单的购物车功能，需要以下步骤：

1. 创建一个商品列表：在你的 Android 应用中创建一个列表，用于显示所有可购买的商品。

2. 添加购物车按钮：在每个商品项目上添加一个“加入购物车”按钮。

3. 创建购物车列表：创建一个新的列表，用于显示所有已添加到购物车中的商品。

4. 处理添加到购物车事件：当用户点击“加入购物车”按钮时，将所选商品添加到购物车列表中。

5. 显示购物车总价：在购物车列表底部添加一个元素，用于显示所有商品的总价。

以下是一个简单的示例代码，可以帮助你开始编写购物车功能：

1. 创建商品列表

public class MainActivity extends AppCompatActivity {
    private List<Product> productList = new ArrayList<>();

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

        // 添加商品
        productList.add(new Product("商品1", 10));
        productList.add(new Product("商品2", 20));
        productList.add(new Product("商品3", 30));

        // 设置商品列表
        RecyclerView recyclerView = findViewById(R.id.recyclerView);
        recyclerView.setLayoutManager(new LinearLayoutManager(this));
        recyclerView.setAdapter(new ProductAdapter(productList));
    }
}

2. 添加购物车按钮

public class ProductAdapter extends RecyclerView.Adapter<ProductAdapter.ViewHolder> {
    private List<Product> productList;

    public ProductAdapter(List<Product> productList) {
        this.productList = productList;
    }

    @NonNull
    @Override
    public ViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
        View view = LayoutInflater.from(parent.getContext())
                .inflate(R.layout.product_item, parent, false);

        return new ViewHolder(view);
    }

    @Override
    public void onBindViewHolder(@NonNull ViewHolder holder, int position) {
        Product product = productList.get(position);

        holder.nameTextView.setText(product.getName());
        holder.priceTextView.setText(String.valueOf(product.getPrice()));

        holder.addToCartButton.setOnClickListener(view -> {
            // 处理添加到购物车事件
        });
    }

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

    public static class ViewHolder extends RecyclerView.ViewHolder {
        public TextView nameTextView;
        public TextView priceTextView;
        public Button addToCartButton;

        public ViewHolder(@NonNull View itemView) {
            super(itemView);

            nameTextView = itemView.findViewById(R.id.nameTextView);
            priceTextView = itemView.findViewById(R.id.priceTextView);
            addToCartButton = itemView.findViewById(R.id.addToCartButton);
        }
    }
}

3. 创建购物车列表

public class CartActivity extends AppCompatActivity {
    private List<Product> cartList = new ArrayList<>();

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

        // 设置购物车列表
        RecyclerView recyclerView = findViewById(R.id.recyclerView);
        recyclerView.setLayoutManager(new LinearLayoutManager(this));
        recyclerView.setAdapter(new CartAdapter(cartList));
    }
}

4. 处理添加到购物车事件

public class MainActivity extends AppCompatActivity {
    private List<Product> productList = new ArrayList<>();
    private List<Product> cartList = new ArrayList<>();

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

        // 添加商品
        productList.add(new Product("商品1", 10));
        productList.add(new Product("商品2", 20));
        productList.add(new Product("商品3", 30));

        // 设置商品列表
        RecyclerView recyclerView = findViewById(R.id.recyclerView);
        recyclerView.setLayoutManager(new LinearLayoutManager(this));
        recyclerView.setAdapter(new ProductAdapter(productList, this::addToCart));
    }

    private void addToCart(Product product) {
        cartList.add(product);

        // 更新购物车列表
        RecyclerView recyclerView = findViewById(R.id.cartRecyclerView);
        CartAdapter adapter = (CartAdapter) recyclerView.getAdapter();
        adapter.notifyDataSetChanged();
    }
}

public class ProductAdapter extends RecyclerView.Adapter<ProductAdapter.ViewHolder> {
    private List<Product> productList;
    private OnAddToCartClickListener clickListener;

    public ProductAdapter(List<Product> productList, OnAddToCartClickListener clickListener) {
        this.productList = productList;
        this.clickListener = clickListener;
    }

    @NonNull
    @Override
    public ViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
        View view = LayoutInflater.from(parent.getContext())
                .inflate(R.layout.product_item, parent, false);

        return new ViewHolder(view);
    }

    @Override
    public void onBindViewHolder(@NonNull ViewHolder holder, int position) {
        Product product = productList.get(position);

        holder.nameTextView.setText(product.getName());
        holder.priceTextView.setText(String.valueOf(product.getPrice()));

        holder.addToCartButton.setOnClickListener(view -> {
            clickListener.onAddToCartClick(product);
        });
    }

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

    public static class ViewHolder extends RecyclerView.ViewHolder {
        public TextView nameTextView;
        public TextView priceTextView;
        public Button addToCartButton;

        public ViewHolder(@NonNull View itemView) {
            super(itemView);

            nameTextView = itemView.findViewById(R.id.nameTextView);
            priceTextView = itemView.findViewById(R.id.priceTextView);
            addToCartButton = itemView.findViewById(R.id.addToCartButton);
        }
    }

    public interface OnAddToCartClickListener {
        void onAddToCartClick(Product product);
    }
}

5. 显示购物车总价

public class CartActivity extends AppCompatActivity {
    private List<Product> cartList = new ArrayList<>();

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

        // 设置购物车列表
        RecyclerView recyclerView = findViewById(R.id.recyclerView);
        recyclerView.setLayoutManager(new LinearLayoutManager(this));
        recyclerView.setAdapter(new CartAdapter(cartList));

        // 设置购物车总价
        TextView totalPriceTextView = findViewById(R.id.totalPriceTextView);
        int totalPrice = 0;
        for (Product product : cartList) {
            totalPrice += product.getPrice();
        }
        totalPriceTextView.setText(String.valueOf(totalPrice));
    }
}

希望这个例子能帮助你开始制作购物车功能。