【Android】实现简易购物车功能（附源码）

先上结果：

代码：

首先引入图片加载：

implementation 'com.github.bumptech.glide:glide:4.15.1'

配置权限清单：

    <!-- 网络权限 --><uses-permission android:name="android.permission.INTERNET"/><uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>

页面布局：activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"xmlns:app="http://schemas.android.com/apk/res-auto"xmlns:tools="http://schemas.android.com/tools"android:layout_width="match_parent"android:layout_height="match_parent"android:orientation="vertical"tools:context=".MainActivity"><RelativeLayoutandroid:layout_width="match_parent"android:layout_height="?attr/actionBarSize"android:background="#2196F3"><TextViewandroid:id="@+id/personalCenterText"android:layout_width="wrap_content"android:layout_height="wrap_content"android:layout_centerInParent="true"android:text="购物车"android:textColor="#ffffff"android:textSize="24sp" /><TextViewandroid:id="@+id/edit"android:text="编辑"android:textColor="@color/white"android:textSize="24sp"android:layout_marginEnd="10dp"android:layout_centerVertical="true"android:layout_alignParentEnd="true"android:layout_width="wrap_content"android:layout_height="wrap_content"/></RelativeLayout><androidx.recyclerview.widget.RecyclerViewandroid:id="@+id/recyclerView"android:layout_weight="1"android:layout_width="match_parent"android:layout_height="0dp"/><RelativeLayoutandroid:layout_width="match_parent"android:layout_height="50dp"><CheckBoxandroid:id="@+id/allSelect"android:text="全选"android:layout_centerVertical="true"android:textColor="@color/colorAccent"android:layout_width="wrap_content"android:layout_height="wrap_content"/><TextViewandroid:id="@+id/total"android:textSize="20sp"android:text="合计0.00￥"android:textColor="@color/colorAccent"android:layout_centerVertical="true"android:layout_toStartOf="@id/pay"android:layout_marginEnd="10dp"android:layout_width="wrap_content"android:layout_height="wrap_content"/><Buttonandroid:id="@+id/pay"android:text="结算"android:textColor="@color/white"android:background="@drawable/button_red"android:layout_width="100dp"android:layout_alignParentEnd="true"android:layout_height="wrap_content"/></RelativeLayout></LinearLayout>

条目布局：item_cart.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"android:layout_width="match_parent"android:layout_height="100dp"><CheckBoxandroid:id="@+id/checkbox"android:layout_centerVertical="true"android:layout_width="wrap_content"android:layout_height="wrap_content"/><ImageViewandroid:id="@+id/cover"android:layout_width="80dp"android:layout_height="80dp"android:layout_margin="10dp"android:layout_toEndOf="@id/checkbox" /><LinearLayoutandroid:layout_toEndOf="@id/cover"android:layout_width="wrap_content"android:layout_height="wrap_content"android:orientation="vertical"><TextViewandroid:id="@+id/name"android:layout_width="wrap_content"android:layout_height="wrap_content"android:textStyle="bold"android:textSize="18sp"android:textColor="@color/black"android:maxLines="2"android:ellipsize="end"android:layout_marginTop="5dp" /><TextViewandroid:id="@+id/price"android:layout_width="wrap_content"android:layout_height="wrap_content"android:text=""android:textColor="#D32F2F"android:textStyle="bold"android:layout_marginTop="5dp" /></LinearLayout><LinearLayoutandroid:id="@+id/view_number"android:layout_width="wrap_content"android:layout_height="23dp"android:background="@drawable/shape_cart_item_add_cut_border"android:divider="@drawable/shape_divider_1_v"android:orientation="horizontal"android:showDividers="middle"android:layout_marginBottom="10dp"android:layout_marginEnd="10dp"android:layout_alignParentBottom="true"android:layout_alignParentEnd="true"><TextViewandroid:id="@+id/tv_reduce"android:layout_width="27dp"android:layout_height="match_parent"android:gravity="center"android:text="-"android:textColor="#676767"android:textSize="15sp"/><TextViewandroid:id="@+id/tv_num"android:layout_width="wrap_content"android:layout_height="match_parent"android:gravity="center"android:minWidth="40dp"android:paddingHorizontal="12dp"android:singleLine="true"android:text="1"android:textColor="#676767"android:textSize="15sp"/><TextViewandroid:id="@+id/tv_add"android:layout_width="27dp"android:layout_height="match_parent"android:gravity="center"android:text="+"android:textColor="#676767"android:textSize="15sp"/></LinearLayout>
</RelativeLayout>

资源文件：shape_cart_item_add_cut_border.xml

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"android:shape="rectangle"android:visible="true"><!-- 描边，边框 --><strokeandroid:width="1px"android:color="#E0E0E0"/><!--dashGap虚线段的间距、dashWidth虚线段的长度-->
</shape>

shape_divider_1_v.xml

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"android:shape="rectangle"android:visible="true"><sizeandroid:width="1px"/><!-- 宽度和高度 --><!-- 填充 --><solidandroid:color="#E0E0E0"/><!-- 填充的颜色 -->
</shape>

适配器：CartAdapter

public class CartAdapter extends RecyclerView.Adapter<CartAdapter.Holder> {private final List<CartBean> list;private final Context context;private final List<CartBean> selects=new ArrayList<>();public CartAdapter(List<CartBean> list, Context context) {this.list = list;this.context = context;}@NonNull@Overridepublic Holder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {View view= LayoutInflater.from(context).inflate(R.layout.item_cart,null,false);return new Holder(view);}@Overridepublic void onBindViewHolder(@NonNull Holder holder, int position) {CartBean cartBean =list.get(position);holder.name.setText(cartBean.getName());holder.number.setText(String.valueOf(cartBean.getNumber()));holder.price.setText(String.format("%1$.2f￥", cartBean.getPrice()));holder.reduce.setOnClickListener(new View.OnClickListener() {@Overridepublic void onClick(View view) {int n;n = Integer.parseInt(holder.number.getText().toString());if (n >1){n = n -1;holder.number.setText(String.valueOf(n));cartBean.setNumber(n);}else {Toast.makeText(context,"最少选择一件",Toast.LENGTH_SHORT).show();}updateItem();}});holder.add.setOnClickListener(new View.OnClickListener() {@Overridepublic void onClick(View view) {int n;n = Integer.parseInt(holder.number.getText().toString());n = n + 1;cartBean.setNumber(n);holder.number.setText(String.valueOf(n));updateItem();}});holder.checkBox.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {@Overridepublic void onCheckedChanged(CompoundButton compoundButton, boolean b) {cartBean.setSelect(b);updateItem();}});holder.checkBox.setChecked(cartBean.isSelect());Glide.with(context).load(cartBean.getCover()).into(holder.cover);}@Overridepublic int getItemCount() {return list.size();}public static class Holder extends RecyclerView.ViewHolder{CheckBox checkBox;ImageView cover;TextView name,number,reduce,add,price;public Holder(@NonNull View itemView) {super(itemView);checkBox=itemView.findViewById(R.id.checkbox);cover=itemView.findViewById(R.id.cover);name=itemView.findViewById(R.id.name);number=itemView.findViewById(R.id.tv_num);reduce=itemView.findViewById(R.id.tv_reduce);add=itemView.findViewById(R.id.tv_add);price=itemView.findViewById(R.id.price);}}private void updateItem(){selects.clear();for (CartBean cartBean:list){if (cartBean.isSelect()){selects.add(cartBean);}}onChange.change(selects);}public OnChange onChange;public void setOnChange(OnChange onChange) {this.onChange = onChange;}public List<CartBean> getSelects() {return selects;}//条目改变-接口回调public interface OnChange{void change(List<CartBean> selects);}
}

bean类：CartBean

public class CartBean {private String name;private String cover;private boolean isSelect;private int number;private double price;public String getName() {return name;}public void setName(String name) {this.name = name;}public String getCover() {return cover;}public void setCover(String cover) {this.cover = cover;}public boolean isSelect() {return isSelect;}public void setSelect(boolean select) {isSelect = select;}public int getNumber() {return number;}public void setNumber(int number) {this.number = number;}public double getPrice() {return price;}public void setPrice(double price) {this.price = price;}public CartBean(String name, String cover, boolean isSelect, int number, double price) {this.name = name;this.cover = cover;this.isSelect = isSelect;this.number = number;this.price = price;}@Overridepublic String toString() {return "CartBean{" +"name='" + name + '\'' +", cover='" + cover + '\'' +", isSelect=" + isSelect +", number=" + number +", price=" + price +'}';}
}

源码

github：https://github.com/panzhusheng/CartDemo
gitee：https://gitee.com/pan-zs/cart-demo