使用ExpandableListView实现购物车

 GitHub源码地址：https://github.com/BnerFang/MonthlyTest_1220

bean类

public class GetCartBean {

    private String msg;
    private String code;

    private List data;

    public String getMsg() {
        return msg;
    }

    public void setMsg(String msg) {
        this.msg = msg;
    }

    public String getCode() {
        return code;
    }

    public void setCode(String code) {
        this.code = code;
    }

    public List getData() {
        return data;
    }

    public void setData(List data) {
        this.data = data;
    }

    public static class DataBean {
        private boolean checked;//自己添加的

        public boolean isChecked() {
            return checked;
        }

        public void setChecked(boolean checked) {
            this.checked = checked;
        }

        private String sellerName;
        private String sellerid;


        private List list;

        public String getSellerName() {
            return sellerName;
        }

        public void setSellerName(String sellerName) {
            this.sellerName = sellerName;
        }

        public String getSellerid() {
            return sellerid;
        }

        public void setSellerid(String sellerid) {
            this.sellerid = sellerid;
        }

        public List getList() {
            return list;
        }

        public void setList(List list) {
            this.list = list;
        }

        public static class ListBean {
            private boolean checked;//自己添加的
            private int count = 1;//自己添加的

            public boolean isChecked() {
                return checked;
            }

            public void setChecked(boolean checked) {
                this.checked = checked;
            }

            public int getCount() {
                return count;
            }

            public void setCount(int count) {
                this.count = count;
            }

            private double bargainPrice;
            private String createtime;
            private String detailUrl;
            private String images;
            private int num;
            private int pid;
            private double price;
            private int pscid;
            private int selected;
            private int sellerid;
            private String subhead;
            private String title;

            public double getBargainPrice() {
                return bargainPrice;
            }

            public void setBargainPrice(double bargainPrice) {
                this.bargainPrice = bargainPrice;
            }

            public String getCreatetime() {
                return createtime;
            }

            public void setCreatetime(String createtime) {
                this.createtime = createtime;
            }

            public String getDetailUrl() {
                return detailUrl;
            }

            public void setDetailUrl(String detailUrl) {
                this.detailUrl = detailUrl;
            }

            public String getImages() {
                return images;
            }

            public void setImages(String images) {
                this.images = images;
            }

            public int getNum() {
                return num;
            }

            public void setNum(int num) {
                this.num = num;
            }

            public int getPid() {
                return pid;
            }

            public void setPid(int pid) {
                this.pid = pid;
            }

            public double getPrice() {
                return price;
            }

            public void setPrice(double price) {
                this.price = price;
            }

            public int getPscid() {
                return pscid;
            }

            public void setPscid(int pscid) {
                this.pscid = pscid;
            }

            public int getSelected() {
                return selected;
            }

            public void setSelected(int selected) {
                this.selected = selected;
            }

            public int getSellerid() {
                return sellerid;
            }

            public void setSellerid(int sellerid) {
                this.sellerid = sellerid;
            }

            public String getSubhead() {
                return subhead;
            }

            public void setSubhead(String subhead) {
                this.subhead = subhead;
            }

            public String getTitle() {
                return title;
            }

            public void setTitle(String title) {
                this.title = title;
            }
        }
    }
}

MVP

callback

public interface CarCallBack {
        void onSuccess(List group, List> child);
        void onFailed(String error);
}

 

//用于计算价钱和总数的bean放在mvp里

public class PriceAndCount {
    private double price;
    private int count;

    public PriceAndCount(double price, int count) {
        this.price = price;
        this.count = count;
    }

    public double getPrice() {
        return price;
    }

    public void setPrice(double price) {
        this.price = price;
    }

    public int getCount() {
        return count;
    }

    public void setCount(int count) {
        this.count = count;
    }
}

 

view层 

 

public interface CarView {
    void onCarSuccess(List group, List> child);
    void onCarFailed(String error);
}

 model层

public class CarModel {

    public void carData(List group, List> child, int pid, final CarCallBack carCallBack) {
        new OkHttpUtil().OkHttpGet(Apis.CAR_URL + pid).setOkHttpListener(new OkHttpUtil.OkHttpListener() {
            @Override
            public void OkHttpSuccess(String data) {
                Gson gson = new Gson();
                GetCartBean getCartBean = gson.fromJson(data, GetCartBean.class);
                List dataBeans = getCartBean.getData();
                List> lists = new ArrayList<>();
                for (int i = 0; i < dataBeans.size(); i++){
                    lists.add(dataBeans.get(i).getList());
                }
                if (getCartBean.getCode().equals("0")) {
                    carCallBack.onSuccess(dataBeans, lists);
                } else {
                    carCallBack.onFailed(getCartBean.getMsg());
                }
            }

            @Override
            public void OkHttpError(String error) {
                carCallBack.onFailed(error);
            }
        });
    }
}

presenter层

public class CarPresenter {
    private CarView mICarView;
    private CarModel mCarModel;

    public CarPresenter(CarView ICarView) {
        mICarView = ICarView;
        mCarModel = new CarModel();
    }

    public void datechView() {
        mICarView = null;
    }

    public void carDatas(List group, List> child, int pid) {
        mCarModel.carData(group, child, pid, new CarCallBack() {
            @Override
            public void onSuccess(List group, List> child) {
                mICarView.onCarSuccess(group, child);
            }

            @Override
            public void onFailed(String error) {
                mICarView.onCarFailed(error);
            }
        });
    }
}

ExpandableListView适配器

public class ElvAdapter extends BaseExpandableListAdapter {
    private final LayoutInflater inflater;
    private Context context;
    private List group;
    private List> child;


    public ElvAdapter(Context context, List group, List> child) {
        this.context=context;
        this.group=group;
        this.child=child;
        inflater = LayoutInflater.from(context);
    }

    @Override
    public int getGroupCount() {
        return group.size();
    }

    @Override
    public int getChildrenCount(int groupPosition) {
        return child.get(groupPosition).size();
    }

    @Override
    public Object getGroup(int groupPosition) {
        return group.get(groupPosition);
    }

    @Override
    public Object getChild(int groupPosition, int childPosition) {
        return child.get(groupPosition).get(childPosition);
    }

    @Override
    public long getGroupId(int groupPosition) {
        return groupPosition;
    }

    @Override
    public long getChildId(int groupPosition, int childPosition) {
        return childPosition;
    }

    @Override
    public boolean hasStableIds() {
        return false;
    }

    @Override
    public View getGroupView(final int groupPosition, boolean isExpanded, View convertView, ViewGroup parent) {
        View view;
        final GroupViewHolder holder;
        if (convertView == null) {
            view = inflater.inflate(R.layout.elv_group, null);
            holder = new GroupViewHolder();
            holder.tv = view.findViewById(R.id.tvGroup);
            holder.cbGroup = view.findViewById(R.id.cbGroup);
            view.setTag(holder);
        } else {
            view = convertView;
            holder = (GroupViewHolder) view.getTag();
        }
        final GetCartBean.DataBean dataBean = group.get(groupPosition);
        holder.tv.setText(dataBean.getSellerName());
        holder.cbGroup.setChecked(dataBean.isChecked());

        holder.cbGroup.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                //需要改变三个checkbox的状态值
                //1.一级列表的checkbox状态值
                dataBean.setChecked(holder.cbGroup.isChecked());
                //2.二级列表的checkbox状态值
                setChildrenCb(groupPosition, holder.cbGroup.isChecked());
                //3.全选的checkbox状态值
                ((CarActivity) context).setAllChecked(isAllGroupCbChecked());
                //计算钱和数量并显示
                setPriceAndCount();
                //刷新界面
                notifyDataSetChanged();
            }
        });
        return view;
    }

    @Override
    public View getChildView(final int groupPosition, final int childPosition, boolean isLastChild, final View convertView, ViewGroup parent) {
        View view;
        final ChildViewHolder holder;
        if (convertView == null) {
            view = inflater.inflate(R.layout.elv_child, null);
            holder = new ChildViewHolder();
            holder.iv = view.findViewById(R.id.iv);
            holder.tvTitle = view.findViewById(R.id.tvTitle);
            holder.tvSubhead = view.findViewById(R.id.tvSubhead);
            holder.tvPrice = view.findViewById(R.id.tvPrice);
            holder.cbChild = view.findViewById(R.id.cbChild);
            holder.btDel = view.findViewById(R.id.btDel);
            holder.tvNum = view.findViewById(R.id.tvNum);
            holder.ivDel = view.findViewById(R.id.ivDel);
            holder.ivAdd = view.findViewById(R.id.ivAdd);
            view.setTag(holder);
        } else {
            view = convertView;
            holder = (ChildViewHolder) view.getTag();
        }

        final GetCartBean.DataBean.ListBean listBean = child.get(groupPosition).get(childPosition);
        String images = listBean.getImages();
        Glide.with(context).load(images.split("\\|")[0]).into(holder.iv);
        holder.tvTitle.setText(listBean.getTitle());
        holder.cbChild.setChecked(child.get(groupPosition).get(childPosition).isChecked());
        holder.tvSubhead.setText(listBean.getSubhead());
        holder.tvPrice.setText("￥"+listBean.getPrice());
        holder.tvNum.setText(listBean.getCount() + "");
        //给checkbox设置点击事件
        holder.cbChild.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                //需要改变三个checkbox的状态值
                //1.二级列表的checkbox状态值
                listBean.setChecked(holder.cbChild.isChecked());
                //2.一级列表的checkbox状态值
                group.get(groupPosition).setChecked(isAllChildCbChecked(groupPosition));
                //3.全选的checkbox状态值
                ((CarActivity) context).setAllChecked(isAllGroupCbChecked());
                //计算钱和数量并显示
                setPriceAndCount();
                //刷新界面
                notifyDataSetChanged();
            }
        });

        holder.ivAdd.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                //获取目前显示的值
                int count = listBean.getCount();
                count++;
                //改变JavaBean里的状态值
                listBean.setCount(count);
                //计算钱和数量并显示
                setPriceAndCount();
                //刷新列表
                notifyDataSetChanged();
            }
        });
        holder.ivDel.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                //获取目前显示的值
                int count = listBean.getCount();
                if (count <= 1) {
                    count = 1;
                } else {
                    count--;
                }
                //改变JavaBean里的状态值
                listBean.setCount(count);
                //计算钱和数量并显示
                setPriceAndCount();
                //刷新列表
                notifyDataSetChanged();
            }
        });
        holder.btDel.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                //其实就是删除集合
                List listBeans = child.get(groupPosition);
                if (listBeans.size() > 0) {
                    listBeans.remove(childPosition);
                }
                if (listBeans.size() == 0) {
                    child.remove(groupPosition);
                    group.remove(groupPosition);
                }
                //计算钱和数量并显示
                setPriceAndCount();
                //改变全选状态
                ((CarActivity) context).setAllChecked(isAllGroupCbChecked());
                //刷新列表
                notifyDataSetChanged();
            }
        });
        return view;
    }

    @Override
    public boolean isChildSelectable(int groupPosition, int childPosition) {
        return false;
    }

    class GroupViewHolder {
        TextView tv;
        CheckBox cbGroup;
    }

    class ChildViewHolder {
        ImageView iv;
        TextView tvTitle;
        TextView tvSubhead;
        TextView tvPrice;
        CheckBox cbChild;
        Button btDel;
        TextView tvNum;
        ImageView ivDel;
        ImageView ivAdd;
    }

    /**
     * 设置一级列表对应的二级列表checkbox状态
     *
     * @param groupPosition
     * @param bool
     */
    private void setChildrenCb(int groupPosition, boolean bool) {
        List listBeans = child.get(groupPosition);
        for (int i = 0; i < listBeans.size(); i++) {
            listBeans.get(i).setChecked(bool);
        }
    }
    /**
     * 判断一级列表checkbox状态
     *
     * @return
     */
    private boolean isAllGroupCbChecked() {
        if (group.size() == 0) {
            return false;
        }
        for (int i = 0; i < group.size(); i++) {
            if (!group.get(i).isChecked()) {
                return false;
            }
        }
        return true;
    }
    /**
     * 判断二级列表checkbox状态
     *
     * @return
     */
    private boolean isAllChildCbChecked(int groupPosition) {
        List listBeans = child.get(groupPosition);
        for (int i = 0; i < listBeans.size(); i++) {
            if (!listBeans.get(i).isChecked()) {
                return false;
            }
        }
        return true;
    }
    /**
     * 设置钱和数量
     */
    private void setPriceAndCount() {
        ((CarActivity) context).setPriceAndCount(compute());
    }
    /**
     * 计算钱和数量
     */
    private PriceAndCount compute() {
        double price = 0;
        int count = 0;
        for (int i = 0; i < group.size(); i++) {
            List listBeans = child.get(i);
            for (int j = 0; j < listBeans.size(); j++) {
                if (listBeans.get(j).isChecked()) {
                    price += listBeans.get(j).getPrice() * listBeans.get(j).getCount();
                    count += listBeans.get(j).getCount();
                }
            }
        }
        return new PriceAndCount(price, count);
    }
    /**
     * 全选或者全不选
     *
     * @param bool
     */
    public void AllOrNone(boolean bool) {
        for (int i = 0; i < group.size(); i++) {
            group.get(i).setChecked(bool);
            setChildrenCb(i, bool);
        }
        setPriceAndCount();
        notifyDataSetChanged();
    }
}

 购物车的Activity

public class CarActivity extends AppCompatActivity implements CarView {

    private ImageView mBack;
    private LinearLayout mTopBar;
    private TextView mEdit;
    private ExpandableListView mElv;
    private CheckBox mCb;
    private TextView mTvTotal;
    private TextView mTvCount;
    private ElvAdapter elvAdapter;
    private CarPresenter mCarPresenter;
    private List mDataBeans;
    private List> mLists;
    private int mPid;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_car);
        mPid = getIntent().getIntExtra("pid", 1);
        initView();
    }

    private void initView() {
        mBack = (ImageView) findViewById(R.id.back);
        mEdit = (TextView) findViewById(R.id.edit);
        mTopBar = (LinearLayout) findViewById(R.id.top_bar);
        mElv = (ExpandableListView) findViewById(R.id.elv);
        mCb = (CheckBox) findViewById(R.id.cb);
        mTvTotal = (TextView) findViewById(R.id.tvTotal);
        mTvCount = (TextView) findViewById(R.id.tvCount);
        mCarPresenter = new CarPresenter(this);
        mCarPresenter.carDatas(mDataBeans,mLists,mPid);
    }


    @Override
    public void onCarSuccess(List group, List> child) {
        mDataBeans = group;
        mLists = child;
        for (int i = 0; i < group.size(); i++) {
            List list = group.get(i).getList();
            if (list.size() == 0) {
                group.remove(i);
                child.remove(i);
            }
        }
        elvAdapter = new ElvAdapter(this,group,child);
        mElv.setGroupIndicator(null);
        mElv.setAdapter(elvAdapter);
        for (int i = 0; i < group.size(); i++) {
            mElv.expandGroup(i);
        }
    }

    @Override
    public void onCarFailed(String error) {

    }

    public void setPriceAndCount(PriceAndCount priceAndCount) {
        mTvTotal.setText("合计："+"￥" + priceAndCount.getPrice());
        mTvCount.setText("去结算(" + priceAndCount.getCount() + ")");
    }
    public void setAllChecked(boolean bool) {
        mCb.setChecked(bool);
    }
}

 布局文件

activity主布局

商家布局

 

商家子布局