EventBus匯入依賴：compile 'org.greenrobot:eventbus:3.0.0'

//註冊EventBus

public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {

    view = inflater.inflate(R.layout.fragment_shopping, null);
    //註冊EventBus
EventBus.getDefault().register(this);
    initView();
    return 
 
view;
}

//訂閱方法，當接收到事件的時候，會呼叫該方法
//獲取價格
@Subscribe(threadMode = ThreadMode.MAIN)
public void onEvent(MoneyAndCount moneyAndCount) {
    //double型別保留2位小數點
DecimalFormat df = new DecimalFormat("######0.00");
    contprice.setText("總價:" + df.format(moneyAndCount.getPrice()));
    jiesuan.setText("結算(" + moneyAndCount.getCount() + ")"
 
);
}

//解除註冊

@Override
public void onDestroy() {
    super.onDestroy();
    //解除註冊
EventBus.getDefault().unregister(this);
}

二級列表介面卡：

private List<CheckShoppingCardBean.DataBean> grouplist;
private List<List<CheckShoppingCardBean.DataBean.ListBean>> childlist;
private Context context;
private double 
 
money;
private int counts;

public MExpandlbAdapter(List<CheckShoppingCardBean.DataBean> grouplist, List<List<CheckShoppingCardBean.DataBean.ListBean>> childlist, Context context) {
    this.grouplist = grouplist;
    this.childlist = childlist;
    this.context = context;
}

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

@Override
public int getChildrenCount(int i) {
    return childlist.get(i).size();
}

@Override
public Object getGroup(int i) {
    return grouplist.get(i);
}

@Override
public Object getChild(int i, int i1) {
    return childlist.get(i1);
}

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

@Override
public long getChildId(int i, int i1) {
    return i1;
}

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

@Override
public View getGroupView(final int i, boolean b, View view, ViewGroup viewGroup) {
    View view1;
    final V1 v1;
    if (view == null) {
        v1 = new V1();
        view1 = View.inflate(context, R.layout.cardshopsitem, null);
        v1.groupchecked = view1.findViewById(R.id.grouchecked);
        view1.setTag(v1);
    } else {
        view1 = view;
        v1 = (V1) view1.getTag();
    }

    v1.groupchecked.setChecked(grouplist.get(i).isGroupChecked());
    v1.groupchecked.setText(grouplist.get(i).getSellerName());


    //父列表點選選中，然後選中所有子列表
v1.groupchecked.setOnClickListener(new View.OnClickListener() {
        @Override
public void onClick(View view) {
            if (v1.groupchecked.isChecked()) {
                grouplist.get(i).setGroupChecked(v1.groupchecked.isChecked());
                isGroupAllChild(v1.groupchecked.isChecked(), i);
                //父列表點選全選中，然後全選
boolean all = isAll();
                Log.e("All", all + "");
                if (all) {
                    Toast.makeText(context, "全選", Toast.LENGTH_SHORT).show();
                    EventBus.getDefault().post(new All(v1.groupchecked.isChecked()));
                }

                //計算價格總和，和數量總和
allPriceAndCount();

            } else {
                grouplist.get(i).setGroupChecked(v1.groupchecked.isChecked());
                isGroupAllChild(v1.groupchecked.isChecked(), i);
                EventBus.getDefault().post(new All(v1.groupchecked.isChecked()));

                //計算價格總和，和數量總和
allPriceAndCount();
            }

        }
    });

    return view1;

}

@Override
public View getChildView(final int i, final int i1, boolean b, View view, ViewGroup viewGroup) {
    View view1;
    final V2 v2;
    if (view == null) {
        v2 = new V2();
        view1 = View.inflate(context, R.layout.goodsitem, null);
        v2.childchecked = view1.findViewById(R.id.childchecked);
        v2.goodsimg = view1.findViewById(R.id.goodsimg);
        v2.titles = view1.findViewById(R.id.titles);
        v2.price = view1.findViewById(R.id.price);
        v2.numjiajia = view1.findViewById(R.id.numjiajia);
        v2.numjianjian = view1.findViewById(R.id.numjianjian);
        v2.num = view1.findViewById(R.id.num);
        view1.setTag(v2);
    } else {
        view1 = view;
        v2 = (V2) view1.getTag();
    }

    ImageLoader instance = ImageLoader.getInstance();
    v2.childchecked.setChecked(childlist.get(i).get(i1).ischildckecked());
    instance.displayImage(childlist.get(i).get(i1).getImages().split("\\|")[0], v2.goodsimg);
    v2.titles.setText(childlist.get(i).get(i1).getTitle());
    v2.price.setText(childlist.get(i).get(i1).getPrice() + "");
    v2.num.setText(childlist.get(i).get(i1).getNum() + "");


    //數量加加減減監聽
v2.numjiajia.setOnClickListener(new View.OnClickListener() {
        @Override
public void onClick(View view) {
            int num = childlist.get(i).get(i1).getNum();
            if (num < 9) {
                childlist.get(i).get(i1).setNum(num + 1);
                notifyDataSetChanged();
                //計算價格總和，和數量總和
allPriceAndCount();
            } else {
                Toast.makeText(context, "數量以到達商品庫存上線", Toast.LENGTH_SHORT).show();
            }

        }
    });

    v2.numjianjian.setOnClickListener(new View.OnClickListener() {
        @Override
public void onClick(View view) {
            int num = childlist.get(i).get(i1).getNum();
            if (num > 1) {
                childlist.get(i).get(i1).setNum(num - 1);
                notifyDataSetChanged();
                //計算價格總和，和數量總和
allPriceAndCount();
            } else {
                Toast.makeText(context, "商品數量已經是1了", Toast.LENGTH_SHORT).show();
            }

        }
    });


    //子列表點選選中，判斷子列表是否都選中，然後選中父列表
v2.childchecked.setOnClickListener(new View.OnClickListener() {
        @Override
public void onClick(View view) {
            if (v2.childchecked.isChecked()) {
                childlist.get(i).get(i1).setIschildckecked(v2.childchecked.isChecked());
                boolean childChecked = isChildChecked(i);
                if (childChecked) {
                    grouplist.get(i).setGroupChecked(v2.childchecked.isChecked());
                }
                //重新整理介面卡
notifyDataSetChanged();
                boolean all = isAll();
                Log.e("All", all + "");
                if (all) {
                    Toast.makeText(context, "全選", Toast.LENGTH_SHORT).show();
                    EventBus.getDefault().post(new All(v2.childchecked.isChecked()));
                }
                //計算價格總和，和數量總和
allPriceAndCount();

            } else {
                childlist.get(i).get(i1).setIschildckecked(v2.childchecked.isChecked());
                grouplist.get(i).setGroupChecked(v2.childchecked.isChecked());
                //重新整理介面卡
notifyDataSetChanged();
                EventBus.getDefault().post(new All(v2.childchecked.isChecked()));

                //計算價格總和，和數量總和
allPriceAndCount();
            }
        }
    });
    return view1;
}

@Override
public boolean isChildSelectable(int i, int i1) {
    return true;
}


//優化類
class V1 {
    CheckBox groupchecked;
}

class V2 {
    CheckBox childchecked;
    ImageView goodsimg;
    TextView titles;
    TextView price;
    TextView numjianjian;
    TextView num;
    TextView numjiajia;
}


/***
 * 子列表點選選中，判斷子列表是否都選中，然後選中父列表
 */
public boolean isChildChecked(int positon) {
    List<CheckShoppingCardBean.DataBean.ListBean> listBeen = childlist.get(positon);
    for (int i = 0; i < listBeen.size(); i++) {
        if (!listBeen.get(i).ischildckecked()) {
            return false;
        }
    }

    return true;
}

/***
 * 父列表點選選中，然後選中所有子列表
 */
public void isGroupAllChild(boolean b, int positon) {
    List<CheckShoppingCardBean.DataBean.ListBean> listBeen = childlist.get(positon);
    if (b) {
        for (int i = 0; i < listBeen.size(); i++) {
            listBeen.get(i).setIschildckecked(b);
        }
    } else {
        for (int i = 0; i < listBeen.size(); i++) {
            listBeen.get(i).setIschildckecked(b);
        }
    }

    notifyDataSetChanged();

}

/***
 * 父列表點選全選中，然後全選
 */
public boolean isAll() {
    for (int i = 0; i < grouplist.size(); i++) {
        if (!grouplist.get(i).isGroupChecked()) {
            return false;
        }
    }
    return true;
}

/***
 * 點選全選父列表，子列表全選
 */
public void setAll(boolean b) {
    for (int i = 0; i < grouplist.size(); i++) {
        grouplist.get(i).setGroupChecked(b);
    }
    for (int i = 0; i < childlist.size(); i++) {
        List<CheckShoppingCardBean.DataBean.ListBean> listBeen = childlist.get(i);
        for (int j = 0; j < listBeen.size(); j++) {
            listBeen.get(j).setIschildckecked(b);
        }
    }
    //重新整理介面卡
notifyDataSetChanged();

    //計算價格總和，和數量總和
allPriceAndCount();

}

/***
 * 計算價格總和，和數量總和
 */
public void allPriceAndCount() {
    money = 0;
    counts = 0;
    for (int i = 0; i < childlist.size(); i++) {
        List<CheckShoppingCardBean.DataBean.ListBean> listBeen = childlist.get(i);
        for (int j = 0; j < listBeen.size(); j++) {
            if (listBeen.get(j).ischildckecked()) {
                money += listBeen.get(j).getPrice() * listBeen.get(j).getNum();
                counts += listBeen.get(j).getNum();
            }
        }

    }
    //傳送價格數量進行顯示
EventBus.getDefault().post(new MoneyAndCount(money, counts));
}