Android实现购物车逻辑

//1.先创建eventbusevent包；2.创建MessageEvent类；3.创建PriceAndCountEvent类，用来存储价格和数量

public class MessageEvent {    private boolean checked;    public boolean isChecked(){        return checked;    };    public void setChecked(boolean checked){        this.checked = checked;    }}

public class PriceAndCountEvent {    private int price;    private int count;    public int getPrice() {        return price;    }    public void setPrice(int price) {        this.price = price;    }    public int getCount() {        return count;    }    public void setCount(int count) {        this.count = count;    }}
//购物车页面
public class Fragment4 extends Fragment implements IFragment4 {    private View view;    private ExpandableListView mElv;    private CheckBox mCb1;    private TextView mPrice;    Fragment4Adapter adapter;    /**     * 去结算     */    private TextView mJiesuan;    int count;    int price;    @Nullable    @Override    public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {        View view = inflater.inflate(R.layout.fragment4, null);        initView(view);        new Fragment4Presenter(this).getGoods();        EventBus.getDefault().register(this);        return view;    }    private void initView(View view) {        mElv = (ExpandableListView) view.findViewById(R.id.elv);        mCb1 = (CheckBox) view.findViewById(R.id.cb1);        mPrice = (TextView) view.findViewById(R.id.price);        mJiesuan = (TextView) view.findViewById(R.id.jiesuan);        mCb1.setOnClickListener(new View.OnClickListener() {            @Override            public void onClick(View v) {                adapter.changeAllListCbState(mCb1.isChecked());            }        });    }    @Override    public void onDestroy() {        super.onDestroy();        EventBus.getDefault().unregister(this);    }    @Override    public void showList(List<GoosBean.DataBean> groupList, List<List<GoosBean.DataBean.DatasBean>> childList) {        adapter = new Fragment4Adapter(getActivity(), groupList, childList);        mElv.setAdapter(adapter);        mElv.setGroupIndicator(null);        //默认让其全部展开        for (int i = 0; i < groupList.size(); i++) {            mElv.expandGroup(i);        }    }    @Subscribe    public void onMessageEvent(MessageEvent event){        mCb1.setChecked(event.isChecked());    }    @Subscribe    public void onMessageEvent(PriceAndCountEvent event) {        mJiesuan.setText("结算(" + event.getCount() + ")");        mPrice.setText(event.getPrice() + "");    }}
//二级列表适配器
public class Fragment4Adapter extends BaseExpandableListAdapter {    private Context context;    private List<GoosBean.DataBean> grouplist;    private List<List<GoosBean.DataBean.DatasBean>> childlist;    private LayoutInflater inflater;    private IFragment4 iFragment4;    public Fragment4Adapter(Context context, List<GoosBean.DataBean> grouplist, List<List<GoosBean.DataBean.DatasBean>> childlist) {        this.context = context;        this.grouplist = grouplist;        this.childlist = childlist;        inflater = LayoutInflater.from(context);    }    @Override    public int getGroupCount() {        return grouplist.size();    }    @Override    public int getChildrenCount(int groupPosition) {        return childlist.get(groupPosition).size();    }    @Override    public Object getGroup(int groupPosition) {        return grouplist.get(groupPosition);    }    @Override    public Object getChild(int groupPosition, int childPosition) {        return childlist.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) {        final GroupViewHolder holder;        if (convertView == null){            holder = new GroupViewHolder();            convertView = inflater.inflate(R.layout.item_parent,null);            holder.cbGroup = (CheckBox) convertView.findViewById(R.id.cb_parent);            holder.tv_number = (TextView) convertView.findViewById(R.id.tv_number);            convertView.setTag(holder);        } else {            holder = (GroupViewHolder) convertView.getTag();        }        final GoosBean.DataBean dataBean = grouplist.get(groupPosition);        holder.cbGroup.setChecked(dataBean.isChecked());        holder.tv_number.setText(dataBean.getTitle());        holder.cbGroup.setOnClickListener(new View.OnClickListener() {            @Override            public void onClick(View v) {                dataBean.setChecked(holder.cbGroup.isChecked());                changeChildCbState(groupPosition,holder.cbGroup.isChecked());                EventBus.getDefault().post(computer());                changeAllCbState(isAllGroupCbSelected());                notifyDataSetChanged();            }        });        return convertView;    }    @Override    public View getChildView(final int groupPosition, final int childPosition, boolean isLastChild, View convertView, ViewGroup parent) {        final ChildViewHolder holder;        if (convertView == null){            holder = new ChildViewHolder();            convertView = inflater.inflate(R.layout.item_child,null);            holder.cbChild = (CheckBox) convertView.findViewById(R.id.cb_child);            holder.tv_tel = (TextView) convertView.findViewById(R.id.tv_tel);            holder.tv_content = (TextView) convertView.findViewById(R.id.tv_content);            holder.tv_time = (TextView) convertView.findViewById(R.id.tv_time);            holder.tv_pri = (TextView) convertView.findViewById(R.id.tv_pri);            holder.jian = (TextView) convertView.findViewById(R.id.jian);            holder.num = (TextView) convertView.findViewById(R.id.num);            holder.jia = (TextView) convertView.findViewById(R.id.jia);            holder.del = (TextView) convertView.findViewById(R.id.del);            convertView.setTag(holder);        } else {            holder = (ChildViewHolder) convertView.getTag();        }        final GoosBean.DataBean.DatasBean datasBean = childlist.get(groupPosition).get(childPosition);        holder.cbChild.setChecked(datasBean.isChecked());        holder.tv_tel.setText(datasBean.getType_name());        holder.tv_content.setText(datasBean.getMsg());        holder.tv_time.setText(datasBean.getAdd_time());        holder.tv_pri.setText(datasBean.getPrice()+"");        //给二级CheckBox设置点击事件        holder.cbChild.setOnClickListener(new View.OnClickListener() {            @Override            public void onClick(View v) {                //设置该条目对象里面的CheckBox属性值                datasBean.setChecked(holder.cbChild.isChecked());                EventBus.getDefault().post(computer());                if (holder.cbChild.isChecked()){                    //当前CheckBox是选中状态                    if (isAllChildCbSelected(groupPosition)){                        changeGroupCbState(groupPosition,true);                        changeAllCbState(isAllGroupCbSelected());                    }                } else {                    //取消选中                    changeGroupCbState(groupPosition,false);                    changeAllCbState(isAllGroupCbSelected());                }                notifyDataSetChanged();            }        });        //加号-数量加        holder.jia.setOnClickListener(new View.OnClickListener() {            @Override            public void onClick(View v) {                int num = datasBean.getNum();                holder.num.setText(++num+"");                datasBean.setNum(num);                if (holder.cbChild.isChecked()){                    EventBus.getDefault().post(computer());                }            }        });        //减号-数量减        holder.jian.setOnClickListener(new View.OnClickListener() {            @Override            public void onClick(View v) {                int num = datasBean.getNum();                if (num==1){                    return;                }                holder.num.setText(--num+"");                datasBean.setNum(num);                if (holder.cbChild.isChecked()){                    EventBus.getDefault().post(computer());                }            }        });        //删除商品        holder.del.setOnClickListener(new View.OnClickListener() {            @Override            public void onClick(View v) {                List<GoosBean.DataBean.DatasBean> datasBeen = childlist.get(groupPosition);                GoosBean.DataBean.DatasBean remove = datasBeen.remove(childPosition);                if (datasBeen.size() == 0){                    childlist.remove(groupPosition);                    grouplist.remove(groupPosition);                }                EventBus.getDefault().post(computer());                notifyDataSetChanged();            }        });        return convertView;    }    class GroupViewHolder{        CheckBox cbGroup;        TextView tv_number;    }    class ChildViewHolder {        CheckBox cbChild;        TextView tv_tel;        TextView tv_content;        TextView tv_time;        TextView tv_pri;        TextView jian;        TextView num;        TextView jia;        TextView del;    }    @Override    public boolean isChildSelectable(int groupPosition, int childPosition) {        return true;    }    //改变全选CheckBox状态    private void changeAllCbState(boolean flag){        MessageEvent messageEvent = new MessageEvent();        messageEvent.setChecked(flag);        EventBus.getDefault().post(messageEvent);    }    //改变二级列表CheckBox状态    private void changeChildCbState(int groupPosition,boolean flag){        List<GoosBean.DataBean.DatasBean> datasBeen = childlist.get(groupPosition);        for (int i = 0; i < datasBeen.size(); i++) {            GoosBean.DataBean.DatasBean datasBean = datasBeen.get(i);            datasBean.setChecked(flag);        }    }    //改变一级列表CheckBox状态    private void changeGroupCbState(int groupPosition,boolean flag){        GoosBean.DataBean dataBean = grouplist.get(groupPosition);        dataBean.setChecked(flag);    }    //判断一级列表是否全部选中    public boolean isAllGroupCbSelected(){        for (int i = 0; i < grouplist.size(); i++) {            GoosBean.DataBean dataBean = grouplist.get(i);            if (!dataBean.isChecked()){                return false;            }        }        return true;    }    //判断二级列表是否全部选中    public boolean isAllChildCbSelected(int groupPosition){        List<GoosBean.DataBean.DatasBean> datasBeen = childlist.get(groupPosition);        for (int i = 0; i < datasBeen.size(); i++) {            GoosBean.DataBean.DatasBean datasBean = datasBeen.get(i);            if (!datasBean.isChecked()){                return false;            }        }        return true;    }    //计算列表中选中的钱和数量    private PriceAndCountEvent computer(){        int count = 0;        int price = 0;        for (int i = 0; i < childlist.size(); i++) {            List<GoosBean.DataBean.DatasBean> datasBeen = childlist.get(i);            for (int j = 0; j < datasBeen.size(); j++) {                GoosBean.DataBean.DatasBean datasBean = datasBeen.get(j);                if (datasBean.isChecked()){                    count+=datasBean.getNum();                    price+=datasBean.getNum()*datasBean.getPrice();                }            }        }        PriceAndCountEvent priceAndCountEvent = new PriceAndCountEvent();        priceAndCountEvent.setCount(count);        priceAndCountEvent.setPrice(price);        return priceAndCountEvent;    }    //设置全选、反选    public void changeAllListCbState(boolean flag){        for (int i = 0; i < grouplist.size(); i++) {            changeGroupCbState(i,flag);            changeChildCbState(i,flag);        }        EventBus.getDefault().post(computer());        notifyDataSetChanged();    }}
//数据接口
public static final String url = "http://result.eolinker.com/iYXEPGn4e9c6dafce6e5cdd23287d2bb136ee7e9194d3e9?uri=evaluation";