android listview中checkbox（购物车，批量操作）-阿里云开发者社区

最近在做购物车这里。在做全选的时候总会出现getchillat（）空指针的问题，所以放弃了。
后来参考了网上的一些例子。
这篇：http://www.open-open.com/lib/view/open1343744786602.html 还算可以在适配器中把view放入map中。算是解决了一般的问题。
至于加入之后就可以看下面
check_goods_all和delete中的代码吧
这两个函数的最后都重新设置了适配器因为我在调用cartAdapter.notifyDataSetChanged()的时候没有变化，具体也不太清楚。但是却是好用。
因为某些原因不能提供整个项目源代码。
[java]view
 plaincopy

public class Shopping_cart_listActivity extends Activity {  

    private Intent intent;  

    private ListView listView;  

    private ArrayList<HashMap<String, Object>> listItem;  

    // private SimpleAdapter listAdapter;  

    private CartAdapter cartAdapter;  

    private CheckBox check_goods_all;  

    String[] goods_name = { "奶粉", "奶粉", "奶粉", "奶粉", "奶粉", "奶粉", "奶粉", "奶粉" };  

    int[] goods_number = { 1, 2, 3, 4, 5, 6, 7, 8 };  

    double[] goods_price = { 668.00, 668.00, 668.00, 668.00, 668.00, 668.00,  

            668.00, 668.00 };  

    public void init() {  

        intent = new Intent();  

        listView = (ListView) findViewById(R.id.ListView_shopping_cart_list);  

        check_goods_all = (CheckBox) findViewById(R.id.check_goods_all);  

        check_goods_all.setChecked(false);  

        // listAdapter = new SimpleAdapter(this, getData(),  

        cartAdapter = new CartAdapter(getData(), this.getApplicationContext());  

        listView.setAdapter(cartAdapter);  

    }  

    public ArrayList<HashMap<String, Object>> getData() {  

        listItem = new ArrayList<HashMap<String, Object>>();  

        for (int i = 0; i < 8; i++) {  

            HashMap<String, Object> map = new HashMap<String, Object>();  

            map.put("goods_info", goods_name[i]);  

            map.put("shopping_cart_each_count", goods_number[i]);  

            map.put("shopping_cart_each_price", goods_price[i]);  

            // map.put("check_goods", false);  

            listItem.add(map);  

        }  

        return listItem;  

    }  

    @Override  

    protected void onCreate(Bundle savedInstanceState) {  

        super.onCreate(savedInstanceState);  

        setContentView(R.layout.activity_shopping_cart_list);  

        init();  

    }  

    @Override  

    public boolean onCreateOptionsMenu(Menu menu) {  

        // Inflate the menu; this adds items to the action bar if it is present.  

        getMenuInflater().inflate(R.menu.activity_shopping_cart_list1, menu);  

        return true;  

    }  

    public void check_goods_all(View v) {  

        /* 

         * for (int i = 0; i < listView.getCount(); i++) { 

         * cartAdapter.getIsSelected().put(i, check_goods_all.isChecked()); } 

         */  

        for (int i = 0; i < cartAdapter.getCount(); i++) {  

            cartAdapter.isSelected.set(i, check_goods_all.isChecked());  

        }  

        listView.setAdapter(cartAdapter);  

    }  

    public void delete(View v) {  

        int num = cartAdapter.isSelected.size();  

        ArrayList<Boolean> temp_isSelected = new ArrayList<Boolean>();  

        ArrayList<HashMap<String, Object>> temp_listItem = new ArrayList<HashMap<String,Object>>();  

        int j = 0;  

        for (int i = 0; i < num; i++) {  

            if (!cartAdapter.isSelected.get(i)) {  

                temp_isSelected.add(j, false);  

                temp_listItem.add(j++, cartAdapter.list.get(i));  

            }  

        }  

        cartAdapter.setIsSelected(temp_isSelected);  

        cartAdapter.setList(temp_listItem);  

        listView.setAdapter(cartAdapter);  

        System.out.println("适配器中剩余:" + listItem.size());  

        /* 

         * for (int i = 0; i < listView.getCount(); i++) { RelativeLayout ll = 

         * (RelativeLayout) listView.getChildAt(i);// 获得子级 CheckBox chkone = 

         * (CheckBox) ll.findViewById(R.id.check_goods);// 从子级中获得控件 if 

         * (chkone.isChecked()) { System.out.println(i + "------->"); 

         * listItem.remove(i); listAdapter.notifyDataSetChanged(); } } 

         */  

    }  

    public void return_to_before(View v) {  

        intent.setClass(Shopping_cart_listActivity.this, FrameActivity.class);  

        startActivity(intent);  

        finish();  

    }  

    public void settle(View v) {  

        intent.setClass(Shopping_cart_listActivity.this,  

                BrandRankGoodsInfoActivity.class);  

        startActivity(intent);  

        finish();  

    }  

    class CartAdapter extends BaseAdapter {  

        // 保存listview item的状态  

        HashMap<Integer, View> map = new HashMap<Integer, View>();  

        // 填充数据的list  

        private ArrayList<HashMap<String, Object>> list;  

        // 用来控制CheckBox的选中状况  

        private ArrayList<Boolean> isSelected;  

        // 上下文  

        private Context context;  

        // 用来导入布局  

        private LayoutInflater inflater = null;  

        // 构造器  

        public CartAdapter(ArrayList<HashMap<String, Object>> list,  

                Context context) {  

            this.context = context;  

            this.list = list;  

            isSelected = new ArrayList<Boolean>();  

            // 初始化数据  

            initDate();  

        }  

        // 初始化isSelected的数据  

        private void initDate() {  

            for (int i = 0; i < list.size(); i++) {  

                isSelected.add(i, false);  

            }  

        }  

        @Override  

        public int getCount() {  

            return list.size();  

        }  

        @Override  

        public Object getItem(int position) {  

            return list.get(position);  

        }  

        @Override  

        public long getItemId(int position) {  

            return position;  

        }  

        @SuppressWarnings("unused")  

        @Override  

        public View getView(int position, View convertView, ViewGroup parent) {  

            View view;  

            ViewHolder holder = null;  

            if (map.get(position) == null) {  

                // 获得ViewHolder对象  

                // 导入布局并赋值给convertview  

                LayoutInflater mInflater = (LayoutInflater) context  

                        .getSystemService(Context.LAYOUT_INFLATER_SERVICE);  

                view = mInflater.inflate(R.layout.listview_shopping_cart, null);  

                holder = new ViewHolder();  

                holder.check_goods = (CheckBox) view  

                        .findViewById(R.id.check_goods);  

                holder.shopping_cart_each_count = (EditText) view  

                        .findViewById(R.id.shopping_cart_each_count);  

                holder.shopping_cart_each_price = (TextView) view  

                        .findViewById(R.id.shopping_cart_each_price);  

                holder.goods_info = (TextView) view  

                        .findViewById(R.id.goods_info);  

                final int p = position;  

                // 为view设置标签  

                // final boolean ischecked = holder.check_goods.isChecked();  

                holder.check_goods.setOnClickListener(new OnClickListener() {  

                    @Override  

                    public void onClick(View v) {  

                        // TODO Auto-generated method stub  

                        CheckBox cb = (CheckBox) v;  

                        isSelected.set(p, cb.isChecked());  

                        /* 

                         * holder.check_goods.toggle(); isSelected.put(position, 

                         * holder.check_goods.isChecked()); 

                         */  

                    }  

                });  

                view.setTag(holder);  

            } else {  

                // 取出holder  

                view = map.get(position);  

                holder = (ViewHolder) view.getTag();  

            }  

            // 设置list中TextView的显示  

            holder.goods_info.setText((String) list.get(position).get(  

                    "goods_info"));  

            holder.shopping_cart_each_price.setText(((Double) list  

                    .get(position).get("shopping_cart_each_price")).toString());  

            holder.shopping_cart_each_count.setText(((Integer) list.get(  

                    position).get("shopping_cart_each_count")).toString());  

            // 根据isSelected来设置checkbox的选中状况  

            holder.check_goods.setChecked(isSelected.get(position));  

            return view;  

        }  

        public void setList(ArrayList<HashMap<String, Object>> list) {  

            this.list = list;  

        }  

        public ArrayList<HashMap<String, Object>> getList() {  

            return list;  

        }  

        public ArrayList<Boolean> getIsSelected() {  

            return isSelected;  

        }  

        public void setIsSelected(ArrayList<Boolean> isSelected) {  

            this.isSelected = isSelected;  

        }  

    }  

    class ViewHolder {  

        public RelativeLayout linerlayout_shopping_cart;  

        public ListView ListView_shopping_cart_list;  

        public Button shopping_cart_reduce;  

        public Button shopping_cart_add;  

        public EditText shopping_cart_each_count;  

        public TextView shopping_cart_each_price;  

        public TextView goods_info;  

        public CheckBox check_goods;  

    }  

}