电商项目中常常有购物车这个功能，做个很多项目了，都有不同的界面，选了一个来讲一下。
RecyclerView 模仿淘宝购物车功能(删除选择商品，商品计算，选择， 全选反选，商品数量加减等)
看看效果图：
Activity代码：
/***** * RecyclerView 模仿淘宝购物车功能 * * 删除选择商品，商品计算，选择，全选反选，商品数量加减等 * */public class MainActivity extends AppCompatActivity { private RecyclerView rvNestDemo; private CartAdapter cartAdapter; CartInfo cartInfo; double price; int num; TextView cartNum; TextView cartMoney; Button cartShoppMoular; CheckBox checkBox; private TextView btnDelete; @Override protected void onCreate(@Nullable Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); rvNestDemo = (RecyclerView) findViewById(R.id.rv_nest_demo); cartNum = findViewById(R.id.cart_num); cartMoney = findViewById(R.id.cart_money); cartShoppMoular = findViewById(R.id.cart_shopp_moular); cartShoppMoular.setOnClickListener(new OnClickListener()); checkBox = findViewById(R.id.cbx_quanx_check); checkBox.setOnClickListener(new OnClickListener()); btnDelete = (TextView) findViewById(R.id.btn_delete); initView(); } private void initView() { btnDelete.setOnClickListener(new OnClickListener()); showData(); rvNestDemo.setLayoutManager(new LinearLayoutManager(this)); DividerItemDecoration itemDecoration = new DividerItemDecoration(this, DividerItemDecoration.VERTICAL); itemDecoration.setDrawable(ContextCompat.getDrawable(this, R.drawable.line_divider_inset)); rvNestDemo.addItemDecoration(itemDecoration); cartAdapter = new CartAdapter(this, cartInfo.getData()); rvNestDemo.setAdapter(cartAdapter); showExpandData(); } private void showExpandData() { /** * 全选 */ cartAdapter.setOnItemClickListener(new OnViewItemClickListener() { @Override public void onItemClick(boolean isFlang, View view, int position) { cartInfo.getData().get(position).setIscheck(isFlang); int length = cartInfo.getData().get(position).getItems().size(); for (int i = 0; i < length; i++) { cartInfo.getData().get(position).getItems().get(i).setIscheck(isFlang); } cartAdapter.notifyDataSetChanged(); showCommodityCalculation(); } }); /** * 计算价钱 */ cartAdapter.setOnItemMoneyClickListener(new OnItemMoneyClickListener() { @Override public void onItemClick(View view, int position) { showCommodityCalculation(); } }); } /*** * 计算商品的数量和价格 */ private void showCommodityCalculation() { price = 0; num = 0; for (int i = 0; i < cartInfo.getData().size(); i++) { for (int j = 0; j < cartInfo.getData().get(i).getItems().size(); j++) { if (cartInfo.getData().get(i).getItems().get(j).ischeck()) { price += Double.valueOf((cartInfo.getData().get(i).getItems().get(j).getNum() * Double.valueOf(cartInfo.getData().get(i).getItems().get(j).getPrice()))); num++; } else { checkBox.setChecked(false); } } } if (price == 0.0) { cartNum.setText("共0件商品"); cartMoney.setText("¥ 0.0"); return; } try { String money = String.valueOf(price); cartNum.setText("共" + num + "件商品"); if (money.substring(money.indexOf("."), money.length()).length() > 2) { cartMoney.setText("¥ " + money.substring(0, (money.indexOf(".") + 3))); return; } cartMoney.setText("¥ " + money.substring(0, (money.indexOf(".") + 2))); } catch (Exception e) { e.printStackTrace(); } } private void showData() { cartInfo = JSON.parseObject(JSONDATA(), CartInfo.class); } private class OnClickListener implements View.OnClickListener { @Override public void onClick(View v) { switch (v.getId()) { //全选和不全选 case R.id.cbx_quanx_check: if (checkBox.isChecked()) { int length = cartInfo.getData().size(); for (int i = 0; i < length; i++) { cartInfo.getData().get(i).setIscheck(true); int lengthn = cartInfo.getData().get(i).getItems().size(); for (int j = 0; j < lengthn; j++) { cartInfo.getData().get(i).getItems().get(j).setIscheck(true); } } } else { int length = cartInfo.getData().size(); for (int i = 0; i < length; i++) { cartInfo.getData().get(i).setIscheck(false); int lengthn = cartInfo.getData().get(i).getItems().size(); for (int j = 0; j < lengthn; j++) { cartInfo.getData().get(i).getItems().get(j).setIscheck(false); } } } cartAdapter.notifyDataSetChanged(); showCommodityCalculation(); break; case R.id.btn_delete: //删除选中商品 cartAdapter.removeChecked(); showCommodityCalculation(); break; case R.id.cart_shopp_moular: Toast.makeText(MainActivity.this,"提交订单: "+cartMoney.getText().toString()+"元",Toast.LENGTH_LONG).show(); break; } }} 这是我写的第二个购物车，基本的功能都有了的。
有需要的小伙们，可以参考一下。