接上文，已经实现了，GreenDao的导入，与创建开发需求所需要的数据类，以及自动生成相关的类。
接下来，就是数据库的操作。
首先，我们拿到数据库的操作对象，此处我选择的是在application中，可根据自己的需求自行选择。
/**
* 获取本地数据库操作对象
*/
public CashierGoodsEntityDao getCashierGoodsEntityDao() {
DaoMaster.DevOpenHelper helper = new DaoMaster.DevOpenHelper(context, "cashier_goods_entity");
Database db = helper.getWritableDb();
DaoSession mDaoSession = new DaoMaster(db).newSession();
CashierGoodsEntityDao cashierGoodsEntityDao = mDaoSession.getCashierGoodsEntityDao();
return cashierGoodsEntityDao;
}
上述代码，兑换为自己的相应的类即可，拿到的 CashierGoodsEntityDao就可以进行一系列的数据的操作。
/**
* 本地购物车的初始化
*/
public void setDbData() {
cashierGoodsEntityDao = App.getInstance().getCashierGoodsEntityDao();
cashierGoodsEntities = new ArrayList<>();
cashierGoodsEntities.addAll(cashierGoodsEntityDao.loadAll());//获取所有的购物车数据
}
/**
* 新增或者更新原有数据
*/
public void insertData() {
entity = (CashierGoodsEntity) getIntent().getSerializableExtra("entity");
if (entity == null || cashierGoodsEntities == null) {
return;
}
if (cashierGoodsEntities.size() == 0) {
cashierGoodsEntityDao.insert(entity);
} else {
for (CashierGoodsEntity cashEntity : cashierGoodsEntities) {
if (cashEntity.getGoodsId().equals(entity.getGoodsId())) {
int tempNumber = cashEntity.getNumber();
cashEntity.setNumber(tempNumber + 1);
cashierGoodsEntityDao.update(cashEntity);
addNewData = false;
}
}
if (addNewData) {
cashierGoodsEntityDao.insert(entity);
}
}
cashierGoodsEntities.clear();
cashierGoodsEntities.addAll(cashierGoodsEntityDao.loadAll());//获取所有的购物车数据
adapterCashier = new AdapterCashier(this, R.layout.item_cashier_buy_product_layout, cashierGoodsEntities,this::setNumChange);
recyclerViewShop.setLayoutManager(new LinearLayoutManager(this));
recyclerViewShop.setAdapter(adapterCashier);
View headView = LayoutInflater.from(this).inflate(R.layout.cashier_head_layout_for_clear_layout, null);
adapterCashier.addHeaderView(headView);
TextView textViewDelete = headView.findViewById(R.id.tvForClear);
textViewDelete.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
clearAllShopData(true, "");
}
});
adapterCashier.setOnItemLongClickListener(new BaseQuickAdapter.OnItemLongClickListener() {
@Override
public boolean onItemLongClick(BaseQuickAdapter adapter, View view, int position) {
CommDialog.newInstance(screen).setClickListen(new CommDialog.TwoSelDialog() {
@Override
public void leftClick() {
}
@Override
public void rightClick() {
//确定
clearAllShopData(false, cashierGoodsEntities.get(position).getGoodsId());
}
}).setTitle("删除商品").setContent("是否删除商品").show();
return false;
}
});
}
/**
* 清除所有数据，结算或者点击清空数据时调用
* 清空就清空当前所有数据，并且退出页面
* 删除时 需要刷新数据
*/
public void clearAllShopData(boolean clearAll, String deleteId) {
if (clearAll) {
cashierGoodsEntityDao.deleteAll();
finish();
return;
}
if (StringUtil.isNull(deleteId)) {
return;
}
for (CashierGoodsEntity cashEntity : cashierGoodsEntities) {
if (cashEntity.getGoodsId().equals(deleteId)) {
cashierGoodsEntityDao.delete(cashEntity);
}
}
cashierGoodsEntities.clear();
cashierGoodsEntities.addAll(cashierGoodsEntityDao.loadAll());//获取所有的购物车数据
if (cashierGoodsEntities.size() == 0) {
finish();
}else {
adapterCashier.setNewData(cashierGoodsEntities);
}
}
@Override
public void setNumChange(int number, String goodsId) {
for (int i = 0; i < cashierGoodsEntities.size(); i++) {
if (cashierGoodsEntities.get(i).getGoodsId().equals(goodsId)) {
if (number == 0) {
clearAllShopData(false, goodsId);
break;
} else {
cashierGoodsEntities.get(i).setNumber(number);
cashierGoodsEntityDao.update(cashierGoodsEntities.get(i));
cashierGoodsEntities.clear();
cashierGoodsEntities.addAll(cashierGoodsEntityDao.loadAll());//获取所有的购物车数据
adapterCashier.setNewData(cashierGoodsEntities);
break;
}
}
}
}
以下是购物车列表的 ，适配器中的代码：
public class AdapterCashier extends BaseQuickAdapter<CashierGoodsEntity, BaseViewHolder> implements View.OnClickListener,
EditDialogBuyProduct.dialogDoSure{
private Context context;
private int number;
private String goodsId;
private ItemChange listener;
private int stock;//库存
private int position;
private TextView textViewNumber;
public AdapterCashier(Context context, int layoutResId, @Nullable List<CashierGoodsEntity> data, ItemChange listener) {
super(layoutResId, data);
this.context = context;
this.listener = listener;
}
@Override
protected void convert(BaseViewHolder helper, CashierGoodsEntity item) {
StringUtil.setCommontTextShow(helper.getView(R.id.tvItemProductName), item.getName());
StringUtil.setCommontTextShow(helper.getView(R.id.tvItemProductStock), "当前库存为：" + item.getStockNumber());
StringUtil.setTextViewShowProductPrice(item.getPrice(), helper.getView(R.id.tvItemProductPrice), true);
GlideTools.setImageShowImgNormal(context, item.getImgUrl(), helper.getView(R.id.ivItemProductImg));
StringUtil.setCommontTextShow(helper.getView(R.id.tvItemProductNumber), item.getNumber() + "");
TextView textViewAdd = helper.getView(R.id.tvItemProductAdd);
textViewNumber = helper.getView(R.id.tvItemProductNumber);
TextView textViewMinus = helper.getView(R.id.tvItemProductMinus);
textViewAdd.setTag(item);
textViewMinus.setTag(item);
textViewNumber.setTag(item);
textViewAdd.setOnClickListener(this::onClick);
textViewNumber.setOnClickListener(this::onClick);
textViewMinus.setOnClickListener(this::onClick);
}
@Override
public void onClick(View view) {
if (view.getTag() == null) {
App.showToast("tag为空");
return;
}
CashierGoodsEntity entity = (CashierGoodsEntity) view.getTag();
goodsId = entity.getGoodsId();
stock = StringUtil.StringToInt(entity.getStockNumber());
number = entity.getNumber();
switch (view.getId()) {
case R.id.tvItemProductAdd:
if (number >= stock) {
App.showToast("库存数为：" + stock);
return;
}
number++;
entity.setNumber(number);
listener.setNumChange(number, goodsId);
break;
case R.id.tvItemProductNumber:
EditDialogBuyProduct editDialog = new EditDialogBuyProduct(context, R.style.PXDialog,
this::whenPressSure, String.valueOf(number), goodsId);
editDialog.show();
break;
case R.id.tvItemProductMinus:
if (number >= 1) {
number--;
entity.setNumber(number);
listener.setNumChange(number, goodsId);
}
break;
}
}
@Override
public void onBindViewHolder(@NonNull BaseViewHolder holder, int position, @NonNull List<Object> payloads) {
super.onBindViewHolder(holder, position, payloads);
if (payloads.isEmpty()) {
onBindViewHolder(holder, position);
} else {
textViewNumber.setText(payloads.get(0) + "");
}
}
@Override
public void whenPressSure(String number, String goodsId) {
listener.setNumChange(StringUtil.StringToInt(number), goodsId);
}
public interface ItemChange {
void setNumChange(int number, String goodsId);
}
}
其中，数据的输入是点击弹出一个框，实现数据的输入，此处不再赘述，我觉得不是什么问题，大家可以根据自己的需求，自行修改，此处只是将我的代码贴出来，仅供参考。
这是我这一两天的工作成果，写出来分享给大家，希望可以对大家有所帮助。
重点来了，走过路过不要错过，支持一下，打赏一下，十块八块都是爱。