Question

我已经在我的应用程序中编辑了文本来操纵产品数量，但是如果我要更改数量的问题，那时候会获得NPE。要更改编辑文本中的数量，我需要删除现有文本并需要添加一个新文本，请检查以下代码

viewHolder.edt_product_qty.addTextChangedListener(new TextWatcher() {
                @Override
                public void beforeTextChanged(CharSequence charSequence, int i, int i1, int i2) {

                }

                @Override
                public void onTextChanged(CharSequence charSequence, int i, int i1, int i2) {


                    quantity_count= Integer.parseInt(viewHolder.edt_product_qty.getText().toString());


                    buyNowList(user_id,"UserCart",0,stList.get(position).getCartList1().getId(),stList.get(position).getCartList1().getProdSku(),stList.get(position).getCartList1().getProdId(),quantity_count,0,qty_status,stList.get(position).getCartList1().getProdPrice());

                }

                @Override
                public void afterTextChanged(Editable editable) {

                }
            });

Answer 1

使用try和catch块

try {
  quantity_count = Integer.parseInt(viewHolder.edt_product_qty.getText().toString());
  buyNowList(user_id,"UserCart",0,stList.get(position).getCartList1().getId(),stList.get(position).getCartList1().getProdSku(),stList.get(position).getCartList1().getProdId(),quantity_count,0,qty_status,stList.get(position).getCartList1().getProdPrice());
} catch (NumberformatException e) {
  e.printStackTrace();
}

Answer 2

当您删除editText上的所有内容时，editText将返回一个空字符串。因此，您将获得NPE和Number Format Exception。

您可以这样处理：

if(!viewHolder.edt_product_qty.getText().toString().equals("")){
   quantity_count= Integer.parseInt(viewHolder.edt_product_qty.getText().toString()); 
   buyNowList(user_id,"UserCart",0,stList.get(position).getCartList1().getId(),stList.get(position).getCartList1().getProdSku(),stList.get(position).getCartList1().getProdId(),quantity_count,0,qty_status,stList.get(position).getCartList1().getProdPrice());
}

比较初始值和当前值

首先，您需要在beforeTextChanged中将变量分配为初始值。

initalValue =viewHolder.edt_product_qty.getText().toString();

然后在onTextChanged中输入

：

if(!viewHolder.edt_product_qty.getText().toString().equals("")){
    quantity_count = Integer.parseInt(viewHolder.edt_product_qty.getText().toString()); // 
}if(initalValue>quantity_count)
{
    // code
}else
{
    //code
}

看看这个https://stackoverflow.com/a/20278708/5156075

Answer 3

@Override
public void onTextChanged(CharSequence charSequence, int i, int i1, int i2) {
    try {
        quantity_count = Integer.parseInt(viewHolder.edt_product_qty.getText().toString()); 
        buyNowList(user_id, "UserCart", 0, stList.get(position).getCartList1().getId(), stList.get(position).getCartList1().getProdSku(), stList.get(position).getCartList1().getProdId(), quantity_count, 0, qty_status, stList.get(position).getCartList1().getProdPrice());    
    } catch (NumberFormatException e) {
        // maybe show some information to user in case of exception
    }
}

如何在edittext OntextChanged中处理数字格式异常

3 个答案: