Spinner OnItemSelectedListener Method in Android issue

Question

我的xml中有3个微调器。

1. one is Product Name
2. one is Product Quantity.
3. and 3rd one is Discount

现在，我

为每个调用单独的监听器..问题是我想使用项目数量来计算最终价格，并且我以相同的顺序调用微调器，即我写了名称，数量和折扣。

Quantity的侦听器终于被调用了，即使我在Discount Spinner上面写过。我不知道发生了什么..任何人都能面临这个问题吗...请帮助我..

这是我的微调侦听器：-

spnSelectItem.setOnItemSelectedListener(new OnItemSelectedListener() 
        {
            @Override
            public void onItemSelected(AdapterView<?> arg0, View arg1,
                    int arg2, long arg3)
            {
                strItem=spnSelectItem.getItemAtPosition(arg2).toString();           }
            @Override
            public void onNothingSelected(AdapterView<?> arg0) {
                // TODO Auto-generated method stub
            }
        });
          ///This method called last..
        spnQty.setOnItemSelectedListener(new OnItemSelectedListener() 
        {
            @Override
            public void onItemSelected(AdapterView<?> arg0, View arg1,int arg2, long arg3)
            {
                strQty=spnQty.getItemAtPosition(arg2).toString();
            @Override
            public void onNothingSelected(AdapterView<?> arg0) {
                // TODO Auto-generated method stub
            }
        });
     ///This method called before spnQty ..
     spnItemDiscount.setOnItemSelectedListener(new OnItemSelectedListener()
        {
            @Override
            public void onItemSelected(AdapterView<?> arg0, View arg1,int arg2, long arg3) 
            {
                disc=round(Double.parseDouble(spnItemDiscount.getItemAtPosition(arg2).toString().replace("%", "")));
            }
            @Override
            public void onNothingSelected(AdapterView<?> arg0) {
                // TODO Auto-generated method stub
            }
        });

Answer 1

为什么不创建一个单独的方法来执行所有计算，如下所示：

private void calculatePrice() {
        String strItem = spnSelectItem.getSelectedItem().toString();
        String qty = spnQty.getSelectedItem().toString();
        String discount = spnItemDiscount.getSelectedItem().toString().replace("%", "");
        //perform calculate and update UI as you like
    }

然后要么为所有三个微调器创建一个侦听器，要么在所有微调器中调用它们，例如：

spnSelectItem.setOnItemSelectedListener(new OnItemSelectedListener() {
        @Override
        public void onItemSelected(AdapterView<?> arg0, View arg1,
                int arg2, long arg3) {
            //do some work, update UI or reset qty and discount spinner or whatever
            strItem = spnSelectItem.getItemAtPosition(arg2).toString();
            //call calulcate method
            calculatePrice();
        }
    });