How to handle Number Format Exception in edittext OntextChanged

Question

I have edit text in my app to manipulate product quantity, but the issue if I will change the quantity , on that time getting NPE. to change the quantity in edit text I need to remove existing and need to add a new one, please check following code

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

When you remove everything on your editText, editText will return an empty string. Hence you will get NPE and also Number Format Exception.

You can handle like this:

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());
}

To compare initial value with current value

First you need to assign a variable as initial value in beforeTextChanged.

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

Then in onTextChanged:

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
}

Have a look on this https://stackoverflow.com/a/20278708/5156075