ListView Position Issue in getView(...)

Question

I have three Items in a ListView, and on each and every list item i have three TextView(s), one contains item price, second to show Quantity and third to show Total of that item.

Also two more TextView(s), one to increase the quantity and second to decrease the quantity.

Now the issue is whenever i make changes in quantity of first or second list item, it effects on quantity and total amount of third list item (i.e - Last item in a List)

public class CartAdapter extends BaseAdapter {


ViewHolder holder;  

......

@Override
    public View getView(final int position, View convertView, ViewGroup parent) {
        // convert view = design

        View v = convertView;
        if (v == null) {
            holder = new ViewHolder();
            v = layoutInflater.inflate(Resource, null);

            holder.textViewPrice = (TextView) v.findViewById(R.id.textPrice);
            holder.editTextQuantity = (EditText) v.findViewById(R.id.editQuantity);
            holder.textViewTotal = (TextView) v.findViewById(R.id.textTotal);                   

            v.setTag(holder);           

        } else {

            holder = (ViewHolder) v.getTag();

        }

        holder.textViewPrice.setText("$ " +cartArrayList.get(Integer.parseInt(holder.textViewPrice.getTag())).getPrice());

        cart = cartArrayList.get(Integer.parseInt(v.getTag()));

               holder.editTextQuantity.setText(String.valueOf(cart.getQuantity()));     

        df = new DecimalFormat("0.00##");

        totalPrice = cart.getQuantity() * cart.getPrice();   
        cart.setTotal(totalPrice);
        holder.textViewTotal.setText("$ " + df.format(cart.getTotal()));

return v;

}

where is the code which executes on changing quantity edit text? — Asif Mujteba, May 07 '15 at 06:18
is Your viewHolder global? I can´t see where You set ViewHolder holder; — Opiatefuchs, May 07 '15 at 06:29
Initialize your ViewHolder object at start of getView method. — Jitesh Dalsaniya, May 07 '15 at 06:45
@JiteshDalsaniya thank you so much i tried your way and trick worked for me.... and i also removed v.setTag(holder); } else { holder = (ViewHolder) v.getTag(); } post it as your answer — Sun, May 07 '15 at 06:55
can you also try overriding `getItem(int position)` and `getItemId(int position)` .Do these changed values only reflect on ui or also in your arraylist? — Droidekas, May 07 '15 at 06:55

score 1 · Accepted Answer · answered May 07 '15 at 07:05

1

Initialize your ViewHolder object at start of getView method.

answered May 07 '15 at 07:05

Jitesh Dalsaniya

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score 0 · Answer 2 · answered May 07 '15 at 06:24

try this way

  @Override
        public View getView(final int position, View convertView, ViewGroup parent) {
            // convert view = design

            View v = convertView;
            if (v == null) {
                holder = new ViewHolder();
                v = layoutInflater.inflate(Resource, null);

                holder.textViewPrice = (TextView) v.findViewById(R.id.textPrice);
                holder.editTextQuantity = (EditText) v.findViewById(R.id.editQuantity);
                holder.textViewTotal = (TextView) v.findViewById(R.id.textTotal);                   

                v.setTag(holder);           

            } else {

                holder = (ViewHolder) v.getTag();

            }
            v.setTag("ID",position);
            holder.textViewPrice.setTag(position);
            holder.editTextQuantity.setTag(position);
            holder.textViewTotal.setTag(position);
            holder.textViewPrice.setText("$ " +cartArrayList.get(Integer.parseInt(holder.textViewPrice.getTag())).getPrice());

            cart = cartArrayList.get(Integer.parseInt(v.getTag()));

                   holder.editTextQuantity.setText(String.valueOf(cart.getQuantity()));     

            df = new DecimalFormat("0.00##");

            totalPrice = cart.getQuantity() * cart.getPrice();   
            cart.setTotal(totalPrice);
            holder.textViewTotal.setText("$ " + df.format(cart.getTotal()));

    return v;

}

i have posted updated code, but still facing same issue – Sun May 07 '15 at 06:43 — Sun, May 07 '15 at 06:43

score 0 · Answer 3 · answered May 07 '15 at 06:59

There is only one holder variable in your base adapter. It's getting updated with each call to getView(). THe problem is that your click listeners are using that holder variable to update the views. SInce the holder is now pointing to the last view item that was created, that's the one that's getting updated in the onClick.

A simple way to solve the problem is to create a final ViewHolder variable and use it in the onClicks. You can use the same variable for both OnClickListeners.

like so..

final ViewHolder perItemHolder = holder;
holder.textQtyIncrease.setOnClickListener(new OnClickListener() {

    @Override
    public void onClick(View v) {
        // TODO Auto-generated method stub

        if(p == 9) {
            Toast.makeText(context, "You have reached to maximum order quantity", Toast.LENGTH_LONG).show();
            return ;
        }
        else {
            p = p+1;
            perItemHolder.textViewQuantity.setText(""+p);

            totalPrice = p * cart.getPrice();    
            cart.setTotal(totalPrice);
            perItemHolder.textViewTotal.setText("$ " + df.format(cart.getTotal()));
        }
    }
});

ListView Position Issue in getView(...)

3 Answers3