Android - Custom ListView Viewholder

Question

I am trying to display detailed Product information in an custom Listview with two TextViews per row for the key/value pair. The data is displayed correct. I also colored every second line different.

And there is my Problem. If I scroll up and down the different colored rows change their color and remain in this state. The data is not affected from this problem. Just the backroundcolor of the TextViews. I use the ViewHolder Pattern but this did not change anything. I added the code of the adapter. I think thats enough. Have you any idea?

Screenshot of the problem:

Code:

public class ProductDetailAdapter extends BaseAdapter {

private LinkedHashMap<String,String> list;
private Context context;

public ProductDetailAdapter(Context c, LinkedHashMap<String,String> list){
    super();
    this.context = c;
    this.list=list;

}
@Override
public int getCount() {
    return list.size();
}

@Override
public Object getItem(int position) {
    return list.get(position);
}

@Override
public long getItemId(int position) {
    return position;
}

@Override
public View getView(int position, View convertView, ViewGroup viewGroup) {

    LayoutInflater inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);

    ProductDetailAdapter.ViewHolder viewHolder;

    if(convertView == null){
        convertView=inflater.inflate(R.layout.product_detail_data_row,null);
        viewHolder = new ViewHolder();
        viewHolder.textViewKey = (TextView) convertView.findViewById(R.id.productDataKey);
        viewHolder.textViewValue = (TextView) convertView.findViewById(R.id.productDataValue);
        convertView.setTag(viewHolder);

    }else {
        viewHolder = (ProductDetailAdapter.ViewHolder) convertView.getTag();
    }

    viewHolder.textViewKey.setText((String)list.keySet().toArray()[position]);
    viewHolder.textViewValue.setText(list.get(list.keySet().toArray()[position]));

    if(position % 2 == 0){
        viewHolder.textViewKey.setBackgroundColor(context.getResources().getColor(R.color.colorParkerWhite2));
        viewHolder.textViewValue.setBackgroundColor(context.getResources().getColor(R.color.colorParkerWhite2));
    }

    return convertView;
}

private static class ViewHolder {

    public TextView textViewKey;
    public TextView textViewValue;

    public ViewHolder(){};

}
}

image url: https://i.stack.imgur.com/OS3Op.png works fine for me — Mike, Mar 02 '17 at 13:57
Try creating new `ViewHolder instance` inside `if(position % 2 == 0)` — aldakur, Mar 02 '17 at 14:00

score 4 · Accepted Answer · answered Mar 02 '17 at 13:59

That happens because the rows are being recycled. It's a common problem.

You can solve it by doing:

if(position % 2 == 0){
    viewHolder.textViewKey.setBackgroundColor(context.getResources().getColor(R.color.colorParkerWhite2));
    viewHolder.textViewValue.setBackgroundColor(context.getResources().getColor(R.color.colorParkerWhite2));
} else {
    viewHolder.textViewKey.setBackgroundColor(context.getResources().getColor(R.color.colorParkerWhite1)); //Or the color that you want for odd rows
    viewHolder.textViewValue.setBackgroundColor(context.getResources().getColor(R.color.colorParkerWhite1)); //Or the color that you want for odd rows
}

score 0 · Answer 2 · edited Jun 20 '20 at 09:12

0

Try this:

super( c, 0, list );

instead of this:

super();

Once you pass the data source to the adapter you no longer need :

getCount

getItem

getItemId

edited Jun 20 '20 at 09:12

Community

1
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answered Mar 02 '17 at 14:08

RonTLV

2,376
2
24
38

score 0 · Answer 3 · edited May 23 '17 at 11:46

0

please refer this link and link2 and link3 these will work for you

edited May 23 '17 at 11:46

Community

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answered Mar 02 '17 at 14:08

vijay chhalotre

396
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11

Android - Custom ListView Viewholder

3 Answers3