Image shuffles in list view. when scrolling

Question

What happens is that when scrolling the list, the images that were loaded on each item are shuffled, and the avatar of each item going to the next item ends. I do not know if I\

Answer 1

import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.ImageView;
import android.widget.TextView;

import java.util.ArrayList;

public class CustomListAdapter extends BaseAdapter {
    private ArrayList listData;
    private LayoutInflater layoutInflater;

    public CustomListAdapter(Context context, ArrayList listData) {
        this.listData = listData;
        layoutInflater = LayoutInflater.from(context);
    }

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

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

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

    public View getView(int position, View convertView, ViewGroup parent) {
        ViewHolder holder;
        if (convertView == null) {
            convertView = layoutInflater.inflate(R.layout.list_row_layout, null);
            holder = new ViewHolder();
            holder.headlineView = (TextView) convertView.findViewById(R.id.title);
            holder.reporterNameView = (TextView) convertView.findViewById(R.id.reporter);
            holder.reportedDateView = (TextView) convertView.findViewById(R.id.date);
            holder.imageView = (ImageView) convertView.findViewById(R.id.thumbImage);
            convertView.setTag(holder);
        } else {
            holder = (ViewHolder) convertView.getTag();
        }

        NewsItem newsItem = (NewsItem) listData.get(position);
        holder.headlineView.setText(newsItem.getHeadline());
        holder.reporterNameView.setText("By, " + newsItem.getReporterName());
        holder.reportedDateView.setText(newsItem.getDate());

        Drawable placeholder = holder.imageView.getContext().getResources().getDrawable(R.drawable.placeholder;
                holder.imageView.setImageDrawable(placeholder);       

            new ImageDownloaderTask(holder.imageView).execute(newsItem.getUrl());

        return convertView;
    }

    static class ViewHolder {
        TextView headlineView;
        TextView reporterNameView;
        TextView reportedDateView;
        ImageView imageView;
    }