Images are repeating in ListView

Question

I have implemented android app which should download images from server and display them in ListView, but very interesting thing occures while images are downloading

Answer 1

Views are reused for performance with Adapters. You should use another approch . You have to have a class holder which reuse your views. In your case you class should be something like this:

   public class MoviesAdapter extends ArrayAdapter {
    private ArrayList movieDataItems;   
    private Activity context;

    public MoviesAdapter(Activity context, int textViewResourceId,       ArrayList movieDataItems) {
        super(context, textViewResourceId, movieDataItems);
        this.context = context;
        this.movieDataItems = movieDataItems;
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) { 
        if (convertView == null) {
            LayoutInflater vi = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            convertView = vi.inflate(R.layout.movie_data_row, null);

                holder = new ViewHolder();

                holder.imageView = (BarImageView) convertView.findViewById(R.id.movie_thumb_icon);
              } else {
                        holder = (ViewHolder) convertView.getTag();

                  }

        ParkCinema movie = movieDataItems.get(position);

        if (movie!=null){

                    String url = movie.poster();

                     if (url!=null) {
                        Bitmap bitmap = fetchBitmapFromCache(url);
                        if (bitmap==null) { 
                            new BitmapDownloaderTask(imageView).execute(url);
                        }
                        else {
                            imageView.setImageBitmap(bitmap);
                        } 
                    } 
        }
        return convertView;
    }

    private LinkedHashMap bitmapCache = new LinkedHashMap();

    private void addBitmapToCache(String url, Bitmap bitmap) {
        if (bitmap != null) {
            synchronized (bitmapCache) {
                bitmapCache.put(url, bitmap);
            }
        }
    }

    private Bitmap fetchBitmapFromCache(String url) {

        synchronized (bitmapCache) {
            final Bitmap bitmap = bitmapCache.get(url);
             if (bitmap != null) {
                return bitmap;
            } 
        }

        return null;


public static class ViewHolder {


        ImageView imageView; 


    }

    }