Image Reloaded When Scroll ListView In Android

I am trying write a news list application. I had parsed JSON data from Server and created CustomListAdapter. There are three textView and imageView in my listView. It works great,

Solution 1:

Try Below code, It might help you to resolve your problem.

public class ListViewCustomAdapter extends..{

   //Map to cache Image Bitmap. Key= imageUrl,value =Image Bitmap
   private Map<String, Bitmap> mBitmapCache = new HashMap<String, Bitmap>();    

   @Override
   public View getView(int position, View convertView, ViewGroup parent) {
      ViewHolder holder;

      if (convertView == null) {
          convertView = inflater.inflate(R.layout.row, null);
          holder = new ViewHolder();
          holder.nTitle = (TextView) convertView.findViewById(R.id.listTitle);
          holder.nDate = (TextView) convertView.findViewById(R.id.listDate);
          holder.nCategory = (TextView) convertView.findViewById(R.id.listCategory);
          holder.nImage = (ImageView) convertView.findViewById(R.id.listImage);
          convertView.setTag(holder);
      } else {
          holder = (ViewHolder) convertView.getTag();
      } 

      if (newsList.get(position) != null) {
          holder.imageUrl = newsList.get(position).image;
          holder.nTitle.setText(newsList.get(position).title);
          holder.nCategory.setText(newsList.get(position).category);
          holder.nDate.setText(Base.getInstance(context).getDateString(newsList.get(position).date));
          if (holder.imageUrl != null && !holder.imageUrl.equals("null")) {
               String thumbUrl = holder.imageUrl.substring(0, holder.imageUrl.lastIndexOf('.')) + "-260x145" + holder.imageUrl.substring(holder.imageUrl.lastIndexOf('.'), holder.imageUrl.length());
               holder.setImage(thumbUrl);
          }
      }
      return convertView;
   }

   private static class ViewHolder {
        TextView nTitle;
        TextView nDate;
        TextView nCategory;
        ImageView nImage;
        String imageUrl;

        public void setImage(String imageUrl) {
           this.imageUrl = imageUrl;
           Bitmap imageBitmap = mBitmapCache.get(imageUrl);
           if(imageBitmap!=null){
               nImage.setImageBitmap(imageBitmap);
           } else {
               AsyncHttpClient client = new AsyncHttpClient();
               client.get(imageUrl, null, fileHandler);
           }
        }

        FileAsyncHttpResponseHandler fileHandler = new FileAsyncHttpResponseHandler(context) {
             @Override
             public void onFailure(int statusCode, Header[] headers, Throwable throwable,
                      File response) {
             }

             @Override
             public void onSuccess(int statusCode, Header[] headers, File response) {
                   Bitmap imageBitmap = BitmapFactory.decodeFile(response.getPath());
                   imageView.setImageBitmap(imageBitmap);
                   mBitmapCache.put(imageUrl, imageBitmap);         
             }
        };
    }
}

Solution 2:

Your code in

public void setImage() {
    if (imageUrl != null && !imageUrl.equals("null") && !imageUrl.equals("")) {
        AsyncHttpClient client = new AsyncHttpClient();
        client.get(imageUrl, null, fileHandler);
    }
}

looks suspicious: any valid URL will force a reloading as it matches all three conditions in

    imageUrl != null && !imageUrl.equals("null") && !imageUrl.equals("")

Example: http://www.google.com/logo.png is not null, does not equal the string "null" nor the string "", so the if will always be true and the AsyncLoader created. BTW, checking for "null" only makes sense if you are explicitly using that somewhere else in your code. Most probably you only want to check for the null value, not the "null" string.