Android : Poor performance with Android ListView

In our Android application we've got a ListView filled with active chatsessions between different users. There's no real limit to how many active chatsessions a user can have, so obviously there's no limit to how many items this ListView contains either.

Each ListView item consists of:

• 1x inflated View holding several images


• 1x ImageView


• 1x String

Everything works out the way we want to in terms of loading times and in terms of looks and composition. While the ListView contains below 20-ish items, everything is ok. As soon as the ListView starts containing above those 20-ish items, the performance turns gradually more and more unbearable for each item added.

I've been doing some trial and error testing, trying to disable each element and component of the item structure, and what I've found is that the performance drop happens whenever we have any kind of image in the items. So no matter what kind, any image causes the performance to suck, when the ListView contains more than 20-ish items. How do I optimize this? I've attached the getView from our adapter + our method for adding the photos.

Any and all help and/or suggestions are appreciated :)

getView from our adapter:

public View getView(int position, View convertView, ViewGroup parent) {
    System.out.println("getview:"+position+" "+convertView);

    ViewHolder viewHolder;

    Match match = matches.get(position);

    if(convertView==null){
        LayoutInflater inflater = (LayoutInflater) mContext
                .getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        convertView = inflater.inflate(R.layout.matches_list_item,  parent, false);

        viewHolder = initViewHolder(convertView, match);

    } else {

        viewHolder = (ViewHolder) convertView.getTag();
    }

    addGroupPhoto(imageSize, match, viewHolder, false);

    if (match.matchedGroup != null) {

        viewHolder.names.setText(match.matchedGroup.getMembersNames());
        viewHolder.matchedText.setText(match.latestMessage.value == null ?
                String.format(mContext.getString(R.string.matched_on), getFormatedMatchDate(match.matchedOn)) : match.latestMessage.value);

    }
    return convertView;
}

addGroupPhoto from our adapter

private void addGroupPhoto(int imageSize, Match match, ViewHolder viewHolder,     boolean isSelected) {

    if (viewHolder.groupPhoto.findViewById(R.id.unseen_messages) != null) {
        viewHolder.groupPhoto.removeView(viewHolder.groupPhoto.findViewById(R.id.unseen_messages));
    }

    if (match.matchedGroup != null) {
        RelativeLayout lay = Utilities.createGroupImagePhoto(mContext, imageSize, imageSize, match.matchedGroup.members, Utilities.GROUP_PHOTO_MODE_GROUP_WITHOUT_NAMES);
        ((RelativeLayout.LayoutParams)lay.getLayoutParams()).addRule(RelativeLayout.CENTER_VERTICAL);
        ((RelativeLayout.LayoutParams)lay.getLayoutParams()).addRule(RelativeLayout.ALIGN_LEFT);
        ((RelativeLayout.LayoutParams)lay.getLayoutParams()).setMargins(smallMargin, 0, 0, 0);
        viewHolder.groupPhoto.addView(lay);
        lay.invalidate();
    }

    ImageView crop = new ImageView(mContext);
    crop.setBackgroundResource(getCropImageDrawable(isSelected));
    crop.setLayoutParams(new RelativeLayout.LayoutParams(imageSize,imageSize));
    ((RelativeLayout.LayoutParams)crop.getLayoutParams()).addRule(RelativeLayout.CENTER_VERTICAL);
    ((RelativeLayout.LayoutParams)crop.getLayoutParams()).addRule(RelativeLayout.ALIGN_LEFT);
    ((RelativeLayout.LayoutParams)crop.getLayoutParams()).setMargins(smallMargin, 0, 0, 0);

    int marginForMessage = 0;

    viewHolder.groupPhoto.addView(crop);
    if (!match.seen | match.newMessages > 0) {
        addMessages(match.newMessages,  marginForMessage, viewHolder);
    }
}