Lots of GC when scrolling ListView (with holder pattern)

Question

It's a similar question to this, but the solution doesn't work. The problem is that the scrolling of `ListView` is very sluggish which is because of lots and lots of GCs. I use holder pattern (view caching) as you can see in the code below: ``` public View getView(int position, View convertView, ViewGroup parent) { ViewHolder holder; if (convertView == null) { convertView = mInflater.inflate(R.layout.eventrow, parent, false); holder = new ViewHolder(); holder.title = (TextView) convertView.findViewById(R.id.eventTitle); holder.place = (TextView) convertView.findViewById(R.id.eventPlace); convertView.setTag(holder); } else { // Get the ViewHolder back to get fast access to the TextView // and the ImageView. holder = (ViewHolder) convertView.getTag(); } // Bind the data efficiently with the holder. holder.title.setText(((EventItem) getItem(position)).getTitle()); holder.place.setText(((EventItem) getItem(position)).getPlace_name()); return convertView; } ``` I removed `cacheColorHint` a…

Accepted Answer

```
android:scrollingCache="false"
```

Is the solution.

The docs say:

When set to true, the list uses a drawing cache during scrolling. This makes the rendering faster but uses more memory.

Now this does not give us any hint about the implementation details. I have an idea without investing hours of code analyzes. For caching purposes, like Google recommends in their own documents, they use WeakReferences or WeakHashMaps. But it looks like the Dalvik VM is a bit too eager to kill off these References and causes them to be rebuild every time. This explains the huge GC activity and the sluggish user experience.

Links: Blog about useless WeakReferences due to bug: http://chriswstewart.com/post/14199645893/improving-the-android-listview Dalvik VM bug discussion: https://groups.google.com/forum/#!topic/android-developers/66uw2t84rME

Lots of GC when scrolling ListView (with holder pattern)

Solution

Problem

Related problems