I think this is a question for experts.
I get calls to getView() with positon out of bounds from the ListView data list.
This happens when I use the Adapter filter. The filter publishResults() method populates the data with a filtered list which is smaller than the original list.
The error seems to occur when the new filtered list is shorter than the previous filtered list.
I changed the code of getView() to return a dummy convertView when out of bounds, just to see how many such calls are issued.
These are the relevant code and the log messages I logged:
@Override
public View getView(int position, View convertView, ViewGroup parent) {
// No logs here to keep ListView performance good
Log.d(TAG, "+ getView( position=" + position + ")");
ViewHolder holder;
if( position >= mData.size() ) {
// This code allows to see how many bad calls I get
Log.w(TAG, "position out of bounds!");
convertView = mInflater.inflate(mLayout, parent, false);
return convertView;
}
. . . // Normal getView code
return convertView;
}
In the filter (code copied as is from ArrayAdapter source code)
@Override
protected void publishResults(CharSequence constraint, FilterResults results) {
Log.pe(TAG, "+ publishResults(constraint:" + constraint + ", results.count:" + results.count + ")");
//noinspection unchecked
mData = (ArrayList<String>) results.values;
if (results.count > 0) {
notifyDataSetChanged();
} else {
notifyDataSetInvalidated();
}
Log.px(TAG, "- publishResults()");
}
The log file shows that after a filter with 7 results, comes a fitler with 3 results, but getView keeps getting calls for 7 items (I marked with *** the out of bounds calls):
02-26 05:31:55.986: D/ViewerActivity(22857): + onQueryTextChange(newText:log)
02-26 05:31:55.986: D/ViewerActivity(22857): - onQueryTextChange()
02-26 05:31:56.029: D/LogScreenAdapter(22857): + performFiltering(prefix:log)
02-26 05:31:56.113: D/dalvikvm(22857): GC_CONCURRENT freed 378K, 5% free 13577K/14215K, paused 0ms+1ms
02-26 05:31:56.153: D/LogScreenAdapter(22857): - performFiltering()
02-26 05:31:56.153: D/LogScreenAdapter(22857): + publishResults(constraint:log, results.count:7)
02-26 05:31:56.167: D/LogScreenAdapter(22857): - publishResults()
02-26 05:31:56.167: D/LogScreenAdapter(22857): + getView( position=0)
02-26 05:31:56.167: D/LogScreenAdapter(22857): + getView( position=0)
02-26 05:31:56.167: D/LogScreenAdapter(22857): + getView( position=0)
02-26 05:31:56.167: D/LogScreenAdapter(22857): + getView( position=1)
02-26 05:31:56.167: D/LogScreenAdapter(22857): + getView( position=2)
02-26 05:31:56.167: D/LogScreenAdapter(22857): + getView( position=3)
02-26 05:31:56.167: D/LogScreenAdapter(22857): + getView( position=4)
02-26 05:31:56.167: D/LogScreenAdapter(22857): + getView( position=5)
02-26 05:31:56.167: D/LogScreenAdapter(22857): + getView( position=6)
02-26 05:31:56.167: D/LogScreenAdapter(22857): + getView( position=0)
02-26 05:31:56.167: D/LogScreenAdapter(22857): + getView( position=1)
02-26 05:31:56.167: D/LogScreenAdapter(22857): + getView( position=2)
02-26 05:31:56.167: D/LogScreenAdapter(22857): + getView( position=3)
02-26 05:31:56.167: D/LogScreenAdapter(22857): + getView( position=4)
02-26 05:31:56.493: D/LogScreenAdapter(22857): + getView( position=5)
02-26 05:31:56.503: D/LogScreenAdapter(22857): + getView( position=6)
02-26 05:32:23.793: D/ViewerActivity(22857): + onQueryTextChange(newText:logs)
02-26 05:32:23.793: D/ViewerActivity(22857): - onQueryTextChange()
02-26 05:32:23.813: D/LogScreenAdapter(22857): + performFiltering(prefix:logs)
02-26 05:32:23.854: D/dalvikvm(22857): GC_CONCURRENT freed 383K, 5% free 13577K/14215K, paused 0ms+0ms
02-26 05:32:23.924: D/dalvikvm(22857): GC_CONCURRENT freed 388K, 5% free 13573K/14215K, paused 0ms+1ms
02-26 05:32:23.974: D/LogScreenAdapter(22857): - performFiltering()
02-26 05:32:23.983: D/LogScreenAdapter(22857): + publishResults(constraint:logs, results.count:3)
02-26 05:32:23.983: D/LogScreenAdapter(22857): - publishResults()
02-26 05:32:23.983: D/LogScreenAdapter(22857): + getView( position=0)
02-26 05:32:24.074: D/LogScreenAdapter(22857): + getView( position=0)
02-26 05:32:24.093: D/LogScreenAdapter(22857): + getView( position=0)
02-26 05:32:24.113: D/LogScreenAdapter(22857): + getView( position=1)
02-26 05:32:24.155: D/LogScreenAdapter(22857): + getView( position=2)
02-26 05:32:24.164: D/LogScreenAdapter(22857): + getView( position=3)
*** 02-26 05:32:24.193: W/LogScreenAdapter(22857): position out of bounds!
02-26 05:32:24.233: D/LogScreenAdapter(22857): + getView( position=4)
*** 02-26 05:32:24.263: W/LogScreenAdapter(22857): position out of bounds!
02-26 05:32:24.284: D/LogScreenAdapter(22857): + getView( position=5)
*** 02-26 05:32:24.313: W/LogScreenAdapter(22857): position out of bounds!
02-26 05:32:24.333: D/LogScreenAdapter(22857): + getView( position=6)
*** 02-26 05:32:24.343: W/LogScreenAdapter(22857): position out of bounds!
02-26 05:32:24.353: D/LogScreenAdapter(22857): + getView( position=0)
02-26 05:32:24.373: D/LogScreenAdapter(22857): + getView( position=1)
02-26 05:32:24.383: D/LogScreenAdapter(22857): + getView( position=2)
02-26 05:32:24.403: D/LogScreenAdapter(22857): + getView( position=3)
*** 02-26 05:32:24.413: W/LogScreenAdapter(22857): position out of bounds!
02-26 05:32:24.433: D/LogScreenAdapter(22857): + getView( position=4)
*** 02-26 05:32:24.443: W/LogScreenAdapter(22857): position out of bounds!
02-26 05:32:24.463: D/LogScreenAdapter(22857): + getView( position=5)
*** 02-26 05:32:24.475: W/LogScreenAdapter(22857): position out of bounds!
02-26 05:32:24.483: D/LogScreenAdapter(22857): + getView( position=6)
*** 02-26 05:32:24.503: W/LogScreenAdapter(22857): position out of bounds!
02-26 05:38:26.769: D/dalvikvm(22857): GC_CONCURRENT freed 316K, 5% free 13640K/14215K, paused 0ms+1ms
What you are seeing here, the publishResults() method did change mData from a list of 7 items to a shorter list of 3 items, see the code above, but the Adapter keeps getting getView() calls for the 7 items list, even that it is not longer there.
Note that notifyDataSetChanged() has been called with the new data assignment, so the ListView should be aware of the new list.